Home

Technical Manual

Contents

1. Cloud Particle Imager CPI V2 5 User s Manual SPEC Inc 3022 Sterling Circle Suite 200 Boulder CO 80301 February 2013 TABLE OF CONTENTS Section lt CPIOVERV IEW ssc iice cern ice ceccecocesscisccadace acca seceecosssoaas aa aasiu ca saa avesven ss cansesancoccoseecassouseeeusasenseuss 1 1 1 CPI General Description 1 1 1 Main Parts of The CPI 1 1 2 Functional Overview 1 1 2 1 Instrument Behavior With No Particle Present 1 1 2 2 Instrument Behavior With Particle s Present Section 2 GETTING STARTED ciccara 7 2 1 Unpacking the CPI System 2 2 Connecting the CPI Sensor Head to the Data Acquisition System 2 2 1 Connection Procedure for Operating the CPI in the Laboratory 2 2 2 Connection Procedure for Installing the CPI on an Airplane 2 3 CPI Atomizer Setup for Laboratory Testing 2 4 CPI Startup Procedure 2 5 Disconnecting the CPI Cables 2 6 Packing CPI System Section 3 PHYSICAL DESCRIPTION acrocar inna aaa a 29 3 1 CPI Sensor Head Physical Description Sectiona THEORY OF OPERATION conscendere 36 4 1 Optical System Description 4 1 1 PDS System 4 1 2 Imaging System 4 1 3 Physical Location of Optical Components 4 2 Detailed Description of Electronics 4 2 1 Particle Detection System PDS 4 2 2 1 Logical State Machine 4 2 2 PDS Logic and Camera Image Processing 4 2 2 1 Logical State Machine 4 2 3 PDS 45 PDS 90 amp Imaging Laser Drivers 4 2 4 DSP Data Acquisition and Control 4 2 5 Power Supply Board Section
2. 13 Mate the camera data connector Figure 6 4 12 14 Verify all cables have been mated and are strain relieved to the table Figure 6 4 13 15 The internal sensor is now ready to be operated in the laboratory 16 To remove the internal sensor from the test stand verify that sensor and computer power are off and follow the above procedure in reverse SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice LOZ SPEC CPI Preliminary Technical Manual CPI INTERNAL SENSOR TEST STAND UNIVERSAL JOINT SCREW MMMM USE CAUTION AROUND THESE ee SAFE SURFACE a COMPONENTS WHEN HANDLING e INTERNAL SENSOR Figure 6 4 1 Figure 6 4 2 TEST STAND MOUNTING SCREWS TEST STAND MOUNTING PLATE INTERNAL SENSOR MOUNTING POINTS NA ALIGN SENSOR WITH MOUNT PLATE i Figure 6 4 3 Figure 6 4 4 a i z GET SCREW STARTED ON THIS SIDE AND GRADUALLY TIGHTEN BOTH SCREWS Figure 6 4 5 SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice Ree SPEC CPI Preliminary Technical Manual Figure 6 4 6 _ Figure 6 4 7 fi Figure 6 4 10 Figure 6 4 11 SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 134 SPEC CPI Preliminary Techn
3. SAMPLE VOLUME INLET ADAPTER Figure 3 1 2 Cutaway view of CPI Sample Tube showing relevant components SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 30 SPEC CPI Preliminary Technical Manual NOSE CONE BLON FORWARD SAMPLE AFT SAMPLE CENTRAL OPTICAL TUBE SAMPLE TUBE TUBE NOT SHOWN BLOCK i f V x y Y _ e a J m 4 E g p az l bi f 1 OG sa tt b f me INLET ADAPTER Figure 3 1 3 Photograph showing the physical location of the various sample tube components Figure 3 1 4 is a cutaway view of the optical block showing the locations of the three laser beam paths through the sample volume The location of the six windows is also shown Knowledge of the window locations is important for cleaning of the windows Contamination on the PDS output windows has the largest effect on the PDS DC detector levels During cleaning the real time software should be running to provide feedback for the cleaning process If the PDS DC level increases after a particular PDS window is cleaned that window needs to be cleaned again Removal of contamination from the windows should result in a decrease in the baseline stray light hitting the PDS detectors SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice Sal SPEC CPI Preliminary
4. Use the CPI pulling fork to begin sliding the aft sample tube into the internal sensor Push the fork and the internal sensor in the direction shown in Figure 6 5 12 If necessary pull up slightly on the green handle to help the aft tube clear the mount base as is slides forward The internal sensor will be in its final forward position when the pylon spreader and internal sensor are fully mated Figure 6 5 13 Continue pushing the aft sample tube into the internal sensor with the fork until the holes in the mount base align with the aft sample tube holes Figure 6 5 14 Install the 2X 8 32 torx plus fasteners and tighten with the T15 torx plus driver Figure 6 5 15 Check that both fasteners have been completely tightened Figure 6 5 16 Figure 6 5 17 shows the first set of connectors to be mated Using a small flat blade screws driver fasten connectors J20S and J21S as shown in Figure 6 5 18 Use a 3 32 ball driver or hex wrench to fasten the mounting screws for connector J22S Mate camera connector and J23S as shown in Figure 6 5 19 Verify all connectors have been mated and tightened Figure 6 5 20 SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice L3G SPEC CPI Preliminary Technical Manual 24 Before proceeding to install the pylon cover operate the CPI in the pylon to verify no problems occurred during the internal sensor
5. 3 Valid Frames Frames Captured Frames Attempted x 100 4 Imaged Particles The number of ROIs cut out from searched image frames 5 Particle Concentration An estimate of the number of particles per liter based on the air speed RO Concentration TBD 6 PDS Strobes Total number of transit time qualified particles sensed 7 Laser Strobes The number of times the imaging laser was fired in an attempt to image a sensed particle 8 Image Mean The mean of the last processed frame 9 Transit Time Interval during which the particle was in both PDS beams SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 88 SPEC CPI Preliminary Technical Manual 10 Missed PDS TBD 11 Imaged Particles The number of ROIs found in the last processed frame 5 1 6 2 Displays Histograms and ROI X Y Plots The last tab available in the Settings Window is the Disp Hist tab shown in Figure 5 1 15 Under the label Layout the number of columns and rows for displaying particle images is selected Shown in Figure 5 1 15 is Cols 5 and Rows 4 This corresponds to the number of available ROI display boxes in the Image Display section of Figure 5 1 1 Each box will display a single ROI when particles are successfully imaged When changing the number of columns and rows the size of the ROI display boxes is changed in the DX and DY fields correspon
6. 90 PDS INPUT PDS MIRROR CYLINDRICAL LENS wannow SAMPLE PDS MASK CLYINDRICAL go 90 PDS COLLECTION 90 PDS LENS COLLIMATING N BARREL _ 90 PDS BEAM PATH MIRROR RELAY 1 90 PDS DUMP SPOT COLLECTION RELAY 2 WINDOW 90 APD FOCUSING LENS 90 PDS DETECTOR Figure 4 1 1 90 PDS system optical component layout SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 3T SPEC CPI Preliminary Technical Manual PDS DDS PDS COLLIMATING CYLINDRICAL CYLINDRICAL NARROW LASER LENS LENS1 LENS2 MASK I a ma 2mm 5mm LASER ODI ASPHERIC AGOA PERNE aE VEHE CYLINDRICAL CYLINDRICAL RECTANGULAR ey m LENS APERTURE 50mW F 11 mm Tea E APERTURI 2 5 mm X 1 mm b X BEAM BEAM CROSS SECTION 1 CROSS SECTION 2 Figure 4 2 2 Ray trace for PDS laser beam shaping optics with a view of compressed axis and b view of uncompressed axis The lasers used for the PDS system are Hitachi HL7851 laser diodes The lasers operate at a wavelength of 785 nm with a maximum output power of 40 mW The output from the laser diode has an elliptically divergent beam with a parallel divergence angle of 9 5 and a perpendicular divergence angle of 23 An aspheric lens is used to produce a collimated beam with an elliptical cross section As shown in Figure 4 2 2 the dimensions of the collimated beam are approximately 5 5
7. from the CCD camera The EXSYNC signal is generated by the frame grabber card in the data system computer and goes to two places the Basler A501 CCD camera and the DSP board If the state machine did not have to wait for the EXSYNC pulse from the frame grabber in S3 or the CLEAR HOLD signal from the DSP in S4 it could run through its eight step cycle many thousands of times in the time between EXSYNC pulses which is the same time that it takes the camera to download one image to the data acquisition system Forcing it to wait in S3 for EXSYNC from the frame grabber and to wait in S4 for CLEAR HOLD from the DSP slows it down and synchronizes it somewhat with the entire image capturing process When the state machine receives a CLEAR HOLD signal from the DSP it advances from S4 to S5 It immediately moves from S5 to S6 In S6 it puts out a CLR_SMPL signal This signal discharges the peak hold capacitors in the PDS 45 pulse peak detector U19 and the PDS 90 pulse peak detector U27 see Block Diagram in Figure 4 2 1 and schematic diagrams in Appendix 7 1 The state machine immediately moves from S6 to S7 In S7 it continues to put out a CLR_SMPL signal If no particles are detected in the PDS laser beams it will go to S0 otherwise it will wait here In SO it idles and waits for the next particle When the PDS detectors see the next particle the cycle repeats itself EXSYNC causes the CCD camera to download its current image to the data system com
8. Data File D 02161240 roi RECORDING DISABLED Time 2 16 12 41 2 Fie View Settings Commands Window Help Live STOP Record TAKE A PROBE hci T Data BKGROUND Pelee ON T Display SETTINGS cer ans t FF z Statistics y xj Disabled Qual 4 E E Sme Particle amp Other Rates Interval sec Statis INQOW pe TT N Frms Captured 0 0 Fims Attempted 0 0 w Pt 0 0 12206223201 S r A J Evae o 1 imaged Particles 0 0 ial ROL Location a Paice cone toe 713 479 39 736 ae ROI Locations es ROI Conc 1 L 0 PE m ctome ae O PDS Strobes 00 a EEEE vg Dead Time O Last Frame Img Mean 131 Bkg Mean 131 B ackgrounds fi Ready a PROBE ACQUIRING NUM A Start i ue Data File D 0216124 __fJuntitled Paint CLJ 12 41 PM Figure 2 4 5 Startup screen of CPI Program 2 5 Disconnecting the CPI Cables Warning The sensor camera cable must be disconnected before the power dsp cable If you do not disconnect the sensor camera cable first you may damage your CPI CPI cables must be disconnected in the reverse of the sequence in which they were connected as follows 1 Verify that the Sensor Power switch on the front of the data acquisition system is switched off Verify that the Data Acquisition System Computer is switched off 2 Disconnect the sensor camera cable from J1 on the Data Acquisition Computer 3 Disconnect the sensor camera cable from J1 on the Sensor
9. SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 21 SPEC CPI Preliminary Technical Manual 4 067 63 273 ROI Locations Ca Top Left Locations Bottom Right Locations Y pixels o 100 200 300 400 500 600 700 800 900 1000 X pixels Figure 5 1 18 ROI x y location plot To enable the ROI x y plot check the Plot it box in the ROI X Y Plot section of the Disp Hist tab of the Settings window of Figure 5 1 15 The plot will open when the first ROI is found in an image after checking the Plot it box The plot will continue adding red and green markers with each ROI until the Max ROIs in Plot number of ROIs is displayed If Reset Plot When Filled box is checked the plot will be cleared and begin updating again as if just opened If not checked the plot will stop updating once the maximum number of ROIs is plotted 5 1 7 cpi INI File Description The cpi INI file is opened and its information used each time the CPl exe program is started Additionally information is recorded into this file each time the CPl exe program is stopped by the user reflecting changes in operation parameters since the program was started WARNING The format of the cpi INI file is critical Manipulation of the file manually though some times necessary must be performed carefully Incorrect format of the cpi INI file can cause the
10. as it does not require removal of the entire internal sensor head 1 Before rotating the PCB verify CPI power is switched off 2 Using a 5 32 ball driver of hex wrench loosen the PCB retaining screw that holds the PCB retaining clip Figure 6 2 1 SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 122 SPEC CPI Preliminary Technical Manual 3 Rotate the PCB retaining screw away from the PCB Figure 6 2 2 4 Before accessing the PCB to perform any troubleshooting make sure proper precautions to avoid electrostatic discharge ESD are followed Figure 6 2 3 5 Rotate the PCB outward to gain access for troubleshooting Figure 6 2 4 6 When the PCB is in a stable position sensor head power can be switched on 7 When troubleshooting is complete turn off sensor head power Rotate the PCB back into position verifying the PCB aligns with the machined slots in the instrument frame located at the rear of the PCB mounting location Figure 6 2 5 8 Rotate the retaining clip back into position and tighten the clip retaining screw N N Beets S s D q am Pii j iy F fam 5 32 BALL DRIVER ENG JAE on HEX WRENCH AF PCB RETAINING CLIP ROTATE PCB RETAINING PCB RETAINING SCREW CLIP AWAY FROM PCB eats Figure 6 2 1 Figure 6 2 2 FOLLOW PROPER ESD PRECAUTIONS BEFORE WORKING ON PCB 7
11. 0 90 0 0 t t te APD_45 Amplifier POS 45 Laser Power Actual 876 19 939 miw APD_ SO Amplifier POS 45 Detector DC Level 880 4 2768 W Imaging Laser Pulser POS 90 Laser Power Actual 1091 26 065 miw POS_45 Laser POS 90 Detector DE Level 1089 5 2925 Y POS_SU Laser Img Laser Current Actual 345 33 0591 Y Img Laser Pulse Width Actual 262 22 9560 VY 5 Wol Supply M J B pE J cy 4 9365 W 4 9039 W De lce Heat tT Pop lt o D ii Oo n ai UU a 12 Wolt Supply 2411 12 3095 Y POS 45 Laser Power Set 2123 20 154 mw POS _45 Threshold Set 167 0 1019 POS 90 Laser Power Set 2654 26 409 miw POS _90 Threshold Set 167 0 1019 Imaging Current Setpoint S668 33 0517 Imaging Pulse Width Setpoint 2427 22 6997 Y blinimum Transit Time 35 r 292e 007 g0 AFD Amplifier Temp 929 29 1 deg C REF102 Mre 0 Wols Pressure Sensor pst SLS Laser Setpoint rv PMT Voltage ba Pylon Cover Patch Temp g Laser Trig Timer Thresh aa EEC Diagnostic Mode Experts LAS AA etc baie allls Laser Trigger Time Threshold 0 sec SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice h MANGAS AAA Ausilar Serial Input 4 2 1 p i T HE 0 1904 Kh Li 70 SPEC CPI Preliminary Technical Manual Figure 5 1 3 Housekeeping window SPEC Inc reserves the right to make
12. 1 3b Figures 4 1 3c and 4 1 3d are ray traces for the scattered light path propagating through the 90 PDS collection optics A particle must be present in the 90 PDS beam to scatter light around the dump spot Figure 4 1 3c shows the scattered light path for the X Z plane and Figure 4 1 3d shows the scattered light path for the Y Z plane The effect of the dump spot can be seen in both these ray traces by noticing the shadowed area just to the right of the dump spot The minimum collection angle of 2 5 is defined by the rays that just pass around the dump spot in Figure 4 1 3c The maximum angle of 8 2 is defined by the maximum clear aperture of 90 PDS Collection Lens2 The relay lenses are used to accommodate the mechanical packaging of the collection optics by increasing the total path length The APD Focusing Lens is used to focus the scattered light rays onto the 1 5 mm diameter active area of the detector SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 39 SPEC CPI Preliminary Technical Manual 90 PDS Sue COLLECTION fi aons SPOT RELAY1 RELAY2 90 APD 90 PDS SAMPLE COLLECTION FOCUSING DETECTOR VOLUME 19 LENS SCA AN AN A a PATH NY NW X Z PLANE AN A LASER KITA b BEAM ms PATH 39 9 2 50 68 7 Y Z PLANE ELEMENT SPACING IN mm SCATTERED LIGHT PATH c X Z PLANE SCATTERED LIGHT l d PATH Y Z PLANE A F 36 mm oF mmx
13. 2 5 for a full list of set mode parameters The DSP board utilizes an Analog Devices ADSP2191 Digital Signal Processor to control and monitor the probe hardware This DSP has a bi directional high speed universal asynchronous receiver transmitter serial port interfaced to either RS 422 or RS 232 level drivers and receivers user selected using jumpers J3 J4 J5 J6 and J7 The jumpers should short pins 1 and 2 pin one is identified by a square solder pad on the bottom of the board for RS 422 interfaces recommended or short pins 2 and 3 for RS 232 interfaces The asynchronous communications lines interface directly to a serial port on the host computer receiving commands from the host and transmitting data to it as described below Three types of data packets are currently output from the sensor head probe and four types are received The transmitted packets are the PDS or PDS with SLS packet that is transmitted when a particle is detected and the housekeeping packet Table 4 2 3 which is transmitted once per second The format of the PDS packet is given in Table 4 2 1 The PDS with SLS packet is found in Table 4 2 2 Table 4 2 1 PDS packet format Packet Sync Word 0x4450 Packet Length 12 Packet Type 0x5050 UTC Seconds of Year LSW UTC Seconds of Year MSW 6 _ Arrival time of 62 5 ms periods into SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without
14. 5 16 SCREWS CAPTIVE FOR J205 AND J215 SMALL FLAT BLADE SCREWS SCREW DRIVER REMOVED FOR J225 gt J205 MATE 7 DC POWER CONNECTORS J20S J21S J22S J22S DSP DATA Figure 6 5 17 Figure 6 5 18 CAMERA _ CONNECTOR J23S INTERNAL PYLON Figure 6 5 19 SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 140 SPEC CPI Preliminary Technical Manual Figure 6 5 20 6 6 Pylon Cover Installation The CPI sensor head pylon cover must be installed for airborne operation of the CPI sensor head The following photographs show the sensor head lying flat on a table The pylon should always be placed on a soft material such as foam to avoid scratching the outer surface The following procedure should also be used when the sensor head is mounted on an aircraft CAUTION The CPI pylon is a high performance assembly that serves as a protective housing for the internal sensor head components and as the structural interface to the aircraft It is hermetically sealed up to approximately 65 000 ft altitude O rings and precision machined surfaces are used to achieve this seal Improper disassembly assembly of the pylon or mishandling of the components can result in damage that will compromise the pressure integrity of the pylon This may result in malfunctioning of the instrument during flight Disassembly Assembly of the pylon should only be p
15. 5 SOFTWARE DESCRIPTION AND REAL TIME OPERATION ccsscsccssssssssssssssssceseees 63 5 1 Data System Overview 5 1 1 View Menu 5 1 1 1 Housekeeping Window 5 1 1 2 Stats Window 5 1 2 Setting Menu 5 1 2 1 Advanced Control and Settings Window 5 1 3 Particle Detection System Control and Monitoring 5 1 3 1 PDS Laser Power and DC Level 5 1 3 2 PDS Threshold Control 5 1 3 3 PDS Minimum Transit Time Control 5 1 4 Image Collection and Monitoring 5 1 4 1 Background Images and Parameters 5 1 4 2 Particle Collection and Associated Controls 5 1 4 3 Image and Background Mean Settings 5 1 4 4 Live Video Mode 5 1 5 Probe Sensor Head Thermal Control 5 1 6 Display Options 5 1 6 1 Rates and Image Parameters 5 1 6 2 Displays Histograms and ROI X Y Plots 5 1 7 CPI INI File Description 5 1 7 1 Enunciator Panel 5 2 CPI Real Time Operation and Troubleshooting 5 2 1 Operation and Troubleshooting in Flight 5 2 2 RTIA Log Troubleshooting 5 2 2 1 Sensor Head Powered Off Camera Connector Disconnected 5 2 2 2 No Hardware Key Connected 5 2 2 3 Imaging Laser Power Too Low or Too High 5 2 3 Background Troubleshooting 5 2 3 1 What To Do If No Background is Acquired at Startup 5 2 3 2 What to Do if Probe is Communicating With DAS but No Background Taken 5 2 4 PDS Operation and Troubleshooting 5 2 4 1 What To Do If PDS Laser Power Needs Adjustment 5 2 4 2 What to Do if the PDS Threshold Needs Adjustment 5 2 4 3 What to Do If the PDS Minimum Transit Time Needs Adj
16. 80 160 No See Section 5 2 3 2 and adjust the background and image means See section 5 2 3 2 And adjust the Imaging laser power Figure 5 2 2 Background image troubleshooting flowchart 5 2 3 2 What To Do If Probe Is Communicating With DAS but No Background Taken If the Background Invalid enunciator is flashing or if the background image has a very low or high image mean which varies from probe to probe steps can be taken to improve the background SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice LOZ SPEC CPI Preliminary Technical Manual High Particle Concentration The first type of problem that can occur is the DAS attempting to get a background while in the presence of high particle concentrations The DAS waits until there are less than Strobes Threshold number of PDS events per second before attempting to get a background see Figure 5 2 3 ex FSET plc 167 PDSa0 Ki U 67 Farticle Threshold Min Size Pixels Minimum Transit Time 6re 00 ee Background Options Bkground Rate secs B0 Strobes Threshold 10 z HEATERS APPLY Figure 5 2 3 The probe tab of the settings window Raising the Strobes Threshold value does not improve the likelihood of getting a valid background while in high particle concentrations because the background validation process will reject images that have a particle prese
17. AND SENSOR CONNECTORS Figure 6 6 10 Figure 6 6 11 SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 144 SPEC CPI Preliminary Technical Manual Figure 6 6 12 6 7 Cleaning CPI Optical Windows During normal airborne operation the optical windows of the CPI will become contaminated due to cloud drops and streaming water Contamination on the windows of the imaging system can result in a decreased image mean and a severely contaminated background over time Small levels of contamination on the PDS system windows can result in an increased detector DC level Figure 6 7 1 due to light scattering around the dump spot caused by the contaminants In an extreme case a large amount of contamination could reduce the detector DC level by blocking most of the laser light During normal operation the laser power levels can be gradually reduced as contamination increases to lower the PDS detector DC levels When the lasers are being operated at less than half power 20 mW set point the PDS windows should be cleaned The following procedure describes how to properly clean the windows The real time software must be operated during cleaning of the windows to provide feedback that the correct result is being obtained Warning The CPI optical windows are made of sapphire and coated with a high performance anti reflective AR coating The windows are bonded into the op
18. AND SENSOR e zA ai l _ all 4 ES PDS 90 fe HEATER AND SENSOR Ne hoai OPTICAL BLOCK HEATERS AND SENSORS CAMERA TEMPERATURE SENSOR i Figure 3 1 8 Photograph of heat zone locations on rear side of internal sensor Figures 3 1 7 and 3 1 8 show various heat zone locations for the CPI internal sensor There are two Avalanche Photodiode Detectors APDs in the system PDS 45 and PDS 90 but only one heat zone is used for control of the APDs A sensor is on the PDS 90 APD and heaters are on both the PDS90 and PDS 45 APD Each of the three laser assemblies has its own heat zone The camera temperature sensor monitors the camera temperature but does not have a heater associated with it SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice gt SPEC CPI Preliminary Technical Manual 4 0 THEORY OF OPERATION 4 1 Optical System Description The overall optical system consists of three separate subsystems the 45 Particle Detection System PDS the 90 PDS system and the imaging system Figure 1 1 2 is a functional schematic for the CPI optical system For the sake of clarity only the major components of each system are shown in the figure The PDS system is used to detect the presence of a particle in the sample volume The CPI DSP electronics process the particle information If certain triggering criteria are satisfied pulse height mini
19. BLADE _ NREMOVE SCREWS THEN SCREW DRIVER DEMATE CONNECTORS J20S AC POWER J21S DC POWER J22S DSP DATA Figure 6 3 4 Figure 6 3 5 SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice La SPEC CPI Preliminary Technical Manual SCREWS CAPTIVE FOR J205 AND J215 SCREWS REMOVED FOR J225 AFTER LOOSENING REMOVING SCREWS DEMATE CONNECTORS J205 J215 J225 Figure 6 3 6 TORX PLUS gt FASTENERS po Z i Pe 7 Figure 6 3 7 PULLLING FORK TOOL tr a ALIGN SLOT IN PULLING FORK WITH PYLON AND AFT SAMPLE TUBE PRY BOSSES AFT SAMPLE TUBE PYLON PRY PRY BOSSES BOSS Figure 6 3 9 Figure 6 3 10 SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 128 SPEC CPI Preliminary Technical Manual TE Wut y A PULL BACK ON LI FORK A PULL DIRECTION PULL ON GREEN HANDLE WITH HAND MAXIMUM PULLING POINT AFT SAMPLE TUBE O RINGS EXPOSED DURING REMOVAL GROMMET ON PYLON SPREADER REMOVAL DIRECTION GAP DEVELOPS BETWEEN PYLON SPREADER AND INTERNAL SENSOR AS SENSOR IS REMOVED Figure 6 3 15 1 PYLON SPREADER AFT SAMPLE TUBE SLIDES OUT FROM INTERNAL SENSOR INLET ADAPTER S FIXED TO PYLON i i F 7a INTERNA
20. DAS program to fail to communicate correctly with the probe or even to start Therefore always back up the cpi INI file before making changes SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 22 SPEC CPI Preliminary Technical Manual The cpi INI file is located in the c winnt directory Editing may be done using the Windows Notepad program A copy of a sample cpi INI file is included in appendix Section 7 3 and has line numbers added for reference that are not in the standard cpi INI file These are for reference only and should not be added to the actual file The cpi INI file records the set point value of all parameters accessed from the CPl exe program Most changes to the cpi INI file occur when the user adjusts a parameter eg in Advanced control and settings window during real time operation and then stops data acquisition by hitting the stop probe button and exits the program some parameters in the cpi INI file however must be changed within the file directly and will be carefully discussed below The cpi INI file is separated into sections each delimited by brackets For example on line 1 System indicates to the DAS program that it will find information related to the current system here The parameters under System come factory configured and should not be changed by the user Likewise the parameters under the next heading ROI Param
21. Description PDS DETECTOR INTERNAL SENSOR HEAD DSP CONTROL BOARD Figure 3 1 1 Photograph of CPI sensor head with pylon cover removed Figure 3 1 1 is a photograph of the CPI sensor head with the pylon cover removed See Section 6 1 Pylon Cover Removal The sensor head consists of the pylon and internal sensor The internal sensor contains all of the electro optical components and electronics and the pylon serves as a protective housing for the internal sensor For laboratory operation or troubleshooting the internal sensor can be removed from the pylon and operated independently Figure 3 1 2 shows the various components of the CPI sensor head sample tube The direction of airflow is from right to left in Figure 3 1 2 The sample volume is located in the optical block just downstream of the forward sample tube A detailed drawing of the flow geometry is included in Appendix 7 2 Each of the sample tube components has an associated heat zone that is controlled from the advanced control and settings window in the real time software Figure 3 1 3 is a photograph of the CPI sensor head showing the physical location of the various components of the sample tube SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 29 SPEC CPI Preliminary Technical Manual PYLON NOSE CONE FORWARD CENTRAL OPTICAL SAMPLE AFT SAMPLE SAMPLE TUBE BLOCK TUBE
22. Head SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 29 SPEC CPI Preliminary Technical Manual Disconnect the power dsp cable from J2 on the Data Acquisition Computer Disconnect the power dsp cable from J2 on the Sensor Head Disconnect mouse keyboard and monitor from the back of the Data Acquisition Computer Disconnect the three AC power cables Computer Power AC1 AC2 2 6 Packing CPI System This procedure is to be followed when packing the CPI system for shipment or storage 20 21 22 23 24 20 26 21 28 Place the foam insert into the shipping case for the CPI pylon Figure 2 6 1 Place the pylon plug over the inlet and outlet of the CPI pylon to keep dust out during shipping Figure 2 6 2 Place the CPI pylon in the shipping container and cover with the foam insert with the circular cutout as shown in Figure 2 6 3 Be sure the CPI pylon is in the same orientation as Figure 2 6 2 Place the CPI cables into the circular cutout as shown in Figure 2 6 4 Close and latch this shipping case Remove the AcquireNow Hardware key and then disconnect the captive cables from the back of the data system Figure 2 6 5 This step is optional but provides more protection during shipping of the computer Remove the three screws for the computer cover as shown in Figure 2 6 6 and remove the computer cover Insert the foam
23. Limit SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice IG SPEC CPI Preliminary Technical Manual Figure 5 1 20 Section of HouseKeeping window showing out of range parameters Provided the alarm limits have been set to reasonable values these out of range parameters indicate a problem The pylon cover patch heater may not be selected on for instance in the advanced control and settings window If the user enables this heater the pylon cover patch temperature should increase and the blue alarm should go away If the heater is already enabled perhaps the AC2 circuit breaker is off and there is no AC heater power present there would be many blue temperatures in this case For the over range parameter in Figure 5 1 20 the Imaging Lens Temp the heater may be experiencing normal thermal overshoot In this case the upper alarm limit should be increased because this is a false alarm The set point may be 25 C and the actual temperature overshoots to 27 C as the heater pulses on for one second A problematic over temperature condition could occur for example if a temperature sensor became unattached from its particular heat zone Another example of an incorrect alarm range could be the pylon temperature alarm limits of 5 C and 35C shown on line 135 of the cpi INI file This heat zone may have a lower limit that is often exceeded during flights i
24. Lov ZO ae Zo Ad Se co ile S28 Sou 34 Se DOs Sts 28 Gio AQ ee As 43 44 45 46 47 48 49 Dh collie SAS Da 54 Dos SO Oi ore ote 60 6 622 63 64 Gor 66 OL SPEC CPI Preliminary Technical Manual ROTAspectRatio 640 2 900 ROITFillRatio 0 000006 0 000000 0 800000 ROIXPad 15 0 50 ROTYPad 6 0 50 DebugMode 0 FullFrame Skips 0 0 10000 Probe Settings Mode 3 Heaters 16383 Heaters2 0 settingl Forward Sample Tube Temp set point Setting 95 7 0 957 setting2 is the Upper Optical Block Temp set point Setting2 957 108 1057 setting3 is the Lower Optical Block Temp set point Ssetting3 957 108 L057 setting 4 is the Central Sample Tube Temp set point Setting4 1036 108 1057 settingsS is the Aft Sample Tube Temp set point Setting5 1057 64 1057 setting 6 is the nose temp set point Setting6o 957 64 957 Setting 7 is the pylon temp set point Setting7 1057 64 1057 setting 8 is the camera temp set point currently has no heater installed Setting8 813 64 1057 setting 9 is the APD45 temp set point Setting I L0S7 Loe LOs7 l setting 10 is the electronics temp set point currently no heater anstalled Settingl0 241 64 1057 setting 11 is the imaging laser temp set point Settingilil Z296 290 1057 setting 12 is the PDS45 laser temp set point Setting l2 290 290 1057 setting 13 is the PDS90 laser temp set point Setting1l3 298 290 1057 se
25. System Box The DSP board is the main control center of the Sensor Head It contains the ADSP 2191 digital signal processor microcomputer and logic chips Together these circuits manage particle detection laser drive power heater control and the collection and reporting of housekeeping data to the Data Acquisition System These processes are described in the following sections 4 2 14 Particle Detection System PDS The particle detection system consists of two particle detection lasers and two Avalanche Photodiode Detectors APDs Please refer to the Optical Assembly description for the laser related part of the PDS The two APDs are designated PDS 45 detector and PDS 90 detector to indicate from which laser they receive light Only the PDS 45 detector circuitry is described here but the PDS 90 circuitry is identical See SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 48 SPEC CPI Preliminary Technical Manual Figure 4 2 1 the block diagram of the PDS 45 analog electronics found in the schematics of Appendix 7 1 The analog processing electronics in the PDS 45 detector circuit high pass filters the APD output pulse and then feeds it to a comparator which generates a clean digital logic pulse as shown in Figure 4 2 2 A Hamamatsu Avalanche Photo Diode APD based detector with an on board thermoelectric cooler part number C5460 is used to sense scattered light
26. Technical Manual Figure 5 1 6 The Advanced Control and Settings Window Adjusting the slider bar has the benefit of only allowing the user to choose set point values that are within the allowed limits as set in the cpi INI file discussed in section 5 1 7 If manually entering values via the first option a user entered number may exceed the allowed limits generating an error window and requiring the user to try another value Focusing again on the left side of the window a check box labeled Recording Disabled is visible checked in the Figure 5 1 6 If checked the data system will not record any activity All housekeeping image and PDS information received by the DAS will be visible to the user via the GUI but no data will be recorded If recording is disabled the user is warned via a red enunciator in the main window as seen in Figure 5 1 1 The Drive For Next File selection tool located mid to lower left in the window allows the user to choose to which storage drive the data files should go on the DAS computer The Drive Count selection tool allows multiple drives to be used for data recording after the initial drive is full The Enable Cycling of Settings Image Laser Trig Timer Thresh and Diagnostic Mode radio buttons located in the lower left of the window are under development and should always be left disabled as shown The Apply button is context sensitive if the probe and DAS are not
27. adapter and pylon spreader Assist the sliding of the internal sensor by pulling on the green handle Figure 6 3 11 with your available hand in the same direction as you are pulling with the fork If the pylon is not mounted on an aircraft have another person steady the pylon if it begins to move 15 Figure 6 3 12 shows the direction the components will begin to move 16 Figure 6 3 13 shows the aft sample tube O rings that will be exposed as the aft sample tube slides back 17 Figure 6 3 14 shows the inlet adapter O ring that will be exposed as the internal sensor slides back SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 129 20 21 22 23 24 20 26 21 SPEC CPI Preliminary Technical Manual Figure 6 3 15 shows the gap that will develop between the internal sensor and pylon spreader grommet as the internal sensor slides back Continue pulling back on the CPI pulling fork until the maximum pulling point is reached Figure 6 3 11 Both O rings on the inboard end of the aft sample tube should be almost completely exposed by this time Figure 6 3 16 By hand slide the aft sample tube into the farthest back position shown in Figure 6 3 16 Figure 6 3 17 shows the PDS 45 laser and Delrin laser guard on the internal sensor The Delrin laser guard protects the PDS 45 laser from colliding with the pylon screw boss If the PDS
28. adjustment of the imaging laser current remember to click the Apply button will change the image brightness displayed and reported Once the image mean is at a desirable value e g somewhere between 80 and 160 though this is different for each probe turn off live video by unchecking the Live Video box A new background should be taken immediately after any changes are made to the imaging laser set points f not the background subtraction will now have a large offset due to the changed image mean causing the particle processing algorithm to work poorly or not at all Warning If the image mean is outside the limits set in the Advanced Control and Settings window shown in Figure 5 2 4 live video will fail to update the Display window and the probe will fail to take a background To prevent the image mean from falling outside the limits set Min Img Mean equal to 1 and the Max Img Mean equal to 255 when troubleshooting image mean problems Be sure to return the limits to a proper operating range when you are finished diagnosing and correcting the image mean problem 9 2 4 PDS Operation and Troubleshooting The PDS system is described in detail in Section 5 1 3 Particle Detection System Control and Monitoring The flowchart of Figure 5 2 7 is a guide to troubleshooting any problems with this system The user adjustable parameters for the PDS system are as follows 8 PDS 45 laser power 9 PDS
29. and this laser has fired by driving the PDS STATUS signal high The PDS STATUS signal is received by the frame grabber and is used by the data acquisition system to determine whether the next image frame it receives contains at least one particle or not e State 3 The DSP is a microprocessor that resides in the sensor head of the CPI Notify the digital signal processor DSP that a particle was seen so that it can send a PDS packet to the data acquisition system A PDS data packet accompanies each particle image with particle specific information such as the voltage pulse height that was output from each of the PDS detectors Wait in this state and don t allow any more particles to be imaged until an EXSYNC pulse is received from the frame grabber in the data acquisition system SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 3 SPEC CPI Preliminary Technical Manual The EXSYNC pulse causes the camera to download its current image to the data acquisition computer It also tells the sensor head electronics that the camera and data acquisition computer are ready to take the next picture e State 4 Perform some of the operations to reset the sensor head electronics in preparation for the next particle Wait for the CLEAR HOLD signal from the DSP This signal tells the state machine that the DSP is ready for the next particle e State 5 Go to state 6 e Sta
30. blocks included in the original shipment into the computer case for added protection during shipping Place the foam blocks in the location shown in Figure 2 6 7 Replace the three screws for the computer cover Replace the computer cover Place the data system and other accessories in the shipping case as shown in Figure 2 6 8 The atomizer should be wrapped in bubble wrap Place the foam insert shown in Figure 2 6 9 on top of the data system SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 26 SPEC CPI Preliminary Technical Manual 29 Place the flat panel monitor keyboard mouse cleaning tool manual pulling fork and alignment pin into the foam insert as shown in Figure 2 6 10 The alignment pin should be wrapped in bubble wrap 30 Close and latch the lid to the shipping container 31 The system is now ready for shipping Figure 2 6 1 6 3 a Figure 2 6 4 SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 2d SPEC CPI Preliminary Technical Manual Figure 2 6 7 Figure 2 6 8 Figure 2 6 9 Figure 2 6 10 SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 28 SPEC CPI Preliminary Technical Manual 3 0 CPI PHYSICAL DESCRIPTION 3 1 CPI Sensor Head Physical
31. cleaning If the image mean decreases or more contaminants are present in the CCD image repeat the cleaning procedure 45 Cleaning of the windows can occur when the probe is mounted to an aircraft or in the laboratory in or out of the pylon The nose cone can be removed see Pylon Cover Removal Procedure to improve access to the optical windows Replace the nose cone after cleaning 46 The exact location of the windows depends on the orientation of the probe This is critical for identifying which window is being cleaned Figure 6 7 8 and Figure 6 7 9 show the internal sensor removed from the pylon in the laboratory with the input windows on top and the output windows on the bottom The PDS 90 input window is on the right and the output window is on the left in these figures If the probe is hanging upside down on an aircraft all the positions will be flipped 180 degrees Use Figure 6 7 6 Figure 6 7 8 and Figure 6 7 9 as a reference to locate the windows in any situation SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice Lay SPEC CPI Preliminary Technical Manual I Recording PDS Det Disabled Invabd Settings xi ENUNCIATOR ALARM PDS 45 DC LEVEL ALARM DETECTOR NEAR SATURATION LASER SET POINT AT FULL POWER Figure 6 7 1 Enunciator panel shows PDS Det Invalid and settings window showing saturated PDS DC levels DELRIN CLEANIN
32. communicating it will read Apply and Acquire Regardless of what is displayed on the button if a change is made to any of the settings in this window the Apply button must be clicked to make the changes active Clicking on the Stop Acquisition button is the same as clicking the Stop Probe button located in the main screen both will stop communications with the sensor head However if power is maintained to the sensor head the last commanded settings will continue to be observed and the probe will continue operating The DAS will ignore any communications and the GUI will not update with housekeeping or image data The Restore Defaults button retrieves all the saved settings from a default file called cpi_restore_defaults INI located in the same directory as the cpi INI file The cpi_restore_defaults INI file matches the cpi INI file when the CPI is originally configured Users should customize the cpi INI file to have temperature set points and alarm limits appropriate for the operating environment of that particular instrument see Section 5 1 7 Users are encouraged to store a copy of the customized cpi INI file with safe settings such as a large PDS threshold value described later as the cpi_restore_defaults INI file for quick restoration of safe operating parameters for the CPI system The rest of the parameters in the window will be discussed in the sections covering the PDS and Image Control systems Para
33. dsp to the Data Acquisition System te m SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice Lo SPEC CPI Preliminary Technical Manual Figure 2 2 5 Connecting the framegrabber to the Data Acquisition System g d POWER DSP CONNECT COMPUTER POWER KEYBOARD MOUSE SCREEN AND SENSOR AC1 amp AC2 POWER Figure 2 2 6 Connecting the mouse keyboard power supply screen and sensor AC1 and AC2 SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice LG SPEC CPI Preliminary Technical Manual Te se CONNECT 28VDC POWER LAST Figure 2 2 7 Connecting 28 VDC to back of Data Acquisition System SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 17 SPEC CPI Preliminary Technical Manual Figure 2 2 8 Connecting the power dsp cable to the sensor Head SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 18 SPEC CPI Preliminary Technical Manual CONNECT J1 SENSOR CAMERA AFTER J2 SENSOR POWER DSP IS CONNECTED g yemte Se Figure 2 2 9 Connecting the sensor camera cable to the Sensor Head 2 3 CPI Atomizer Setup for Laboratory Testing 1 Verify CPI has been co
34. due to particles passing through the PDS 45 laser beam The output is fed into a resistor divider R54 and R17 which scales the voltage down by a factor of 0 755 This voltage is buffered through U15A and the output fed to a low pass and to a high pass filter The low pass filter scales the voltage down again permitting DC monitoring of the PDS signal at the output of U16 pin 1 with a limit of 3V max at the output This signal goes to an analog to digital A D converter and the DSP sends the corresponding digital value to the data Acquisition system in the housekeeping packet The high pass filter blocks the DC component with capacitor C22 whose output is baseline restored by transistor Q4 The baseline restored signal is input to U17 where the gain brings the AC signal amplitude back up to 0 95 times the APD detector output The output of U17 is due to the described circuitry a baseline restored AC coupled analog signal which should go positive when a particle passes through the PDS 45 laser beam with an amplitude determined by the particle s scattering cross sectional area the PDS 45 laser intensity and the APD sensitivity This signal is compared with a PDS 45 threshold voltage which is user programmable at comparator U18 The AC coupled signal the comparator threshold and the comparator output are shown in Figure 4 2 2 The comparator output which is a clean digital pulse is then sent to the digital logic IC U20 The output of U17 des
35. hh ROTATE PCB OUTWARD M TO GAIN ACCESS FOR TROUBLESHOOTING Figure 6 2 3 Figure 6 2 4 SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice Lag SPEC CPI Preliminary Technical Manual WHEN ROTATING PCB BACK INTO LOCKED POSITION MAKE SURE BOARD ALIGNS WITH MACHINED SLOTS Figure 6 2 5 6 3 CPI Internal Sensor Removal The CPI internal sensor must be removed from the pylon to perform various optical adjustments that cannot be performed in the pylon or to perform troubleshooting that cannot be accomplished with the internal sensor mounted in the pylon If the CPI is mounted to an aircraft removal of the internal sensor head does not require removal of the pylon from the aircraft The photographs show the sensor head lying flat on a table but the same procedure is followed if it is mounted on an aircraft The pylon should always be placed on a soft material such as foam to avoid scratching the outer surface Warning The CPI internal sensor head is a high performance assembly that consists of many optical components electro optics assemblies and ESD sensitive electronics The pylon serves as a protective housing for the internal sensor head When the internal sensor head is removed from the pylon the optics are no longer protected from contamination The internal sensor head should be worked on in a dust free ESD protected environm
36. improvements and changes to the CPI and related software at any time and without notice TA SPEC CPI Preliminary Technical Manual 5 1 1 2 Stats Window selecting Stats Window in the View menu opens the statistics window shown in Figure 5 1 4 This window contains a set of parameters of interest to the user Frame Particle Opa Interval sec Frm Captured 0 0 Imaged Particles Last Frame Img Mean 122 Bka Mean Tee E ackgrounds a7 Figure 5 1 4 Statistics window Items in the section of the statistics window labeled Last Frame are discussed in Section 5 1 4 covering image collection control and monitoring The items in the upper portion of the window are updated at the user selected interval in seconds which is the first item in the Frame Particle and Other Rates section The user also enters air speed here in meters per second for use in deriving parameters such as particle concentrations The true air speed has no other function and entering values that do not match the speed of the craft on which the CPI is located will not affect its operation The Frms Captured Frms Attempted and Valid Frms fields refer to the number of frames the DAS has received in the last Interval period in which a valid ROI was found the number of frames total received in the same period with and without ROIs and the percentage of valid frames equal to frames captured frames attempted
37. in this case and tell the DAS that if the derived temperature is less than 10 or greater than 35 degrees Centigrade for the Forward Sample Tube flash a blue if less than lower limit or red if greater than upper limit alarm in the housekeeping window A yellow invalid temperature light will also appear in the enunciator panel see red enunciator windows near the top of Figure 5 1 1 Returning to lines 26 and 27 of the cp INI file note that items 2 and 3 are limits given in ADC values For the given values of 0 and 957 the Forward Sample Tube temperature set point has the range Upper 957 x 0 029356 1 8775 29 97 C Lower 0 x 0 029356 1 8775 1 8775 C SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 94 SPEC CPI Preliminary Technical Manual The effect of these settings is such that from within the CPl exe program users may change the Forward Sample Tube set point to be any value from 1 8775 to 29 97 degrees centigrade If the probe reports back any temperature below 10 degrees C or above 35 degrees C the DAS should display warning enunciator indicators to the user Other parameters may be changed that have different units such as Volts or milliWatts but the procedure is the same To determine the units find the parameter in the housekeeping window For example the PDS45 Laser Power is reported with units of mW milliWatts The settings f
38. ini ll 23 958 i PP ll 23 958 SLS Laser Temp C 0146484 SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 0 1 ON SPEC CPI Preliminary Technical Manual a eee eee Inside Air Temp C 0 02935559 2 Cee Camera Teme C anong 23 958 P meonta Tomes 2a 950 2 23 958 Z esistere O case A 23 958 B RR Se teerTeme O aa ogp 23 958 24 PDS_45 Laser Power mW_ O 0 0177557 25 PDS_45 Detector DC level 0 00439451 26 PDS_90 Laser Power mW_ O 0 0177557 27 PDS_90 Detector DC level O _ 00439451 Imaging Laser Pulse Width 0 02050781 Volts 30 5VoltSupply Volts Of 00292969 31 5VoltSupply Volts O 00292969 00735352 00735352 Probe Mode Bit Mapped Bit O set gt De ice Heat on Bit 1 set gt Unused Bits 2 gt Probe Reset Bit 3 gt 1 equals enable the imaging laser trigger timer threshold feature see word 35 Bit 4 gt 1 equals enable diagnostic mode 32 33 34 for diagnostics only should be hard to set Bits 5 7 gt unused Bits 8 15 Command 35 Heater Status Bit Mapped 1 on Bit 0 gt Forward Sample Tube Bit 1 gt Upper Optics Block Bit 2 gt Lower Optics Block SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 58 SPEC CPI Preliminary Technical Manual B
39. installation 25 After operation of the CPI has been verified turn off the sensor power and proceed to the pylon cover installation procedure VERIFY AFT TUBE IN THIS INLET ADAPTER POSITION _ FIXED MOUNT POINT AFT SAMPLE TUBE CAPTIVE TO PYLON F REMOVE INTERNAL SENSOR FROM TEST STAND FOLLOWING PROPER PROCEDURE ee a PYLON SPREADER FIXED MOUNT POINT PYLON CONNECTORS CAPTIVE TO PYLON Figure 6 5 1 Figure 6 5 2 Figure 6 5 3 SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice L7 SPEC CPI Preliminary Technical Manual PIVOT AROUND LASER GUARD DELRIN LASER GUARD CAUTION 45 PDS LASER A P DO NOT BUMP 45 PDS LASER ALIGNMENT MAY BE AFFECTED i rs i q l bi y Y INTERNAL SENSOR PYLON SCREW BOSS Fe ROTATE MUST ALIGN WITH BOTTOM OF INLET ADAPTER SENSOR AROUND i LASER GUARD gt id VS 4 x j Figure 6 5 4 Figure 6 5 5 INLET ADAPTER MUST ALIGN WITH INTERNAL SENSOR BEFORE SLIDING FORWARD Figure 6 5 6 _ PYLON SPREADER AFT SAMPLE TUBE SLIDES INLET ADAPTER IS FORWARD INTO INTERNAL SENSOR WITH GROMMET FIXED TO PYLON INSTALLATION DIRECTION PYLON SPREADER IS FIXED TO PYLON INTERNAL SENSOR SLIDES ONTO PYLON SPREADER AND INLET ADAPTER INTERNAL SENSOR SURFACE MUST BE BELOW GROMMET Figure 6 5 7
40. laser to flash the instant a particle is in the imaging system object plane A CCD camera records the particle image s and the frame containing the particle s is sent to an image processing system that locates the particle s in the image and cuts out these regions of interest ROI for display and recording Electronics in the sensor monitor and control numerous parameters as dictated by the software in the Data Acquisition System The imaging system utilizes a 1024 x 1024 pixel monochrome digital camera that has eight bits of resolution 256 levels and has an effective pixel size of 2 3 microns The camera can download approximately 72 frames per second allowing the instrument to rapidly image small cloud particles 1 1 2 1 Instrument Behavior With No Particle Present Figure 1 1 2 shows the primary electro optical components in the CPI The upper left diagram shows a cut away view of the CPI sample volume Two ribbon shaped intersecting laser beams form the particle detection system PDS sensitive area Both PDSs are functionally identical The PDSs use a continuous wave laser and beam shaping optics that produce laser beams with a rectangular cross section The two PDS laser beams are orthogonal to one another and form a volume of approximately 2 5 mm x 2 5 mm x 0 5 mm located in the center of the instrument sample tube and tilted at an angle of 45 degrees to the particle trajectory Each rectangular laser beam is dumped onto a dump spot before it
41. mm x 2 mm The minor axis of the elliptical beam is then compressed using a pair of cylindrical lenses In Figure 4 2 2 the minor axis is referred to as the x axis and the major axis is referred to as the y axis The beam is compressed by the ratio of the focal lengths of the cylindrical lenses In this case the compression is 5 25 or 0 2X This reduces the minor axis of the ellipse to approximately 0 4 0 5 mm The beam shape is now closer to rectangular than elliptical Since the cylindrical lenses do not affect the y dimension of the beam a rectangular aperture is used to reduce the beam to the desired 2 5 mm dimension The width of the aperture is 1 mm to allow the laser beam to cleanly pass through in the x dimension SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 38 SPEC CPI Preliminary Technical Manual The PDS lasers and the beam shaping optics are contained in the PDS tube assembly This assembly is an integral unit that allows the shaped laser beam to be pointed and steered without affecting the beam shape and collimation As shown in Figure 4 1 1 the shaped beam intersects the 90 PDS input mirror which directs it through the 90 PDS input window and into the sample volume The windows and mirrors mount on the optical block a key mechanical component of the instrument The optical block defines the physical location of the sample volume and serves as an int
42. never touch the end of the pin to any surface as it will deform 3 The probe must be operated in Live Video Mode to perform this procedure Live Video mode shows the full 1024 x 1024 CCD array 4 The full 1024 x 1024 pixels will not fit on the main operators window The horizontal dimension will fit but the vertical will not Figure 6 8 3 Figure 6 8 4 and Figure 6 8 5 show the full horizontal dimension of the array and the vertical scroll bar at the top bottom and center positions Notice that the corners of the array are clipped off by the imaging lens barrel This is normal 5 For this alignment procedure the goal is to center the camera on the point of the pin which has been manufactured to be in the center of the sample volume The vertical scroll bar must be positioned exactly in the center as shown in Figure 6 8 5 6 Insert the alignment pin into the optical block as shown in Figure 6 8 6 Be careful not to bump the point of the pin Insert the pin as far as it will go into the optical block Figure 6 8 7 At full insertion the pin will be very close to the center of the sample volume 7 Look at Live Video and you should see the pin as shown in Figure 6 8 8 Notice how the scattered light from the PDS 45 laser is visible Also notice that the pin is exactly in the center of the CCD array in this position 8 Using a ruler on the computer monitor locate the exact center of the CCD array and mark it with a piece of tape on t
43. of the probe s PDS system 5 3 4 Background Control Currently users set a time period in seconds after which the probe should take a background This is done so that variations in the image intensity over time can be removed when looking for particles in a captured frame An added feature that may be user enabled looks in every captured frame to see if multiple frames have captured a detectable ROI in the same area of the image So if for example a piece of dust on a lens were to remain in one spot this algorithm would then take a background thus removing the effect of the dust spot Otherwise every time a particle was detected by the PDS system causing the image processing software to look for ROIs the image processing would find the dust spot and count it as a particle Choosing the Settings Al Background Settings menu option brings up the form shown in Figure 5 3 3 The background adaptation just described is controlled in the lower half of the form and to cause the real time software not to perform the algorithm leave the Algorithm Enabled checkbox unchecked SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 114 SPEC CPI Preliminary Technical Manual Background Image Control and Adaptation Settings EJ Background Control Minimum Mean jo e 20 Maximum Mean li 80 Kaxinauire ROI fio size in Diff Image Maximum Time F010 Pulse Widt
44. out of focus number crystal type O circular 1 column 2 stellar 3 other Not used 0 ROI was drawn manually 15 Crystal type was manually corrected 15 Particle was manually rejected Scan List structure used to gather file info at load time Field Name BlockMark File postion ImgType int Image type 1 normal frame with roi s 2 background 0 error type 1 house keeping block SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice LLJ SPEC CPI Preliminary Technical Manual House Keeping time day byte Day From header unless HK then computed from S p o aS O enoa on hour byte Hour From header unless HK then computed from PS hame o a aan minute byte Minute From header unless HK then computed D a sec byte Sec From header unless HK then computed from Htime Mesec From header unless HK then 0 ROIsCount Number of ROPs in block 0 for HK blocks Size of House Keeping block or 0 if Image block SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 178
45. particle size approximately Trransit 0 5 x 10 3 meters V x Sin 45 Trransit 0 707 x 103 meters V SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice LO SPEC CPI Preliminary Technical Manual Where V is the velocity in meters per second To a first approximation the transit time including the particle size is given by Trransit 0 707 D x 103 meters V Where D Is the particle diameter in millimeters From this equation the transit time of a 10 micron particle traveling at 200 m S is 3 585 x 10 seconds The transit time counter operates at 48 MHz so this particle would have a total transit time count of approximately 172 counts A 200 micron particle at the same speed would have a transit time of 4 535 x 10 seconds and transit time count of approximately 218 In actuality the particle spends time in the beam during which the particle threshold is not exceeded so the transit time count is smaller than those given From this analysis it is apparent that a Minimum Transit Time setting of 200 when flying at 200 meters per second Is going to limit the smallest sizes seen in some cloud droplet distributions no particles might be imaged at all due to failing the minimum transit time criterion If the probe is not imaging particles adjust the raw value of the Minimum Transit Time Setpoint to 30 and click Apply in the Advanced
46. reaches its PDS light detector such that almost no light reaches the detector when no particle is present The diagram in the upper left of Figure 1 1 2 shows the laser beams being dumped in the absence of a particle in the sample volume The object plane for the imaging CCD camera is located on the trailing edge of the PDS beam intersection Upon instrument startup the imaging system pulses the imaging laser and captures a full frame background CCD image in the absence of cloud particles The background image is stored and used to SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 3 SPEC CPI Preliminary Technical Manual process subsequent frames thought to contain a particle The background CCD image is shown in Figure 1 1 2 When there is no particle flying through the instrument and only a small amount of light from the PDS laser beams hits the PDS detectors both detectors put out low voltage analog signals A typical low voltage analog signal is shown in red on the voltage waveform graph in Figure 1 1 2 An electronic comparator circuit on each PDS detector compares the detector output voltage with a PDS Threshold voltage The PDS threshold voltage is shown in blue If the PDS Detector output voltage never rises above the PDS Threshold voltage then no particle is detected and no firing of the imaging laser occurs The imaging CCD camera is constantly downloading i
47. sequence If you do not follow this sequence you may damage your CPI Warning The Data acquisition system and Sensor Power switch MUST be turned off before any cables are connected or Disconnected If you do not turn them off before connecting or disconnecting cables you may damage your CPI 2 2 1 Connection Procedure for Operating the CPI in the Laboratory 1 Verify that the Sensor Power Switch on the front of the Data Acquisition System is turned off Verify that the Data Acquisition System Computer is turned off see Figure 2 2 1 Front of the Data Acquisition System 2 Connect the Computer Power AC1 and AC2 power cables to a 115 Volt AC source The order of connection of the AC power cables is not important See Figure 2 2 2 CPI Cable Connection Diagram and Figure 2 2 3 Back of the Data Acquisition System 3 Connect the power dsp cable from J2 on the Data Acquisition System to J2 on the Sensor Head see Figure 2 2 2 CPI Cable Connection Diagram Figure 2 2 4 Connecting the power dsp to the Data Acquisition System and Figure 2 2 8 Connecting the power dsp cable to the Sensor Head 4 Connect the framegrabber cable from J1 on the Data Acquisition System to J1 on the Sensor Head See Figure 2 2 5 Connecting the framegrabber to the Data Acquisition System and Figure 2 2 9 Connecting the sensor camera cable to the Sensor Head 5 Connect the mouse keyboard monitor Computer Power AC1 and AC2 to the back of the Data Acqu
48. subtraction and performs a search algorithm to determine if a particle or particles is are present in the frame and cutting it them out into ROIs The parameters affecting this process are discussed in the next sections 5 1 4 1 Background Images and Parameters Two parameters define the recognition of a particle within a frame particle threshold and minimum size pixels The role of these parameters will first be discussed in explaining how a background image is taken SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 80 SPEC CPI Preliminary Technical Manual IMAGE 1 IMAGE 2 Figure 5 1 9 Representation of two 7 x 7 CCD camera images When the DAS is ready to take a background it waits until there are fewer than Strobes Threshold image frames per second that have an associated PDS STATUS bit high See Section 1 1 The PDS STATUS bit indicates the presence of sensed particles When there are fewer than Strobes Threshold image frames per second that have an associated PDS STATUS bit high a signal called EXTRIG from the frame grabber under DAS control is pulsed once per image frame period forcing the digital logic system on the sensor head to fire the imaging laser Two frames are thus generated a depiction of which is shown in Figure 5 1 9 The two image examples are only 7 x 7 pixels but the actual CCD camera sends over 1024 x 1024 pixel im
49. time and without notice 169 SPEC CPI Preliminary Technical Manual 7 3 2 Writes 1 House keeping control Write 0x2002 On a write data bus bits D 0 8 are latched into CTRL 0 8 in the DSP_HSKP logic CTRL 0 4 are clocked into TEMP _ADD_I 0 4 TEMP_ADD 0 2 TEMP_ADDI 0 2 CTRL 0 2 TEMP_ADD 0 2 are MUX selects on the relay board TSO TEMP_ADD_I 3 CTRL 3 TS1 TEMP_ADD_I 3 CTRL 3 TSO and TSI are MUX enables on the relay board CTRL 5 8 are clocked into CC 0 3 the house keeping state machine down counter 2 System Control Register Write 0x2004 Data bus bit D 1 is inverted and latched with the latch output driving the watchdog IC the MAX6823 The DSP should write to this address toggling the value on D 1 on each write 3 Laser Pulse Timer Write 0x2005 A write to this address latches data bus bits D 0 12 If D 11 1 a timer counts down from the value latched off of D 0 10 at 48 MHz firing the laser after the count reaches 0 in the presence of a particle This allows programmable delay for firing the laser and should come from the data system Writing a O to bit D 11 disables this feature If D 12 1 the PDS state machine goes into diagnostic mode FORCE_TRIG in the NewStateMachine ppt slide 4 This bit should be a O in regular operation and should be controlled by the data system 4 General Purpose Latch Write 0x2006 A 9 bit general purpose register that latches data bus D 0 8 to GP 0 8 i
50. together by one temperature sensor mounted in the base near one of the slug heaters The pylon base patch heater and pylon cover patch heater are shown in Figure 3 1 6 Each of these heaters has its own temperature sensor and they are individually controlled in the software The main purpose of the pylon heaters is to de ice the pylon when flown in icing conditions During normal operation these temperature zones should not fall below freezing in icing conditions In very cold temperatures such as 60C these temperatures may fall below freezing but icing is not a concern at these temperatures SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice os SPEC CPI Preliminary Technical Manual PYLON SLUG HEATERS AND SENSOR PYLON SLUG HEATERS g PYLON BASE PATCH HEATER AND SENSOR Figure 3 1 6 Photograph showing location of pylon heaters APD HEATER AND SENSOR CENTRAL SAMPLE TUBE A ae HEATER AND SENSOR 5 S e IMAGING LENS HEATER AND SENSOR SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 34 SPEC CPI Preliminary Technical Manual Figure 3 1 7 Photograph of heat zone locations on front side of internal sensor amp E PDS 45 sas HEATER AND SENSOR i gt gt lt g al z nt IMAGE LASER We HEATER
51. 3 1 Settings Menu Al Items Figure 5 3 1 shows the Settings menu options The Settings SPP100 Settings and Settings Single Board Computer Settings options should be ignored as they are features of a purely stand alone data system or a system incorporating an SPP100 instrument The two menu options that change the control algorithm SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 110 SPEC CPI Preliminary Technical Manual behaviors including turning them on and off are Settings Al Background Setting and Settings Al PDS Control Settings These will be discussed in the following sections te Data File E 06041007_101 RECORDING DISABLED Time 6 4 11 56 6 File View Bt Commands Window Help Probe and Display ee Advanced Control and Settings Ip Al Background Settings Al POS Control Settings SPP100 Settings Single Board Computer Settings FF223 0 0 FF230 0 0 foc bre cho reared Lp rot Fs FF231 0 0 rare Lp Porat Figure 5 3 1 The New Settings Menu 5 3 2 PDS Laser Control The CPI due to changes in temperature affecting optical paths and laser power fluctuations requires monitoring and control of the PDS laser settings Users typically set the laser power monitoring the PDS DC voltage on both the PDS45 and PDS 90 lasers attempting to set the PDS laser power as high as possible without going over 8 8V on the monitor The ar
52. 43 is the image lens temperture ad590 243 Gain Offset43 0 029356 1 877500 10 000000 30 000000 244 245 7G 044 is thelaser trigger timer thresh 246 Gain Offset44 20 83e 9 0 000000 0 000000 2 3e 6 247 Display Options 248 ROI DX 132 249 ROI DY 0 ZOO ROI Columns 5 29d ROI Rows 4 252 Pixel Size um 2 3 LIS Flags 32790 254 Display Frame Skips 0 TEOR Histogram Bins 20 ZNO Histogram Min Size 0 ATIG Histogram Max Size 109 25O Histogram ITime 10000 ZOO Histogram Refresh 1000 260 Rates ITime 3000 261 Air Speed m s 150 2O ROI XY Plot Max ROIs 1000 ZO oi ROI XY Plot Reset When Filled 1 264 Serial Data Parameters 263 5 PortSettings COM1 baud 9600 parity N data 8 stop 1 ZOOS BlockSize 72 ZOS BLOCKOIZO TEO 268 BlockMark r 269 NumFields 30 ZT Fieldl Hour 02d TA See Field2 Minute 02d ZZ Field3 Second 02d Dhan Field4 Pressure mb 6 1f 2 as Field5 Temperature C 6 1f CE Fieldo Relative Humidity 5 1f SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 166 SPEC CPI Preliminary Technical Manual 276 Field7 Wind Speed m s 5 2f 2A Ea Field8 Wind Direction degree magnetic 5 1f DAS Field9 Latitude deg 11 7f 279 Field10 Logitude deg 12 7f 280 Fieldll Altitude m 7 1f ZB eg Field1l2 East Velocity m s 6 1f DOP Field13 North Velocity m s 6 1f 2B F
53. 45 laser collides with the pylon screw boss damage to the laser can occur Study Figures 6 3 18 through Figure 6 3 22 before proceeding further Place your hands in the position shown in Figure 6 3 18 with the left hand on the green handle and the right hand as shown Continue to slide the internal sensor in the direction shown in Figure 6 3 18 Eventually the internal sensor will be completely freed from the pylon spreader grommet Figure 6 3 19 and the inlet adapter Figure 6 3 20 As shown in Figure 6 3 20 rotate the bottom of the internal sensor upward pivoting around the laser guard and taking great care to safeguard the PDS 45 laser After the PDS 45 laser and pylon spreader are cleared Figure 6 3 21 lift the internal sensor upward out of the pylon Place the internal sensor on the side shown on an ESD safe surface Figure 6 3 22 The internal sensor should rest on the support feet Figure 6 3 23 to protect sensitive components from misalignment or damage SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 126 SPEC CPI Preliminary Technical Manual SLIDES BACK FOR SENSOR INLET ADAPTER REMOVAL FORWARD FOR FIXED MOUNT POINT INSTALLATION O SCS ES x PYLON SPREADER FIXED MOUNT POINT PYLON CONNECTORS CAPTIVE TO PYLON Figure 6 3 2 B a A PREVIOUSLY DISCONNECTED CAMERA CONNECTOR N jo SMALL FLAT
54. 90 laser power 10 PDS 45 detector DC level 11 PDS 90 detector DC level 12 PDS 45 threshold Voltage 13 PDS 90 threshold Voltage 14 PDS minimum transit time Items 1 through 4 are easily accessed via the Lasers tab of the Settings window of Figure 5 2 6 Items 5 through 7 are easily accessed via the Probe tab of the Settings window shown in Figure 5 2 3 SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice Od SPEC CPI Preliminary Technical Manual No Did probe initialize Correctly See flowchart in Figure 5 2 1 Yes No Background Valid Enunciator present See flowchart Yes in Figure 5 2 2 Are PDS DC Yoltages greater than 8 8 less than 3 5 Yes See PDS section 5 2 4 1 and No adjust laser power Are PDS threshold settings greater than 600 less than 200 Yes See PDS section 5 2 4 2 and adjust threshold Yes Is the PDS minimum transit Time greater than 30 less than 20 See PDS section 5 2 4 3 and adjust minimum transit timer Enjoy the flight your probe is working Figure 5 2 7 PDS troubleshooting flowchart SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 108 SPEC CPI Preliminary Technical Manual 5 2 4 1 What To Do If PDS Laser Power Needs Adjustment The indic
55. 95 Pee 469 046 950945 T LIRAS Ter tT 34 38 a sM d 134 90 I Ties Per eee N 35 rs ikon ee ber ji ates aul bnagr Pee tenatt irre LoP OL 9E b26 St 92 959 L gt 97 96 Lp 9E Pstact JED Booto rate nozin A ve video rp bmp pant JUEK Figure 6 8 11 Figure 6 8 12 SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 158 SPEC CPI Preliminary Technical Manual 7 0 APPENDICES 7 14 Mechanical Drawing for Installation On Aircraft 2 5 2 2 EXTERNAL DIMENSIONS SAMPLE CUT AWAY VIEW MOUNT HOLES 7 Pene Ske ee SPECHING 7X 1 4 28 12X 8 32 er pseu EO ArII I Aa EAA ST 2d 1 LAA ee 4 roids CPIVERSION 2 paran CHV HOE ae OVERALL DIMENS IONS nw Ass SEE DWC HO FEN Hiha C soc OK ACC AN PT al 0 SCAIESIID WEI SHEELI Get 2 3 2 Figure 7 1 1 CPI External Dimensions SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 159 SPEC CPI Preliminary Technical Manual 12X 8 32 FASTENERS THROUGH MOUNTING PLATE INTERFACE 7X 1 4 26 FASTENERS THROUGH MIN THREAD ENGAGEMENT APP 0 925 MOUNTING PLATE INTERFACE j MAX THREAD ENGAGEMENT APP 0 500 MIN THREAD ENGAGEMENT APP 0 375 MAX THREAD ENGAGEMENT APP 0 500 CUT OUT IN MOUNTING PLATE TO ALLOW CONNECTOR CLEARANCE 2 188 c in Ei H Hi EEF vila gt oV 3X 1 500 A
56. Actual Laser Power Actual Actual LEVEL Laser Power Setpoin ion mi WELL BELOW 8 8 Y PDS 90 elector DC Level 6 9012 V LASER SET POINTS Laser Power Actual 39 823 mw AT FULL POWER Laser Power Setpoin mw IMAGING ponon 140 Laser Curent Actual 33 5103 V 34 8638 V ser Curent Setpoint 33 4960 y Figure 6 7 10 6 8 CPI Imaging System Camera Alignment The CPI imaging system camera may need to be realigned if the imaging system goes out of alignment over repeated airborne operation or it is removed from the instrument for servicing This procedure provides a fundamental overview for aligning and focusing the imaging system camera and lens assembly CAUTION The overall quality of the images recorded by the CPI depends on the camera being properly aligned and focused The alignment procedure should only be performed by personnel who have read and become familiar with this procedure 1 An alignment pin is included with the CPI for use in centering and aligning the imaging system Figure 6 8 1 2 Figure 6 8 2 shows the proper way to remove the cover from the alignment pin The pin has been machined on a lathe to come to a sharp point at an exact distance into the optical block Be SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 151 SPEC CPI Preliminary Technical Manual careful not to damage the pin during handling and
57. B P 1 5 mm F 25 mm F 25 mm F 30 mM DIAMETER rato NM gamm ACTIVE BEAM BLOCK pei Figure 4 1 3 Ray trace for 90 PDS collection optics a beam in X Z plane b beam in Y Z plane c scattered light path X Z plane d scattered light path Y Z plane Figure 4 1 4 is a solid model showing all of the components for the 45 PDS collection system The 45 PDS laser and beam shaping optics are identical to the 90 PDS laser and beam shaping optics described above The primary difference between the 90 PDS and 45 PDS optical systems are found in the collection optics The collection lenses must have longer focal lengths because the distance from the first collection lens to the sample volume is longer due to the beam crossing the sample tube at a 45 angle SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 40 SPEC CPI Preliminary Technical Manual MIRROR PDS PDS CYLINDRICAL CYLINDRICAL LENS1 LENS2 NARROW 45 PDS COLLIMATING MASK INPUT 45 PDS ____ INPUT SAMPLE WINDOW VOLUME 45 PDS OUTPUT ha WINDOW 45 PDS tan al COLLECT1 45 PDS COLLECT2 nil DUMP a 45 PDS 45APD SPOT OUTPUT 45 PDS FOCUSING WINDOW MIRROR DETECTOR LENS Figure 4 1 4 45 PDS system optical component layout Figures 4 1 5a d are ray traces for the 45 PDS collection optics The lenses labeled 45 Collection Lens1 and 45 Collection
58. Camera Image Processing A digital logic state machine inside U20 processes the PDS 45 pulse from U18 and the PDS 90 pulse from U26 and decides when an imaging laser strobe can occur The PDS 45and PDS 90 pulses are digital logic 3 3V CMOS compatible signals They are fed into U20 a CPLD logic chip that controls the firing of the imaging laser U20 also provides interrupts and data to the DSP U35 and an output signal providing status of the current image being sampled by the Basler A501 camera A timing diagram of the relevant signals for particle imaging is shown in Figure 4 2 3 EXSYNC DATA FLASH PDS 45 amp PDS90 PIB OK LSR TRIG Uo Os PDS STATUS mae STATS BASLER A501B UAV CPI Camera Timing With PDS STATUS EXSYNC EDGE CONTROLLED SEE A500 MANUAL SECTION 3 3 1 1 Figure 4 2 3 Particle imaging timing diagram SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice ol SPEC CPI Preliminary Technical Manual 4 2 2 1 Logical State Machine The PDS detection system is managed by a logical state machine located inside the Programmable Logic Device PLD U20 A diagram of the state machine is shown in Figure 4 2 4 The state machine idles in state 0 S0 As long as there is no particle seen by the PDS 45 and PDS 90 detectors it idles in SO and S8 The EXSYNCIN pulses from the frame grabber have no effect on it other than to driv
59. Control and Settings window shown in Figure 5 1 6 in the Software Description Section 5 1 5 2 5 Enunciator Warnings When operating with no limits exceeded such as heat zone measured temperatures laser powers etc the DAS enunciator panel see the upper part of the window shown in Figure 5 1 1 in the Software Description Section 5 1 should have one green background alert stating Background Valid Any other alert given in red yellow or blue indicates a parameter is out of the assigned operating range Users assign these limits in the cpi INI file described in Section 5 1 7 The enunciator panel is further described there as well If any alerts other than Background Valid or short alerts titled Getting Background are in the enunciator panel read Section 5 1 7 and address the problem 5 3 Artificial Intelligence Al DAS Controls Incorporated into the software are control algorithms that automate the PDS threshold settings the PDS laser power settings and the imaging laser power Also available for use is an algorithm to take a new background any time a particle is seen in nearly the same position in multiple frames All of these algorithms were designed to remove the need for an operator to monitor and control the system settings However this should not preclude operator oversight and we encourage users to turn the control algorithms off until they have spent significant lab time familiarizing themselves with them 5
60. E NEW IMAGE Figure 5 1 12 Background image and new CCD camera image for particle extraction example SUBTRACTION RESULT Figure 5 1 13 Result of background subtraction on images of Figure 5 1 12 The DAS looks through the background subtracted image and compares the values such as those shown in Figure 5 1 13 with the particle threshold parameter With the particle threshold at 40 only four pixels in the image are considered as shadowed due to a particle If the particle threshold were lowered to 38 the DAS would recognize eight shadowed pixels The number of collocated SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 84 SPEC CPI Preliminary Technical Manual pixels is then compared to the minimum pixel size parameter The value of four for this parameter means that this particle is accepted as an ROI and stored if recording is enabled to the current data file Other parameters under user control affect how a recognized ROI is stored The ROI X Pad and ROI Y Pad fields both set to 6 in Figure 5 1 11 tell the DAS to include six pixels to the left and right and six pixels above and below a rectangle that encompasses all recognized shadow pixels as described in the previous paragraph when saving the ROI image to file 9 1 4 3 Image and Background Mean Settings Because the CCD camera s active area is unlit except by the flash of the ima
61. EC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice LOZ SPEC CPI Preliminary Technical Manual 13 When the focus is optimized tighten the lock screws and replace the aluminum tape 14 Now insert the pin back into the optical block at the full insertion depth and turn off the PDS lasers If the pin is still in the center but not in focus slide the pin out of the optical block slightly until the best focus is achieved You should not have to move the pin very much to find the best focus 15 Most likely the pin will now be in focus slightly off the vertical centerline Now readjust the image mirror tilt screws to place the pin in the horizontal center of the array The pin should still be in focus Now tighten down the image mirror lock screw Figure 6 8 9 16 Turn the PDS lasers back on and the PDS 45 laser should end up at the end of the pin looking very similar to Figure 6 8 8 By adjusting the focus while pulling drops through the probe the focus is set to the trailing edge of the PDS beams where the image laser is set to trigger Adjusting the tilt of the imaging mirror slightly relocated the center of the sample volume to optimize the focus and particle detection 17 The alignment and focusing procedure is now complete Figure 6 8 1 Figure 6 8 2 SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any ti
62. Figure 6 5 8 SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 138 SPEC CPI Preliminary Technical Manual HOLD INTERNAL INSTALLATION SENSOR DIRECTION AS SHOWN INSTALLATION DIRECTION GAP DECREASES ra BETWEEN PYLON CONTINUE TO SPREADER AND SLIDE INTERNAL INTERNAL SENSOR SENSOR ONTO AS SENSOR SLIDES INLET ADAPTER ONTO GROMMET AND PYLON PYLON SPREADER SPREADER Figure 6 5 9 Figure 6 5 10 LIFT UPWARD ON GREEN HANDLE SLIGHTLY TO PUSH TOWARD FRONT OF PYLON WITH FORK T ALIGN AFT SAMPLE TUBE er N AS IT CLEARS MOUNT BASE PUSH DIRECTION di PUSH ON GREEN te HANDLE WITH HAND p to l N ee Pai LIFT TUBE UPWARD ae eS N ALIGN AFT SAMPLE TUBE SLIGHTLY TO CLEAR ALIGN FORK WITH AFT N WITH SENSOR BY HAND MOUNT BASE TUBE AND PYLON BOSSES a JI i Figure 6 5 11 Figure 6 5 12 MOUNT BASE HOLES ALIGN WITH AFT TUBE HOLES Sa 8 32 TORX af iy PLUS FASTENER oe PYLON SPREADER POSITION RELATIVE TO INTERNAL SENSOR IN FINAL POSITION j J JR gt i i Figure 6 5 13 Figure 6 5 14 SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 139 SPEC CPI Preliminary Technical Manual e TORX PLUS FASTENERS FULLY TIGHTENED Figure 6 5 15 Figure 6
63. G TOOL WITH ROUNDED _ EDGES PROVIDED 2 4 Oy i A ee e i S va t Figure 6 7 2 Figure 6 7 3 SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 148 SPEC CPI Preliminary Technical Manual Figure 6 7 4 Figure 6 7 5 PDS 45 INPUT WINDOW PDS 45 LASER BEAM IMAGE LASER INPUT WINDOW 7 LLLLLLLLALLLAL A Zk al SIDE SAMPLE VOLUME pas SECTION a VIEW Clk ous a a m AA KULLLKI A Pa IMAGE LASER BEAM OPTICAL BLOCK m PDS 90 INPUT WINDOW 7 VM WA VA TOP oa 77 WANE VIEW AIR css ala wea LLLLZ LL A aaa FLOW A A eo PDS 90 OUTPUT WINDOW PDS 90 LASER BEAM Figure 6 7 6 Cutaway of optical block showing laser beam locations and window locations SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 149 SPEC CPI Preliminary Technical Manual _ WETTED COTTON SWAB PDS 45 OUTPUT WINDOW CPI CLEANING TOOL IMAGE OUTPUT WINDOW PDS 45 INPUT WINDOW IMAGING INPUT WINDOW a M Figure 6 7 9 SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 150 SPEC CPI Preliminary Technical Manual Ci x Probe Disp Hist Plots Lasers i PDS Ez Detector DC Level 7093 PDS 45 AND 90 DC ee Laser Power
64. L SENSOR SLIDES OFF PYLON SPREADER AND INLET ADAPTER A INLET ADAPTER O RING EXPOSED AS INTERNAL SENSOR SLIDES BACK Figure 6 3 14 AFT SAMPLE TUBE FINAL POSITION WHEN BOTH O RINGS ARE EXPOSED REMOVE AFT SAMPLE TUBE BY HAND FROM INTERNAL SENSOR Figure 6 3 16 SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 129 SPEC CPI Preliminary Technical Manual DELRIN LASER REMOVAL GUARD 3 CAUTION 45 DIRECTION PDS LASER T Eg PTD HOLD INTERNAL SENSOR AS SHOWN mi CONTINUE TO SLIDE INTERNAL a T SENSOR FROM i Q Vv INLET ADAPTER lela O AND PYLON u hd Bea SPREADER Figure 6 3 18 PYLON SCREW BOSS 1 PIVOT AROUND INTERNAL SENSOR LASER GUARD WILL BE COMPLETELY FREED FROM GROMMET a x _ DO NOT BUMP 45 PDS LASER ALIGNMENT MAY BE AFFECTED INTERNAL SENSOR EON GHSERGEE ROTATE WILL BE COMPLETELY BOTTOM OF FREED FROM INLET WITH GROMMET SENSOR AROUND LASER GUARD ADAPTER 1 2 WEE all Figure 6 3 19 Figure 6 3 20 PLACE INTERNAL SENSOR ON AN ESD SURFACE AS r E N 1 SHOWN Figure 6 3 21 Figure 6 3 22 AFTER 45 PDS LASER AND PYLON 1 SPREADER ARE COMPLETELY CLEARED LIFT INTERNAL SENSOR UPWARD SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and with
65. Lens2 have longer focal lengths than the corresponding lenses in the 90 PDS collection optics Relay lenses are not necessary due to the shorter path length to accommodate the mechanical packaging As in the case of the 90 PDS collection optics 45 PDS Collection Lens2 is the limiting aperture that defines the maximum collection angle of 8 2 SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 41 SPEC CPI Preliminary Technical Manual 45 PDS COLLECTION SAMPLE 14 45 APD 45 PDS VOLUME 45 PDS DUMP FOCUSING DETECTOR COLLECTION SPOT LENS L2 LASER ht E PATH a X Z PLANE LASER BEAM m i i b PATH Y ZPLANE 79 23 48 3 94 5 10 4 ELEMENT SPACING IN mm SCATTERED E LIGHT pn En Eg i PATH Se i c X Z PLANE SCATTERED i LIGHT eE z zE i PATH SS o i d Y Z PLANE S F 60 mm 2 5 mm X 1 5 mm F 50 mm 0 5 mm F 30 mm DIAMETER BEAM BLOCK ACTIVE AREA Figure 4 1 5 Ray trace for 45 PDS collection optics 4 1 2 Imaging System Figure 4 1 6 is a solid model of the CPI imaging optical system showing all of the components The two primary components of the system are the imaging laser and the imaging system lens The primary function of the imaging system is to capture images of cloud particles as they move through sample volume at aircraft speeds This is accomplished by flashing a laser at pulse widths up to 40 ns whil
66. MAGE 1 and the computer should therefore look at IMAGE 2 which Is transferred due to EXSYNC2 The computer will during EXSYNC2 look at the new PDS STATUS signal The blue timing line represents when the computer looks at this signal It is sent from U20 on the DSP board to the frame grabber It tells the data acquisition system to process the next image received During FRAME INTERRUPT 2 the data acquisition system will therefore process the next image received SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice oe SPEC CPI Preliminary Technical Manual PIB OK FORCE ppgy ALL OTHERS CLR_TT EN_DT IPDS_STAT_OUT IEXSYNCIN IEXT_TRIG iEN_GPC Ky PDS_STAT_OUT PIB_OK IEXSYNCIN ALL OTHERS ICLR_TT CLRX CLR_SMPL CLR_SMPL EN_DT ALL OTHERS fEN_GPC IPIB_OK TRIGSET PDS_STAT_OUT CLR_SMPL LSR_TRIG EXSYNCIN ARM LASER PDS_STAT_OUT LASER_OFF PDS_STAT_OUT CLRX IPDS_STAT_OUT HOLD N Precedence of operators Before before 4 EXSYNC SW1 56 57 S0 51 52 83 PDS45 PDS90 ie IN SW2 S0 PDS45 PDS90 PIB 51 52 83 84 85 g CLRX MASERA RT See ae ree XL IPIB_OK FORCE_PDS PK_SLS EN_PK_45 CLR_SMPL S0 PDS_45 EN_PK_90 CLR_SMPL 0 PDS_90 PDS STATE MACHINE Figure 4 2 4 PDS State Machine 4 2 3 PDS 45 PDS 90 amp Imaging Laser Drivers These analog processing electronics cons
67. MIRROR IMAGE SYSTEM LENS CAMERA Figure 4 1 6 Imaging system optical component layout The collimated beam is directed into the sample volume using the image laser input mirror After passing through the sample volume the beam passes through a correction plate before being folded into the imaging system lens The laser provides the illumination to image particles as they pass through the sample volume In the absence of a particle the imaging laser must provide a uniform and repeatable background on the CCD camera The imaging system lens expands the incoming laser beam by 5X magnification to uniformly illuminate the CCD chip SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 43 SPEC CPI Preliminary Technical Manual The CPI uses an imaging lens with a primary magnification of 5X A feature of the imaging lens is the ability to maintain a constant magnification over its focus adjustment range The focus of the imaging system is adjusted with an adjustment barrel on the body of the lens This lens system greatly simplifies the optical alignment of the imaging system The correction plate is necessary to correct the astigmatism produced in the imaging system This astigmatism is the result of the image output window being tilted at an angle of 45 to the imaging system optical axis The rays are refracted at different angles depending on where they intersect t
68. Offset30 0 000610352 0 000000 0 000000 60 000000 G O31 is the PDS90 Laser Power Set Point Gain Offset31 0 0096665 0 754 12 000000 43 000000 G Os2 as the PDS90 Threshold Set Point Gain Offset32 0 000610352 0 000000 0 000000 40 000000 G 033 is the Imaging Laser Current Set Point Gain Offset33 0 0085449 0 000000 0 000000 35 G O34 is the Imaging Laser Pulse Width Set Point Gain Offset34 0 009353 0 000000 0 000000 38 G 035 is the Minimum Transit Time Set Point Gain Ofisel 35 20 833336 9 0 000000 0 000000 10007000000 Dead Time Garn7OrEeset3o 1 0 02000000 Gz000000 Q Rev3l only e 7 SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice EOS SPEC CPI Preliminary Technical Manual 22 4 G O37 is the APD90 Amplifier Temp From Where PEO Gain Offset37 0 029356 1 877500 10 000000 35 000000 22O L224 3 G O38 is the Vref10 Voltage From Where 228 Gain Offset38 0 001464843 0 000000 1 000000 35 000000 Pais ZS Og G 039 is the Pressure Sensor 2AM Gain Offset39 0 011014 3 7594 0 000000 35 000000 ZS A 233 G O40 is the SLS laser power setpoint mw 234 Gain Offset40 0 007324219 0 000000 0 000000 0 600000 2 2364 G O39 is the PMT voltage 23l Gain Offset41l 0 007324219 0 000000 0 000000 0 400000 238 F 23 G O042 is the pylon cover patch therm 240 Gain Offset42 0 013736 21 7308 0 000000 35 000000 241 242 G 0
69. PDS 45 and PDS 90 The PDS 45 laser power set point is controlled using the slider bar shown in Figure 5 1 7 with value 2123 As the slider is adjusted the raw number is incremented and decremented This value is a set point sent to the sensor head DSP board See Section 3 Figure 3 1 5 which applies this value to a digital to analog converter DAC with its output setting the desired PDS 45 laser power The laser power set point is given in units of milliWatts mW and is updated as the slider is moved SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice T SPEC CPI Preliminary Technical Manual Settings es POS 45 Detector OC Level 4 2185 Laser Power Actual 20 185 mie Laser Power Setpoint po Bel mat 2125 j POS 30 p etector OC Level 5 2780 W Laser Power Actual 26 297 reve zeng Laser Power Setpoint a mA Laser Curent Actual 33 0591 Y Pulse width Actual 22 9560 Vv Laser Current Setpoint 33 051 ty 2868 E Puke Width Setpoint 22 6997 W 2427 APPLY RESET Figure 5 1 7 Lasers tab of the Settings window Once the desired set point is chosen with the slider the user must click the APPLY button for the new setting to be sent to the sensor head If APPLY is not clicked any changes to the settings in this window will not be implemented on the sensor head The detector DC level has unit
70. PI EXHAUST TUBE Figure 2 3 3 Figure 2 3 4 SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 20 SPEC CPI Preliminary Technical Manual ee UE Figure 2 3 5 Figure 2 3 6 2 4 CPI Startup Procedure 1 Verify that all cables are connected according to the Connecting CPI Sensor Head to Data Acquisition System Section 2 2 See Figure 2 4 1 SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice Al SPEC CPI Preliminary Technical Manual Figure 2 4 1 Rear of Data Acquisition System with all cables connected 2 Unlock amp open the disk drive bay door 3 Start the Data Acquisition System computer by pressing the Computer Power switch on the lower left side of the disk drive bay by the red RESET button See Figure 2 4 2 Allow the computer to boot up ud Particle Imager Bren eee GPEC iw fo sd Pas g P r P L 7 D P SS asdf ty ee yi e 5 oo AR l Je oy i Po we p lt tet adi E B E _ lt j p Figure 2 4 2 Front panel of the CPI Data Acquisition System 4 Double click the CPI icon on the desktop to start the CPl exe program J After the CPI program has started switch on the Sensor Power switch on the front panel of the Data Acquisition System See Figure 2 4 2 6 single click the Start Probe button on the
71. Pylon Cover Patch Bit 9 gt Pylon Slug Bit 10 gt Pylon Base Patch Bit 11 gt Imaging Laser Bit 12 gt PDS 45 Laser Bit 13 gt PDS 90 Laser Bit 14 gt Spare _DC1 Bit 15 gt Camera il 6 Forward Sample Tube Temperature Setpoint 1 8775 0 02935559 1 8775 0 02935559 8 Lower Optics Block Temperature Set Point 1 8775 0 02935559 9 Central Sample Tube Temperature Set Point 1 8775 0 02935559 1 8775 0 02935559 1 8775 0 02935559 1 8775 0 02935559 1 8775 0 02935559 0 02935559 0146484 0146484 0146484 0146484 19 PDS_45 Laser Power Set Point O CS 0 0073982 20 PDS_90 Laser Power Set Point O 0 0073982 21 PDS_45 Threshold Set Point O 0 00061035 22 PDS_90 Threshold Set Point O 0 00061035 23 Imaging Laser Current Voltage O 0 00642700 24 Imaging Laser Pulse Width Voltage O 0 007995605 25 Minimum Transit Time _ O 20 83e 9 26 Heater Status 2 Bit Mapped 1 on 1 i ii Bit 1 gt SLS Laser 90 APD Amplifier Temperature Set Point Unused 0 02935559 SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 6 SPEC CPI Preliminary Technical Manual Imaging Lens Set Point 1 8775 0 02935559 35 Laser Trigger Time Threshold Bits 0 10 gt Count at which to fire needs to be 20 83e 9 greater than the minimum transit time above The temperature set points are integers in the range of 2048 t
72. RR PDS data block 3 Anva 0 __ Amivalime 7S AnivalT2_ 0_ Amivaltime 2 SOS TransitT 0 Tiie Missed Jo number of particles missed while processor is busy pHi oo oo SOSO PHeight2 O Note header file only has one of these listed PDSChkSum 0 _ ehecksum OOOO ProbeMode 0 _ probemode SSCS Image header Data contained in the raw ROI file from the instrument Field Name BlockMark sO Block mark ROIInfoSize Total bytes in this block variable because of the last two fields Tracks this structures version ROIVer oO sx 0 Start X upper left corner of roi relative to CCD frame SX Start Y upper left corner of roi relative to CCD frame SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 174 SPEC CPI Preliminary Technical Manual rex 0 Ena X upper let comer of roi Creative to CCD frame rey _ End upper left comer of roi relative to CCD frame PixByies 0 Bytes per pixelinimage Flags 0 Contains info about particle see definition below Ten 00 Computed Length of particles majoraxis Wid 0 0 Computed wid of particle perpendicular nat vio Dak 0 Info on particle depth and cut off See definition Below ROI image data follows each image header The min file leaves this data out SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and withou
73. Technical Manual PDS 45 INPUT WINDOW IMAGE LASER INPUT MA PDS 45 LASER BEAM SIDE SECTION VIEW TI RERA TOP SECTION VIEW AIR Soak FLOW een Cm A PDS 90 OUTPUT WINDOW PDS 90 LASER BEAM Figure 3 1 4 Cutaway of optical block showing laser beam locations and window locations Figure 3 1 5 is a photograph showing the location of the electronics printed circuit boards in the CPI sensor head The power supply board and Digital Signal Processor DSP control board are equipped with temperature sensors that monitor the temperature of these boards This information is displayed in the housekeeping window These temperatures are monitored but do not have a corresponding temperature setpoint in the advanced control and settings window as there are no heaters associated with these circuit boards SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 32 SPEC CPI Preliminary Technical Manual DSP CONTROL BOARD Figure 3 1 5 Photograph showing location of the CPI printed circuit boards Figure 3 1 6 is a photograph of the pylon cover and pylon main body showing the location of the different heat zones The heat zones in the pylon are broken into three different areas for control the pylon slugs pylon base patch and pylon cover patch Physically there are four pylon slug heaters two in the pylon cover and two in the pylon base They are all controlled
74. ace in both the rack mount computer case and the sensor head PDS 90 PDS 45 Laser Laser Data Acquisition system i o PC Camilink f Frame Grabber RS 422 Serial Port Removable Hard Drive Data acquisition Computer Photo Detectorst Digital Signal Processor Board EXSYNC Serial Data N D Analog lJ T Relay Board Data JS 3 J 2 28 VDC po Power Board J Ga i 115VAC De ice Sensor Head 115 VAC Power Input LJ CPI Rieck Diagram SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 1 SPEC CPI Preliminary Technical Manual Figure 1 1 1 CPI Block Diagram 1 1 2 Functional Overview IMAGING LASER PDS 45 LASER i PDS 90 hjg n cuTaway LASER __AIR FLOW SAMPLE qa 1024x 1024 Pixels TUBE N 90 PDS DETECTOR VWIRROR 45PDS f DETECTOR IMAGING LENS Background with No Particle P CAMERA SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 2 SPEC CPI Preliminary Technical Manual n Waveforms of PDS Detectors No Particle olls PDS Threshold PDS Detector Output eee a Output of Detector Circuit Time Figure 1 1 2 Optics PDS detector waveforms and exposed image of the CCD camera when no particle is present In the CPI a two beam particle detection system strobes a high power
75. ad E f No Image Display AOI Y Pad E Raw Images Full Background Subtracted _ Rej Fme Background Images Frm Generate PDS Triggers Display Image Information ROI Rejection Criteria For Each Image Pre Set Rls Debug Periodic Statistics Min Size Pixels a Background Options Fill Ratio 7 be 0U6 il Ratio Update Background Now 640 2 Aspect Ratio gt 1 Bkground Rate secs e0 Min Img Mean Max PDS Aate 10 Figure 5 1 11 Image processing control section of the Advanced Control and Settings window Max Img Mean 5 1 4 2 Particle Collection and Associated Controls The process of searching for particles in an image frame that arrives with a concurrent PDS STATUS bit value of one indicating the imaging laser was fired due to the presence of a particle is much like the process for acquiring a background image The new image is subtracted from the background image and the difference image referred to as a background subtracted image is searched for pixels below the particle threshold An example of the background image IMAGE 1 SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 83 SPEC CPI Preliminary Technical Manual taken from Figure 5 1 9 and an image with a potential particle are shown in Figure 5 1 12 Figure 5 1 13 shows the background subtracted image BACKGROUND IMAG
76. ages though the camera is capable of 1280 x 1024 To check for a valid background image the camera will use IMAGE 1 as the background if the process qualifies it the DAS performs a bit by bit subtraction of the two images The result is shown in Figure 5 1 10 SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 81 SPEC CPI Preliminary Technical Manual SUBTRACTION RESULT Figure 5 1 10 Result of background subtraction applied to images of Figure 5 1 9 The DAS now checks each pixel value in the subtracted image to see if it is greater than the current Particle Threshold value divided by three backgrounds are more strictly tested than when testing for particles described later Thus if the particle threshold were set to 15 by the user the corner pixels with value of 5 would meet or exceed the 15 3 5 threshold used for backgrounds In that case the DAS would check to see if there are equal to or greater than the Minimum Pixel Size number of pixels collocated that meet or exceed the pixel threshold just described If the minimum pixel size were set to three then the above attempt at a background would fail In that case the DAS would generate two more EXTRIG signals and perform the background test algorithm just described on two new images However if either the particle threshold were raised to 16 or greater or the minimum pixel size were rai
77. alConstruct Enabled 1 Level 9 ThrowError CUserConfigCamera FinalConstruct No cameras are specified in the registry CMemoryOperator FinalConstruct CMemoryOperator FinalConstruct m_bDontLockLargeMem 0 ThrowError CBlobOperator FinalConstruct Operator is NOT licensed The final line indicates Operator is NOT licensed meaning the software could not find the hardware key see Figure 2 2 3 of the Connecting the CPI Sensor Head to the Data Acquisition System Section 2 2 Locate and plug in the hardware key SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 100 SPEC CPI Preliminary Technical Manual 9 2 2 3 Imaging Laser Power Too Low or Too High The probe won t acquire a background if the image mean is too low or too high A possibility is that the imaging laser power has been turned down or up in the controls such that the incident light energy is not within operating range on the CCD camera If this is the case the rtialog txt file will have text like the following in it CSerialComm ReadDataPacket a PDS packet received Cnt 2764 PCLNKCapture 0 Frm 2831 1 0 2 2 0 0 2 XFer 0 0086 s Period 0 0136 s CCorecoPCLNKDevice CompleteAcquire m_bFrameCycleComplete CBlobOperator PerformOperation Mean 0 000336sec frame Mean 9 75 CBlobOperator PerformOperation BAD Mean 9 Valid 63 195 The last line tells the u
78. along with the DAS time On the right side of this line are the standard window controls Hide Minimize Maximize and Close The next line contains the menu items File View Settings Commands Window and Help SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice G3 SPEC CPI Preliminary Technical Manual atiro Deicecn r pose setts Pas Ey i tt 15 x IMAGE DISPLA Pote DioHat Pity Lows Pasiols Dipi Satine Soa bas Layout Kis Fe pa 3 N 1 Fowl 3 60 Pasei See Hooper s 50 fio Meik i i fen Ww Sia Rare lurt a pafo Mes E pi ROSP P r Rakine fio g Rest Pict whan Filed 7 say Rasdy Pace Aami JESA forene menm SFI Aa mm Figure 5 1 1 Screen shot of data system GUI SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 65 SPEC CPI Preliminary Technical Manual Next come the control buttons check boxes radio buttons and enunciator window items on a quick access line From here the user may easily perform operations such as turn on and off the heaters De ice ON check box or take a background Users will find all of these commands in various sub menus as well but their location here provides easy access to these commonly accessed selections The enunciator window indicates to the user that probe pa
79. aning agent because it does not leave streaks as it evaporates and will not damage the AR coatings 100 pure cotton swabs and the Delrin cleaning tool provided with the CPI are also necessary Do not use a type of cotton swab that can damage the window Can of electronics grade compressed air not shown Blow compressed air over each of the windows to remove any particulates that may be present on the windows Do not tip the canned air as liquid will come out and contaminate the windows Take a cotton swab break it in half and insert one half into the hole at each end of the cleaning tool Break off the back of the swab so it is nearly flush with the Delrin rod to allow for maximum clearance Figure 6 7 3 Figure 6 7 4 Figure 6 7 5 Figure 6 7 6 is a drawing showing the relative location of each of the windows in the optical block Read through each of the following steps before proceeding further One complete swab will be used for each window Using the eyedropper from the methyl alcohol dispense one drop onto one of the half cotton swabs Figure 6 7 7 The wetted swab will first be used in a back and forth motion across the window to remove the contamination The dry half of the swab will be used to remove the residual alcohol Verify each window has been sprayed with canned air to remove particulates Scrubbing a particulate across the AR coated window will damage the coating As shown in Figure 6 7 8 insert the cleaning tool with t
80. ata is currently being recorded Live Video On tells the user that the probe is in Live Video Mode 4 Invalid Temperatures tells the user that four different temperatures are beyond their alarm limits SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 95 SPEC CPI Preliminary Technical Manual Figure 9 1 19 Enunciator Panel lights Any light other than Background Valid should prompt the user to further investigate the problem or take corrective action Live Video On can be corrected by clicking off the Live Video checkbox in the main Real Time Operation Window Figure 5 1 1 Recording Disabled can be corrected by clicking on the Record Data Checkbox in the main operators window Messages such as invalid temperature power supply out of range PDS detector invalid require the user to look at the housekeeping window to further diagnose the problem Figure 5 1 20 shows a portion of the housekeeping window with two parameters out of range One parameter is turned blue because it is below the lower alarm limit and another parameter is red because it is above the upper alarm limit i a ees 12 Voll Sappy Uw UV os Ee Mackay Sowia Input _45 Threshold Set e j016eY ra Vokes 122 psi Value Below Sie Ts Low Alarm Lirit Sng Laces Trig Timer Theeah C Damate Moa gen ara n se A iiia ue Above Upper Alarm
81. atch H IMGISR_ 15AC 48 K 12 PDS41LSR 15VDC_ 77 Q 13 PDS9OLSR 15VDC 77 eS 14 _ SpaeDC 15VDC amp a ee ee ee TMRO PMT SLS SAC 0 KU TMRI SLS LSR 115 AC O KRB O o NOTE 1 K2 K4 and K5 can be depopulated and Q5 Q6 and Q7 ait not installed can be populated to provide an alternate set of 3 15V DC heaters 7 4 CPI ROI Data File Format as given by Jeffrey Schuenke to Brad Paul and Tara Jenson on 6 23 1999 A raw roi file is structured as follows File header House Keeping block House Keeping block Frame Block House Keeping block SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 172 SPEC CPI Preliminary Technical Manual Where the HK blocks occur on second intervals until a frame block is output The frame block has priority so multiple frame blocks may occur before the next HK block If the frame blocks take more time to output than 1 second the required HK blocks are buffered and output when possible Each HK block and each Frame block has a time stamp in seconds of year Each Frame block has a matching HK block with the same time stamp This HK block will always come after the Frame block and has the deadtime value associated with the frame File header structure File version mo a SS Max Width of frame Max Height of frame BYTARR 0 Frame header St
82. ator for laser power out of range is that the Detector DC Level for either the PDS 45 or PDS 90 system is above 8 8V or below 3 5V as reported in the Lasers tab of the Settings window Figure 5 2 6 These limits are different for every probe but a well aligned probe with clean optics will have an operating range of approximately 3 5V to 8 8V If not within this range or a normal range for a given probe adjust the laser power up or down by moving the slider in the PDS 45 or PDS 90 box in the lasers tab of the Settings window This window is shown in Figure 5 2 6 Move the slider right for more power raising the DC level or left lowering the DC level Slide the adjuster to a new value and click the Apply button Monitor the DC values and the reported Laser Power Setpoint to see that the change was accepted and the DC Voltage levels are at an acceptable level Repeat the steps if necessary until the DC levels are within the above stated range If the DC Voltage remains very high even though the Laser Power Setpoint and Laser Power Actual values are low less than 18 mW then either the PDS laser is not correctly focused on the dump spot see diagram in the upper left of Figure 1 1 2 of the General Description Section 1 1 or the PDS optics are dirty and scattering laser light around the dump spot Both problems require access to the sensor head A knowledgeable person must work on the optics of the PDS system see
83. captured by the camera The imaging system is configured such that the object plane is coplanar with the backside of the rectangular volume formed by the PDS laser beams The effective imaging area is a square that is 2 5 mm x 2 5 mm 4 1 1 PDS System SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 56 SPEC CPI Preliminary Technical Manual Figure 1 1 3 is a simplified representation of the overall optical system The actual PDS systems and imaging system consist of many optical components used to achieve the desired optical performance The 90 PDS system has a beam path that makes an angle of 90 with the axis of the sample tube The 45 PDS system has a beam path that makes an angle of 45 with the axis of the sample tube Figure 4 1 1 is a solid model the 90 PDS system showing all of the individual system components Figure 4 1 1 also shows a simplified laser beam path through the 90 PDS system The actual laser beam shape as the light propagates through each optical element in the system is described using ray tracing diagrams Figure 4 1 2 is a ray trace for the PDS laser beam shaping optics The laser diodes and beam shaping optics are identical for both the 90 degree and 45 degree PDS systems The beam shaping optics are used to produce an output beam with a rectangular cross section of the appropriate dimensions and a relatively uniform energy distribution
84. ce 105 SPEC CPI Preliminary Technical Manual Settings ed Probe Disp Hist Plots Lasers PDS 45 Detector OC Level 471605 Laser Power Setport 20 20 154 miw ea oo POS 30 p etector OC Level 5 2780 W Laser Power Actual 26 24 reat IL aser Power Setpoint 26 409 miw zeng IMAGING BkoMean fiz Laser Curent Actual T Pulse Width Actual 22 9560 Vf Laser Current Setpoint 33 0517 2868 Puke Width Setpoint 22 6997 W APPLY RESET Figure 5 2 6 Lasers tab of the Settings window SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 106 SPEC CPI Preliminary Technical Manual To adjust the image mean in real time the user can check the Live Video On check box in the main screen It is best to run live video with recording disabled as about 72 full images of approximately 1 Megabyte size each will be saved to hard disk every second if recording is active Once live video is turned on the image display area will show the entire CCD camera image though for most CRT and LCD computer monitors only a fraction of the total image may be seen move the scroll bars for the image display area to view different portions of the CCD image The image mean will be updated in real time in the Img Mean field of the Statistics window see Live Video mode Section 5 1 4 4 While running live video
85. cling of Settings Corrected Faw a F d Sample Tube Temp deg Forward Sample Tube Gui es oie eee eee 20 a Optical Block 4 Temp 30 Say Central Sample Tube Temp deg C 32 3 1036 j Pylon Slug Temp C 30 95 Electronics Temp deg C 25 24 PDS_45 Laser Temp deg L 257 290 l POS 45 Laser Power Setpoint m 40 4214 4095 E POS 45 Threshold Setpoint v 0 1263 207 l Imaging Laser Current Setpoint M 32 4023 3792 j Img Laser Pulse Width Setpoint W 31 92718 3413 i Minimum Transit Time Setpoint 291 6Fe 00 35 PMT Temp Setpoint f po SLS Laser Power Setpoint 0 0 Pylon Cover Patch Setpoint 23 6399 Z O30 Imaging Lens Setpoint l Ei Laser Trigger Time Threshold lo lo Diagnostic Mode Experts Only I Missed Particle Counter is Transit Time Qualified Apply Stop Acquisition Restore Defaults Cancel Image Processing Options Secondary Wideo Display Options Threshold 40 ROI Pad 15 Mo lmage Display Ao Y Pad E f Raw Images m Ful Background Subtracted ee Fei Fim fo Background Images Generate PDS Triggers Display Image Information ROI Rejection Criteria For Each Image D Fre Set Rls Mehun Periodic Statistics Min Size Pixels a Background Options Fill Ratio 7 be 0U6 il Ratio eB E Update Background Now Image Display Mode aln T da T da q spect Ratio Aspect Ratio gt 1 wre SPEC CPI Preliminary
86. cquisition System Connect the sensor camera cable to J1 on the Data Acquisition System only DO NOT connect the other end to the Sensor Head yet Before making connections to the Sensor Head electrostatic discharge ESD precautions should be taken It is assumed that if the CPI Sensor Head is mounted on the aircraft the CPI pylon is grounded to the aircraft frame It is also assumed that if the Data Acquisition System is mounted in a metal frame inside the aircraft that it is also grounded to the aircraft frame In this case no extra ground wire is needed However if the CPI Sensor Head is lying outside and is not mounted or if the Data Acquisition System is not mounted then a temporary ground wire should be run between the CPI pylon and the Data Acquisition System Chassis If the Data Acquisition System Chassis is grounded to the aircraft frame then the ground wire may alternatively be run from the pylon to the aircraft frame This will ensure that the Sensor Head and the Data Acquisition System Chassis are at the same electrical potential when the cables are connected The person making the cable connections should be grounded to the CPI pylon by using a ground strap or by touching a screw on the outside of the CPI pylon Connect the power dsp cable that runs from J2 on the Data Acquisition System to J2 on the sensor Head See Figure 2 2 4 Connecting the power dsp cable to the Sensor Head Connect the sensor camera cable that runs from J1 o
87. cribed above also goes to the pulse peak detector U19 as shown in the block diagram in Figure 4 2 1 The output of U19 goes to an A D converter and the corresponding analog to digital converted ADC value is sent to the Data Acquisition System in the PDS packet The PDS packet is stored in the roi file along with the image s of the particle s that triggered the PDS event This allows data analysts to correlate the size and shape of the particle with the amount of light it scattered past the dump spot and into the APD detector SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 49 SPEC CPI Preliminary Technical Manual To Analog to digital Low Pass Converter for Filter amp Housekeeping Data To Logic High Pass Comparator APD Detector IC U20 Filter U18 amp Analog Wave Shaping To A D Converter Gets sent to Data Baseline PDS Pulse Acquisition Restoration Peak Circuit 04 Detector U19 Figure 4 2 1 Block Diagram of PDS 45 Analog Electronics Volts PDS _ 45 Digital Output P45 THR PDS 45AC Comparator Threshold AC Coupled APD45 Signal Time Figure 4 2 2 AC coupled APD PDS_45 signal comparator threshold and resultant digital output SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice ot SPEC CPI Preliminary Technical Manual 4 2 2 PDS Logic and
88. ction 5 3 The Advanced Control and Settings selection is discussed next 5 1 2 1 Advanced Control and Settings Window Selecting the Advanced Control and Settings item in the settings menu of Figure 5 1 5 brings up the window shown in Figure 5 1 6 The upper section of the window is much like that of the housekeeping window The set points for various probe parameters are defined in this window by the user and sent to the probe by hitting the Apply button The left side contains heater enable radio buttons instead of status indicators and the right side has parameter set points instead of observed values For most of the parameters in this window such as temperature zone set points and laser powers when the user enters a new value and then hits the apply button a corresponding change in the housekeeping data will occur as the CPI sensor Digital Signal Processor DSP responds to the new set point values Disabling the De Ice Heat radio button black means it is enabled as shown white means it is disabled disables temperature controlling at the sensor head If disabled no heaters will be turned on regardless of the monitored temperature values If De lce Heat is enabled the sensor head DSP control board Section 3 1 Figure 3 1 5 will monitor the measured temperatures of the selectively enabled heat zones enabled by selecting them with the radio buttons on the left side of Figure 5 1 6 and if th
89. d software at any time and without notice 45 SPEC CPI Preliminary Technical Manual 45 PDS LASER IMAGE LASER ASSEMBLY 45 PDS INPUT INPUT ASSEMBLY MIRROR 390 PDS OUTPUT ASSEMBLY DUMPSPOT 4sppsouTPUT IMAGE LENS ASSEMBLIES ASSEMBLY TILT ADJUSTMENT SCREWS Figure 4 1 7 Location of optical components visible from top side of internal sensor SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 46 SPEC CPI Preliminary Technical Manual 30 POS INPUT 90 PDS LASER IMAGING LASER ASSEMBLY PULSER IMAGING IMAGE FOLD SS IMAGE LENS TILT MIRROR LOCK SCREW ADJUSTMENT SCREWS Figure 4 1 8 Location of optical components visible from bottom side of internal sensor SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 47 SPEC CPI Preliminary Technical Manual PDS 30 DETECTOR PDS 45 DETECTOR IMAGE MIRROR TILT SCREWS IMAGE LENS FOCUS ADJUST IMAGE MIRROR LOCK SCREW Figure 4 1 9 Location of optical components visible from front side of internal sensor 4 2 Detailed Description of Electronics The electronic assembly is comprised of three printed circuit boards They are the Digital Signal Processor DSP board the Relay board and the Power board not to be confused with the sensor head power supply which is located in the Data Acquisition
90. ding to the size of an image in microns that will fit in the ROI box Not all DX and DY values will work for a given set of column and row numbers so experimentation is required Settings es Particle Display Settings Size um Layout Frame Skips E Particle Size Histogram Interval Jig Plot it fw Update 1 Bins 20 24 Size Range um Min lo Max 250 7 ROI Ar Plot Plot it Max ROls in Plot fi O00 Reset Plot When Filled w APPLY Figure 9 1 15 Disp Hist tab of the Settings window A close up of eight ROI display boxes is shown in Figure 5 1 16 Beneath each ROI box is the x and y location on the CCD in pixels of the ROI the total size of the ROI in the box in microns including the pad not the total size displayed which is DX and DY above and the time the ROI was captured If more than one ROI is captured in a single frame ROI display boxes will be SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 89 SPEC CPI Preliminary Technical Manual plotted one after the other with the x and y location total size of the ROI and the time displayed in the same color descriptions to give the user a visual cue that this has occurred The color of each sequential frame alternates In the example of Figure 5 1 16 some displayed ROls are portions of a background as identified by the reported Bkg information otherwise the frame
91. dow Particle Display arto Qld Stats Window w Command Bar Bkg Annunciator s w Status Bar Figure 5 1 2 The View drop down menu used for selecting the Housekeeping window Figure 5 1 2 shows a screen shot of the View menu The Housekeeping and Stats Window selection items will be discussed in the following sections The SPP100 Data Single Board Computer and Serial Data selections are for customized use and not described in this manual SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 66 SPEC CPI Preliminary Technical Manual The other 5 items display or remove windows that will not be described but which the user may wish to experiment with by selecting and deselecting from this menu 5 1 1 1 Housekeeping Window selecting the first item in the View menu opens the housekeeping window shown in Figure 5 1 3 Here the user may observe all the measured parameters of the operating probe in one window The housekeeping data is used to evaluate the status or health of the probe by monitoring such engineering parameters as internal temperatures power supply voltages pylon internal pressure etc Real time values for laser powers and actively controlled temperature zones are also contained in the housekeeping data The right side of the window shows housekeeping parameters measured in the last second by the probe e
92. e a particle is present in the object plane A 1024 x 1024 pixel CCD camera captures the image of the particle and transfers the frame to the data system A previously stored background image is subtracted from the newly acquired image and the result is a region of interest ROI that contains an image of the cloud particle The camera runs at approximately 74 frames per second The laser used for the imaging system is a stacked array consisting of three emitters A 600 um core multimode fiber is butt coupled to the face of the stacked array The fiber is used to provide an output beam that is circularized and has a relatively uniform energy distribution The output from each of the laser segments is blended together as the beam SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 42 SPEC CPI Preliminary Technical Manual propagates through the fiber resulting in a much more uniform energy distribution than would be otherwise achievable The laser operates at a wavelength of 810 nm and has an output power greater than 120 W The fiber is terminated with an SMA style fiber connector The connector screws into a collimating barrel that uses an aspheric lens to collimate the output of the fiber IMAGE COLLIMATING IMAGE LASER BARREL io ae INPUT MIRROR IMAGE LASER we INPUT WINDOW x MAGE LASER OUTPUT WINDOW CORRECTION PLATE 4 SAMPLE VOLUME IMAGE FOLD
93. e e N 1 750 R2 250 2X 7 375 2 4 500 2X 13 575 2x 11 875 2X 10 375 2 6 875 2 8 375 2 5 675 U HIS OF TeWEr sero out Wee SP EC N E _ TYPICAL AIRCRAFT INSTALLATION WOULD NOT USE FS saci Ra l LE pa ALL FASTENER HOLES BUT A MINIMUM OF 7X 1 4 26 the aa Sie OR 5X 1 4 26 AND 4X 6 32 raran craw ea HOLE LOCATIONS OTS SEE DAC NG FEV v v Hee A ry b B A ANH SCAIENI WEICHI SHEELZO Figure 7 1 2 Pylon Interface SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 160 SPEC CPI Preliminary Technical Manual 550 2 6377 464 49 iii Ooo o omeia 180 73 25 4 IE CEET CEA n e A mas f a a ies E E 2236 ole 2 35 56 te a pe Sef i eres x A EN G aes ee Z T Ae eas ii pri vO LUME iddi oi ae Peas 2 5 Wha TILTED j Figure 7 1 3 Flow Geometry Dimensions 7 2 CPI INI 1 System 2 CameraType 1 3 ProbeRev 3 4 PixelPolarity 0 5 ROI Parameters 6 ImageType 33280 7 DispMode 0 8 StartDrive 4 1 15 9 DriveCount l1 1 6 LO BackgroundRate 600 10 36000 LEs BkgPDSThreshold 10 1 35 Tzs ROIThreshold 40 20 150 lee ImgMeanMin 63 1 70 14 ImgMeanMax 195 160 255 Log ROIMinSize 4 0 400 SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice Eol Los EIs LOs ES Ze Zeit Lie LB 2A
94. e green handles position the internal sensor mount points above the test stand mounting plate Figure 6 4 3 SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 131 SPEC CPI Preliminary Technical Manual 4 While holding onto the green handles on the internal sensor screw one of the mount screws into the internal sensor mount point only a few threads Figure 6 4 4 5 While holding onto the green handles on the internal sensor screw the opposite mounting screw into the internal sensor mount point only a few threads Figure 6 4 5 When both screws have been started alternate turning them until they are tight and the mount plate is completely flush with the internal sensor 6 After the mount screws have been completely tightened verify the universal joint screw is completely tight Figure 6 4 6 7 Verify that sensor power and computer power are off 8 Figure 6 4 7 shows the connectors for the sensor end of the test cables Connect the opposite ends of the test cables to the data acquisition system as described in the CPI connection procedure 9 Using a clamp strain relieve the test cables to the table to avoid any stress on the connectors when they are mounted to the sensor head Figure 6 4 8 10 Mate the J21S DC power connectors Figure 6 4 9 11 Mate the J20S AC power connectors Figure 6 4 10 12 Mate the J22S DSP data connectors Figure 6 4 11
95. e it to S8 and back to SO Recall that if the PDS 45 avalanche photodiode detector APD sees a particle then the output of comparator U18 will go high Likewise if the PDS 90 APD sees a particle then the output of comparator U26 will go high The PDS digital processing electronics looks to see that both the PDS 45 and PDS 90 signals go high then starts a minimum transit time counter Once a minimum transit time user set is exceeded the PIB_OK signal goes high internal to U20 The minimum transit time is shown as T Transit Qualify in Figure 4 2 3 This causes the state machine to advance from S0 to S1 When either the PDS 45 or PDS 90 signal goes low the PIB_OK signal goes low which causes the state machine to go from S1 to S2 S2 forces the imaging laser to immediately fire a short 20 nanosecond pulse of high intensity laser light illuminating the detected particle onto the BASLER A501 CCD camera At the same time the PDS STATUS signal goes high The PDS STATUS signal tells the Data Acquisition system that the next image downloaded from the CCD camera contains at least one particle and therefore should not be discarded The state machine then advances from S2 to S3 In S3 the state machine outputs an interrupt signal to the digital signal processor DSP This Notifies the DSP that a particle was seen so that it can send a PDS packet to the data acquisition system A PDS data packet accompanies each particle image with particle
96. e temperature is below the set point value turn on a heater in the appropriate sensor head zone The set points for heaters and other parameters are located on the right side of the Advanced Control and Settings window with the Corrected and Raw column labels having the same meaning as previously described for the housekeeping window By selecting one of the displayed values such as the Forward Sample Tube Temp on the first line right side a user can adjust the set point in two ways First one can type in a new number either raw or corrected the corresponding value in the other field will change Second once a field is highlighted one may use the slider bar located immediately right of the Raw column to adjust the values SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice es SPEC CPI Preliminary Technical Manual Probe and Image Processing Settings a olx Heater Enables Optical Block A Optical Black B OEO iio Central Sample Tube Aft Sample Tube Pylon Cover Patch Pylon Slug Pylon Base Patch Imaging Lens Spare DL Camera PMT SLS Laser APD 45 Amplifier APD 90 Amplifier Imaging Laser Pulser POS 45 Laser POS 90 Lager Oio a YY io YY De lce Heat File Save Options fi Recording Disabled Img Laser Trig Timer Th Drive for Next File D Drive Count li Enable Cy
97. egister 0 W Laser Pulse Timer 0x500 W W W W W W W S I WwW I w I R I w I R I w pot R I w I R I w l W Each of these reads and writes is discussed below These writes occur in I O memory space and require two separate I O 1K pages The first will be at page 8 0x2000 7 3 1 Reads l Housekeeping ADC R W 0x2000 On a read the AD7878 ADC 1s read from the control board into data bus D 0 11 Dead Time Read 0x4000 A 24 bit counter is clocked off of the 12 MHz clock whenever a particle event that is transit time qualified is not occurring The upper 12 bits of this counter DT 23 12 are read and cleared by reading this address Transit Timer Read 0x5000 This 11 bit counter is clocked at 48 MHz for the duration of a valid particle event It should be read every time a particle event interrupt from the PDS state machine occurs Total Particle Counter Read 0x5001 This 10 bit counter is clocked every time a valid particle event occurs If MT 12 is a 1 a valid particle event is one in which the particle is detected for a minimum transit time default otherwise it occurs whenever both PDS signals show a particles presence Status Register Read 0x5002 This PDET bit read on DO is high if a particle event interrupt has occurred SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any
98. egular intervals the period of which is set by the user If the DAS fails to get a valid background in a reasonable amount of time the enunciator panel displays a red warning of Background Failed If the DAS has just started communicating with the sensor head too many repeated failed attempts to acquire a background will cause the program to stop communications with the sensor head These failures and others and their solutions will be explained in Real Time Operation and Troubleshooting Section 5 2 Changing Particle Threshold Minimum Pixel Size Strobes Threshold Minimum and Maximum Image Mean and Background Rate All of these parameters except Minimum and Maximum Image Mean are readily changed in the Probe tab of the Settings window shown in Figure 5 1 8 All of these parameters are located in the Advanced Control and Settings window located at bottom center A cut out of the image control section of the Advanced Control and Settings window is shown in Figure 5 1 11 Note that the Strobes Threshold of Figure 5 1 8 is labeled Max PDS Rate in the Advanced Control and Settings window they are the same parameter Remember that changes to the parameters are not active until the Apply button is clicked whether in the Settings or the Advanced Control and Settings windows Image Processing Options Secondary Video Display Options Threshold 4 2 Image Display Mode ROI P
99. ent after removal Removal of the internal sensor from the pylon should only be performed by personnel who have read and become familiar with this procedure If this procedure is not followed correctly the optical alignment of the CPI may be compromised or damage to components of the CPI may result 1 Verify CPI sensor head power and computer power are turned off 2 Verify the pylon cover removal procedure has been followed correctly 3 Verify the PCB retaining clip is locking the PCB into place see Pylon Cover Removal Procedure 4 Figure 6 3 1 shows the primary mount points for the internal sensor in the pylon with the internal sensor removed for clarity In the installed position the internal sensor is mounted to two O rings on the inlet adapter two O rings on the aft sample tube and a robber grommet on the pylon SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 124 SPEC CPI Preliminary Technical Manual spreader The O rings and grommet serve to vibration isolate the internal sensor from the pylon as it is free to float a small amount on these points The O rings also serve as a hermetic seal between the sample tube and internal pylon 5 Figure 6 3 2 shows the general location of the connectors that need to be de mated 6 De mate both base and full cables from the camera Figure 6 3 3 7 De mate the J23S internal pylon connector from the connect
100. ep en gpa A EUU UNBN gt gt SS wn Mm B H h gt A K O wH NM O ou Particle Size um Figure 5 1 17 The particle histogram plot used to size particles in real time The histogram plot uses two colors red and green in plotting The two are plotted alternately in order to contrast current measurements with past measurements Two other parameters in Figure 5 1 15 Interval and Update affect how often the current color is updated update and for how long each color is plotted interval For example if update is 1 sec and interval is 5 sec every 1 sec the histogram will update and every 5 sec the counting will alternate between green and red If update is 5 sec and interval is 20 there will be 4 updates between red and green changing To remove the histogram display either click on the minimize button in the upper right of the histogram window or uncheck the Plot it box in the Settings window The last plot of interest shows the location of detected particle ROI locations shown in Figure 5 1 18 Each ROl s top left corner and lower right corner are plotted in red and green respectively against x and y pixel coordinates of the CCD camera Thus each axis range is 1 to1024 This plot provides a visual means of identifying how uniformly the PDS system detects particles in the sample volume If the ROI locations become biased to one side of this plot there is likely a problem with the PDS electro optical system
101. erface between air and cloud particles flowing through the sample tube and the internal structure of the CPI The sample volume is located in the center of the sample tube running through the optical block This relationship is depicted in Figure 1 1 2 After the PDS laser beam traverses the sample volume and exits the optical block it intersects the PDS collection optics The PDS collection optics are designed to collect light scattered by particles in the sample volume and focus it onto the APD which acts as the PDS detector The PDS collection optics and dump spot define the collection angle for the PDS system In this case both PDS systems have been designed to collect light scattered into an angle of approximately 2 5 OZ Figure 4 1 3 is a ray trace for the 90 PDS collection optical system In this figure the sample volume is on the left side and the PDS detector is located on the right side Four separate ray traces are shown Figure s 4 1 3a and 4 1 3b show the PDS laser beam as it is blocked by the dump spot when no particle is present in the sample volume Figure 4 1 3a shows the beam in the X Z plane 0 5 mm dimension and Figure 4 1 3b shows the beam shape for the Y Z plane 2 5 mm dimension The beam size on the dump spot is relatively the same size as that in the sample volume even though it has passed through 90 PDS Collection Lens1 and 90 PDS Collection Lens2 The spacing between the various optical elements is shown in Figure 4
102. erformed by personnel who have read and become familiar with this procedure 1 Verify CPI sensor head power is turned off 2 Figure 6 6 1 shows the important areas of the pylon cover that must be aligned during installation of the pylon cover 3 Figure 6 6 2 shows the important areas of the pylon body that must be aligned during installation of the pylon cover 4 Hold the pylon cover as shown in Figure 6 6 3 and gradually lower onto the pylon body so the tongue and groove and pylon connector are aligned SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice r4 SPEC CPI Preliminary Technical Manual 5 Gently lower the pylon cover into the position shown in Figure 6 6 4 If the pylon cover is not properly aligned it will not be flush with the pylon body at this time 6 Study Figure 6 6 5 through Figure 6 6 11 before proceeding further 7 Using the T15 Torx plus driver install the center pylon fastener but do not tighten it down completely Figure 6 6 5 It may be necessary to push the pylon cover down by hand slightly to maintain alignment of the tongue and groove while the center fastener is being tightened 8 21X 8 32 Torx plus fasteners are used to fasten the pylon cover to the pylon body Figure 6 6 5 and Figure 6 6 6 19 of the fasteners are 3 4 long while 2 of the fasteners are only 2 long The locations on the pylon cover for the sh
103. es SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice bi SPEC CPI Preliminary Technical Manual 2 Ifthe sum of the laser flashes per second over the duration of X5 seconds is lt X6 start with X5 30 X6 2 then lower the PDS threshold by X7 start with X7 50 Figure 5 3 2 shows the form used to change the parameters that affect this algorithm with the upper third of the form controlling the PDS threshold contro parameters To turn off the PDS Threshold Level control algorithm so that the real time software lets the user maintain control leave the Algorithm Enabled checkbox unchecked The parameters in the form are all described in the description of the control algorithm above Note that item number 1 in the algorithm raises the threshold if a number of particles have been detected via imaging laser flashes over a given time period but the percentage of valid frames frames containing valid particles or regions of interest denoted as ROI s is low The assumption is increasing the PDS thresholds will increase the valid frames Item 2 in the algorithm decreases the PDS threshold if over a long period of time very few X6 laser flashes occur In clear air with no particles present this algorithm will decrease the PDS thresholds enough to cause light and optical noise to just begin triggering the PDS system This is the optimum sensitivity setting
104. eserves the right to make improvements and changes to the CPI and related software at any time and without notice t19 SPEC CPI Preliminary Technical Manual Figure 6 1 1 F gure 6 1 2 Figure 6 1 3 Figure 6 1 4 bos a tee S CONNECT E Figure 6 1 5 SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 120 SPEC CPI Preliminary Technical Manual Figure 6 1 6 21X 8 32 TORX PLUS PYLON FASTENERS Figure 6 1 8 Figure 6 1 10 Figure 6 1 11 SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 121 SPEC CPI Preliminary Technical Manual PLACEPYLONCOVER ON A SOFT FOAM SURFACE TO AVOID DAMAGE Figure 6 1 12 Figure 6 1 13 ne AG PYLON Bopy PYLON COVER y s S Ey 7 fm CONNECTOR GR CONNECTOR F CENTER O RING TONGUE PRECISION MACHINED O RING MATING amp SURFACE Figure 6 1 14 Figure 6 1 15 6 2 CPI DSP Control Board Access When Internal Sensor Head Is Mounted in the Pylon The following steps describe how to access the DSP control board also called printed circuit board PCB for troubleshooting when the instrument in mounted in the pylon The ability to access the PCB in the pylon can be particularly useful when the instrument is mounted to an aircraft
105. eters should not be changed directly using a text editor such as Notepad Some of these parameters are manipulated by the user from within the CPl exe program but will be explained in following sections that describe the DAS graphical user interface GUI Next comes the Probe Settings heading This section contains the first parameters a user may need to change directly For example on lines 26 and 27 the cpi INI file contains the following Setting Forward Sample Tube Temp set point setting1 95 0 957 Current set point Upper limit Lower limit Note that the semicolon indicates that the information on line 26 is for the user s information only the DAS does not do anything with it Line 26 tells the user that the next line contains the temperature set point for the Forward Sample Tube The three numbers from left to right are 1 The current set point 2 The lower limit of the set point 3 The upper limit of the set point The current set point value is written to the file every time the CPl exe program is shutdown by the user The lower and upper limits set the acceptable set point range for the particular parameter These limits serve as the slider limits in the advanced control and settings window Ifa value is manually typed in that is not within range an error message will appear Probe set point out of range The only numbers the user may need to change from within a text editor are items 2 and 3 SPEC Inc re
106. flight operations Monitoring the threshold Voltage and the AC coupled PDS signal to the comparator is possible in a laboratory environment using an oscilloscope and reading the Detailed Description of Electronics Section 4 2 Another option during flight and in the lab is to use the artificial intelligence Al PDS DC level and threshold adjustment algorithms discussed in Section 5 3 The Al algorithm has been successfully used during flights of the original CPI not the one for which this manual was written but which has very similar operational parameters in which there was no user control of the CPI The Al code successfully optimized the settings of the PDS system on every flight and is an option users may prefer even during flights in which an operator is present Reading how the Al control works will also provide insight into how to optimize the PDS settings 5 1 3 3 PDS Minimum Transit Time Control The minimum transit time is programmable and is the amount of time a particle passing through the sample volume must cause both the PDS 45 and PDS 90 comparators to go high for the PDS logic to recognize the particle as valid See the electronics description in Section 4 2 and Figure 5 1 8 for more information The Raw value for the transit time is entered in the Advanced Control and Settings window of Figure 5 1 6 in the Minimum Transit Time Setpoint field Alternatively the corrected time may be entered in the Settings w
107. g the PDS 45 Laser Power Actual as well as current set points used by the probe e g the PDS 45 Laser Power Set point The column labeled RAW contains analog to digital ADC and digital to analog DAC converter values currently measured or set by the probe and DAS Using the PDS 45 laser again as an example the PDS 45 Laser Power Actual value of 876 seen in Figure 5 1 3 19t item down is the result of an ADC conversion taken in the last second the PDS 45 Laser Power Set point value of 2123 29th item down is the current DAC setting generating a Voltage in an electronic servo loop that forces the PDS 45 laser to 20 154 mW as seen in the column labeled Corrected The Corrected column values have units such as mW and degrees C and use coefficients from the cpi INI file described in Section 5 1 7 Noting that the set and measured raw values for the PDS 45 laser power are quite different 876 and 2123 but that the corrected values are quite close 19 938 mW and 20 154 mW respectively one observes that the set point and observed coefficients are often different for the same parameter in this case the laser power On the left side of the housekeeping window is a set of radio buttons labeled Heater Status The button at the bottom of this section labeled De Ice Heat would be enabled black if the heaters are currently chosen active by the user If so the CPI sensor head will turn on heaters if any region t
108. ges to the CPI and related software at any time and without notice 23 SPEC CPI Preliminary Technical Manual sepi g a x oe isj x File View Settings Commands Help Live START j Hecord TAKE Freeze PROBE a E Bate ee Der ON IE i isplay sertas Initializing the Probe Initializing the Probe PROBE INITIALIZED ss MUM Ready Bsn ACSE Ba AS isn Figure 2 4 4 CPI Program Screen While It Is Initializing the Probe 9 Once the Probe is initialized you should see the CPI startup screen which contains a particle image display window with at least one background image Also you should see a Statistics window on the right hand side of the screen as shown in Figure 2 4 5 If you see a screen like Figure 2 4 5 then your CPI has been started correctly and is running See the Software Description and Real Time Operation Section 5 for further instructions on fine tuning and running your CPI If you DO NOT see a screen like Figure 2 4 5 then the software or probe has a problem Review the CPI cable connection procedure and CPI startup procedure to make sure that they were done correctly If these procedures were followed correctly then please see the Real Time Operation and Troubleshooting Section 5 2 SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 24 SPEC CPI Preliminary Technical Manual
109. ging laser it is the total incident light energy of this pulse that must be adjusted to change the image brightness and mean This is important because if an image is too bright or too dark it may not respond linearly to the occultation of the laser by passing particles and sensed particles may not be correctly imaged How many Joules of light energy reach the camera are set by changing two imaging laser parameters Laser Current Setpoint and Pulse Width Setpoint as accessed via the Laser tab of the Settings window shown in Figure 5 1 7 These parameters are also accessed in the Advanced Control and Settings window on the right side found in Figure 5 1 6 Generally the DAS is set to run the imaging laser current at a safe maximum when the CPI is manufactured and users should need change only the laser pulse width The laser power is approximately constant but for a duration controlled by the Pulse Width Set Point parameter The parameter is given in Voltage units but the maximum Voltage corresponds to approximately 40 nS this varies slightly from instrument to instrument Setting a lower applied Voltage decreases the time the laser is on when it pulses thus lowering the amount of light energy to the CCD camera and lowering the image mean 9 1 4 4 LIVE VIDEO MODE To adjust the image mean in real time the user can check the Live Video On check box shown in the upper left of Figure 5 1 1 in the mai
110. gorithm Enabled POS OC Level Control Laser 90 F Algorithm Enabled Volts Counts Target DC Level fe a 2002 Err Thresh Start Change Jas f 14 En Thresh Stop Change ja2 46 Stable State Max Range ja es Min Stability Time Pernod sec 20 Averaging Time Period sec 20 Volts Counts Target DC Level EE 2002 4 Err Thresh Start Change as f Err Thresh Stop Change 0 2 46 Stable State Max Aange a3 fes Min Stability Time Perod sec 20 Averaging Time Period sec 20 Adaptation Parameter Ki T as Adaptation Parameter Kp 0 25 f T Adaptation Parameter Ki T Adaptation Parameter Kp blasimum Iterations Masinurn Iterations REKE Apply Cancel Figure 5 3 2 PDS threshold and DC level control form The following is a description of the parameters affecting the PDS laser DC level control Note that both the PDS45 and PDS90 lasers have settings that need entered but should usually be the same One possible difference is the target DC level Target DC Level This comes from the cpi ini file in the C Winnt directory Gain Offset 20 line 173 of the example ini file in the appendix and Gain Offset 22 line 179 of the example ini file in the appendix the max value entered in the file is used as the target DC level This value is not editable in the form shown in Figure 5 3 2 Err Thresh Start Change Volts away from the target for the algorithm to go acti
111. h between Images Update Step i T Enable Mean Error E vent Background Adaptation Enable Back dAdantation Uverlap AUls StS ee Cues are Check Period 1 hax lonce frames E eE 3 Overlapped AOI poo Count limit 0 Apply Cancel Figure 5 3 3 Background and image laser setting control form The parameters that affect the background algorithm are described below Check Period Once every Check Period frames the image processing algorithm will look for ROPs that overlap If this value is 1 the data system will monitor every frame If value is 2 the data system will monitor every other frame Choosing bigger numbers makes the system faster Overlap ROls Pixel Offset Limit See Figure 5 4 3 Two corners of possible overlapping ROls are compared The comparison calculation for the upper left corner points P is explained here but the calculation for the lower right corner is similar For the points P1 and P2 If X1 X2 lt Overlap ROIs Pixel Offset Limit AND Y1 Y2 lt Overlap ROIs Pixel Offset Limit then the upper left corners overlap If upper left corners P1 and P2 overlap AND lower right corners Q1 and Q2 overlap then the two ROPs are considered overlapping Due to very small changes in the optical and electronic systems the image of even a fixed dust particle stuck on a lens will move around by a few pixels from frame to frame Overlap ROIs Pixel Offset Limit allows the Al alg
112. hat is individually enabled see Section 5 1 2 1 has a measured temperature less than its set point If a heater was on during the last second the sensor head reports that this is the case and the corresponding radio button will be active black In Figure 5 1 2 the De lce Heat is off and thus correctly there are no heaters displayed as currently on The other reported values on the top left side of the window Include the update rate set to once per second in the window the time reported by the probe when it sent its most recent housekeeping information which it does once per second the command number which should increment every time probe operating commands are sent from the DAS to the sensor head see Section 5 1 2 1 the laser strobes count which is the number of times the imaging laser was flashed in the last second because a particle was detected and the dead time which Is the sum of the small windows of time during which the probe was processing a particle and therefore could not acquire a subsequent particle if there was one This sum is taken over a period of one second The two radio buttons at the bottom left of the housekeeping window indicate current sensor head settings for parameters that may be used in the future but currently should always be off white SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 67 SPEC CPI Preliminary Technical Ma
113. he computer monitor If the pinpoint is not at this position adjust the image mirror tilt screws Figure 6 8 9 until the pin is centered It is first necessary to loosen the image mirror lock screw shown in Figure 6 8 9 before adjusting the tilt screws 9 Turn off the PDS lasers shown in Figure 6 8 10 and the point of the pin should be exactly in focus Slide the pin in and out of the optical block slightly to see how it looks when it goes in and out of focus 10 If the pinpoint is not exactly in focus as shown in Figure 6 8 10 at this position in the sample volume it is necessary to adjust the focus This is accomplished by pulling water drops through the probe and adjusting the image lens focus adjustment shown in Figure 6 8 9 11 Following the procedure describing how to set up the droplet atomizer pull particles through the probe and observe the ROI images Live Video Mode must be turned off PDS lasers turned on 12 The focus adjustment barrel is locked in place with a piece of aluminum tape and a lock screw Remove the tape and slightly loosen the lock screw with an allen wrench The focus adjustment should be rotated Figure 6 8 12 until the majority of the images are in focus as shown in Figure 6 8 11 Note even for the best focus there will always be some out of focus particles present The goal is to maximize the number of particles in focus As you rotate the barrel it is apparent what constitutes an out of focus image SP
114. he internal temperature of the sensor head to become overly warm Shut down the instrument including instrument power if the Power supply board or DSP temperature exceed 45C 5 1 6 Display Options Aside from the displays previously discussed some derived parameters size histograms and ways of looking at and storing particle images are available to the user 5 1 6 1 Rates and Image Parameters some of these were discussed in Section 1 and seen in Figure 5 1 1 More are available to the user via the Settings window in the Plots tab shown in Figure 5 1 14 SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 87 SPEC CPI Preliminary Technical Manual Settings es Computed Rates per sec Frames Captured Frames Attempted Walid Frames raged Particles Particle Concentration ROI Concentration PDS Strobes Laser Strobes VT 1 1s st Values for Last Frame Image Mean P Transit Time E Missed POS E r raged Particles Figure 5 1 14 Plots tab of the Settings window for selecting items to display in the Rates and Image Parameters plot A short description of each item available for plotting follows 1 Frames Captured The number of frames in which the DAS found particles and cut out ROls 2 Frames Attempted The number of frames the DAS searched for particles due to correlated PDS STATUS having value of one
115. he wetted end of the swab first clean and dry only the window you are targeting Observe the result of the cleaning in the real time software The cleaning tool is inserted in the direction of airflow through the probe from the end where the nose cone mounts Each of the optical systems should be cleaned in order and each window must be specifically targeted Figure 6 7 9 For the PDS systems verify the lasers are at full power Observing the PDS 45 detector DC level clean and dry the input window and observe the DC level If it slightly decreased or stayed the same move onto the PDS 45 output window If the DC level increased during cleaning that window should be cleaned again until the DC level decreases or stays the same View the PDS 90 DC level and clean the windows for that optical system SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 146 SPEC CPI Preliminary Technical Manual 43 Figure 6 7 10 shows the DC levels reduced to satisfactory values after cleaning 44 Clean the imaging system windows Figure 6 7 9 Before cleaning the imaging system windows run the probe in Live Video Mode and locate any contamination visible by the CCD array Observe the effect of the cleaning on the CCD array image there should be fewer contaminants visible after cleaning Also observe the image mean in real time The image mean should increase or stay the same after
116. he window The result is an astigmatism that makes a spherical water drop look elliptical The correction plate is a plane parallel element that is tilted at a specific angle to nullify the astigmatism Table 4 1 1 is a summary of the optical specifications for the CPI Table 4 1 1 CPI optical specifications VALUE UNITS 2 5 X 2 5 mm x mm Sample area Pixel resolution 2 4 um pixel camera array size 1024 x 1280 pixels x pixels camera pixel size 12x 12 um Max Frame Rate 74 at 1024 x 1024 frames per second at pixels x pixels Image system primary 5X Linear magnification magnification SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 44 SPEC CPI Preliminary Technical Manual Image laser wavelength Image laser power Image laser pulse max pulse width Image laser max pulse frequency PDS laser wavelength PDS laser max power PDS beam size PDS collection angle 4 1 3 Physical Location of Optical Components 810 120 40 74 currently 785 40 0 5 x 2 5 2 92 Oc Nm Ns Hz nm mW cw mm x mm Degrees Figures 4 1 7 4 1 8 and 4 1 9 show the location of each of the optical components described above The figures should be used as a reference when trying to locate various optical components in the internal sensor head SPEC Inc reserves the right to make improvements and changes to the CPI and relate
117. ical Manual m A i kh gt CAMERA CONNECTOR 7 CABLES COMPLETELY f i 1 CONNECTED AND STRAIN RELIEVED Fi a h ee INSTRUMENT READY TO POWER ON mr EVAS iid z ma Figure 6 4 12 Figure 6 4 13 6 5 CPI Internal Sensor Installation into Pylon The CPI internal sensor must be installed into the pylon for airborne operation The following photographs show the sensor head lying flat on a table The same procedure is followed if the sensor head is mounted on an aircraft When not mounted to an aircraft the pylon should always be placed on a soft material such as foam to avoid scratching the outer surface CAUTION The CPI internal sensor head is a high performance assembly that consists of many optical components electro optics assemblies and ESD sensitive electronics The pylon serves as a protective housing for the internal sensor head When the internal sensor head is removed from the pylon the optics are no longer protected from contamination Installation of the internal sensor into the pylon should only be performed by personnel who have read and become familiar with this procedure If this procedure is not followed correctly the optical alignment of the CP may be compromised or damage to components of the CPI may result 1 Verify CPI sensor head power and computer power are turned off 2 Remove the internal sensor from the test stand following the correct procedure Figure 6 5 1 3 Verify the aft sample
118. id the DAS Complete the Allocating Memory And Initializing Probe Processes No Is Sensor Head Power On Yes No Turn it on and try again There a valid Background See the Back ground Section Yes 5 2 3 All Cables Connected Connect cables Per Instructions in section2 2 and See the Back Try again See the RTIA ground Section Yes Log section 5 2 3 5 2 2 No background meari Is the probe getting ROIS in the presence of particles No Yes See the PDS system section Are there Red or blue flashing Enunciators Yes 5 2 4 See the No enunciator warning limits section 5 2 5 Enjoy the flight your probe is working Figure 5 2 1 Troubleshooting flow chart data system access only SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 23 SPEC CPI Preliminary Technical Manual 9 2 2 RTIA Log Troubleshooting The rtialog txt file is found in the following directory C Program Files boulderimaginginc acquirenow cpi directory This file is produced every time the probe is run and is written with information that is useful for troubleshooting many different problems some of which are described here The following RTIA subsection headings describe the problem such as sensor head powered off and the information in that section includes line
119. ield14 Vertical Velocity m s 6 1f 284 Fieldi5 4PI Top Channel a 5ld 239 Fieldlo6 4PI Top Channel OI 5ld LOO Field17 4PI North Channel a 5ld Des Field1l8 4PI North Channel b 5ld ZOO Field19 4PI East Channel a 5ld ZOO Field20 4PI East Channel b 5ld VAS ICT Field21 4PI South Channel a 5ld 2 Ol Field22 4PI South Channel b 5ld ZO 2s Field23 4PI West Channel a 5ld ZO Ss Field24 4PI West Channel b 5ld 294 Field25 4PI Bottom Channel a 5ld ASIS Field26 4PI Bottom Channel b 5ld Zoe Field27 Primary Voltage V 5 1f ZO a Field28 Primary Current A 5 3f 298 Field29 Extra Voltage 1 V 7 5f 299 Field30 Extra Voltage 2 V 7 5f 300 SampleInterval 1 oie vile HistoryLength 20 302 1 Below are parameters for the cycling of settings BOSS Section below is reguired and SettingsSamples must be greater than 1 304 Settings Sampling eio Turns Cycling ONY OFF 30b DoSettingsSampling 0 aiid 4 Number of setting cycles 909 SettingsSamples 4 309 7 Section below is reguired and SampleDuration must be greater or equal to 10 SARROF ROI Parameters Periodi 311 gt Duration of cycle periodl in seconds gt 10 i lea SampleDuration 11 SLs Below you can specify any or no settings to change 314 BkgPDSThreshold 35 Salo ROIThreshold 25 Sos ROIMinSize 4 3L es ROTAspectRatio 900 bak ROTFillRati
120. ify the screws have been completely tightened 16 Figure 6 6 12 shows the completely reassembled pylon ready for aircraft installation SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 142 SPEC CPI Preliminary Technical Manual ae INTERNAL SENSOR oO fe MOUNTED IN PYLON 1 eae at 8 m O Mer PYLON eBoy GSR PYLON cover age et TA CONNECTOR Sie connector F CENTER O RING GROOVE PRECISION MACHINED O RING MATING amp SURFACE Figure 6 6 1 HOLD PYLON COVER AS SHOWN LOWER ONTO PYLON BODY TO ALIGN TONGUE AND GROOVE AND PYLON CONNECTOR Figure 6 6 2 GENTLY LOWER PYLON COVER INTO FINAL POSITION Figure 6 6 3 Figure 6 6 4 gt O oee 2X SHORTER LENGTH FASTENERS Figure 6 6 5 E Figure 6 6 6 _ 715 TORX PLUS DRIVER CENTER PYLON FASTENER SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 143 SPEC CPI Preliminary Technical Manual es am i _ AFTER ALL FASTENERS ARE INTIALLY TIGHT TIGHTEN ALL FASTENERS BY HAND TO FINAL TORQUE THE PYLON COVER IS COMPLETELY MATED TO THE PYLON BODY AND THE O RING IS FULLY COMPRESSED AT THIS POINT Figure 6 6 7 ALIGN NOSE CONE WITH DOWEL PINS AND SLIDE ONTO PYLON DO NOT TWIST WHILE SLIDING INSTALLATION DIRECTION x HEATER
121. ight This section assumes the user has set up the probe per the instructions in the Getting Started Section 2 and is attempting to run the probe The flowchart in Figure 5 2 1 assumes the user has started the CPl exe real time program and is attempting to communicate with the probe by having SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 977 SPEC CPI Preliminary Technical Manual clicked Start Probe in the main window or Apply and Acquire in the Advanced Control and Settings window lf the probe is not working the flowchart will lead to one of four sections 1 RTIA Log Troubleshooting 2 Background Troubleshooting 3 PDS System Troubleshooting 4 Enunciator Troubleshooting If the flowchart does not list an observed problem reading the troubleshooting sections may provide insight and is still suggested Problems with displaying data such as rates and image parameters are not handled here The user is referred to Section 5 1 6 1 Rates and Image Parameters for information on this topic AT THIS TIME THE USER SHOULD BEGIN OPERATING THE PROBE FOLLOWING THE FIGURE 5 2 1 FLOW CHART STEP BY STEP UNTIL THE PROBE IS WORKING BOX IS ARRIVED AT SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 98 SPEC CPI Preliminary Technical Manual D
122. ime and without notice 54 SPEC CPI Preliminary Technical Manual the control voltage times a constant The feedback is set on these drivers so the output voltage will never overdrive the pulse driver All of the laser controllers operating points for the imaging laser current and pulse width values and for the PDS 45 and PDS 90 lasers are set utilizing a quad 12 bit digital to analog converter DAC U40 controlled by the user through the data system graphical user interface GUI 4 2 4 DSP Data Acquisition and Control The sensor electronics are based on a digital signal processor DSP control board that monitors system temperature pressure and voltage and controls 18 heat zones The monitoring and controlling of heat zones are implemented using the relay board piggy backed on the DSP control board Additionally the control board communicates using standard asynchronous serial data protocol using a pair of RS 422 differential signals RS 232 optional by board jumpers with the Data Acquisition System and implements a particle detection system using analog and digital electronics When the data system initially establishes communications with the DSP board it sends a set time Table 4 2 4 packet and a set mode packet Table 4 2 5 The DSP board will subsequently track the time and observe the commanded temperature set points for turning on heaters as well as other commanded parameters such as minimum transit time limits See Table 4
123. indow choosing the Probe tab shown in Figure SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 19 SPEC CPI Preliminary Technical Manual 5 1 8 The time is in units of 20 833 x 10 seconds 1 48 MHz times the raw value The display of the corrected values attempts to display the value in scientific notation however the exponent Is often not viewable In the Advanced control and settings window Figure 5 1 6 a raw value of about 35 counts is a practical value for operation Setting this value too high will prevent the CPI from triggering on smaller particles 5 1 4 Image Collection Control and Monitoring The image processing performed by the DAS is critical in achieving maximum probe performance Just as poor settings in the PDS system can cause the probe to receive no images so can poor settings in the image processing setup parameters cause the probe to process no images even in the presence of high concentrations of particles The DAS takes several steps in order to process images First it takes a background image a frame from the CCD camera with no particles present Then when received camera frames arrive which happens approximately 72 times per second the DAS checks the PDS Status bit to see if the imaging laser was fired during this frame s exposure period If it was the DAS subtracts the frame from the stored background image pixel by pixel
124. insert in the bottom of the case Figure 2 1 13 16 This removable foam insert has been designed to serve as a cushion for the CPI pylon when the pylon is not operational Figure 2 1 14 17 Remove the pylon plug from the CPI sensor head before operating Figure 2 1 15 The pylon plug is used to keep contamination out of the CPI sample tube during shipping It should be reinstalled before the pylon is shipped 18 Verify that the contents of both shipping containers match the contents on the included packing list 19 The CPI can now be connected following the Connection Procedure Section 2 2 Figure 2 1 3 SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 8 SPEC CPI Preliminary Technical Manual Figure 2 1 8 SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 9 SPEC CPI Preliminary Technical Manual PYL lt WHEN REMOVED Ose AYER OF COA IVE LAYER OF FOAM CDEC ACE ec ES c pe ci WoRVEo wor A LIEC Al VY MIC N E Figure 2 1 13 Figure 2 1 14 SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice tO SPEC CPI Preliminary Technical Manual 2 2 Connecting the CPI Sensor Head to the Data Acquisition System Warning Cables MUST be connected in a certain
125. isition System See Figure 2 2 2 CPI Cable Connection Diagram and Figure 2 2 6 Connecting the mouse keyboard power supply screen and sensor AC1 and AC2 6 Connect the 28 VDC Power Cord to the back of the Data Acquisition System See Figure 2 2 7 Connecting 28 VDC to back of Data Acquisition System 7 The CPI is now ready to be powered up SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 11 2 2 2 9 SPEC CPI Preliminary Technical Manual Connection Procedure for Installing the CPI on an Airplane Verify that the Sensor Power switch on the front of the Data Acquisition System is turned off Verify that the Data Acquisition System Computer is turned off See Figure 2 2 1 Front of the Data Acquisition System Connect the Computer Power AC1 and AC2 power cables to a 115 Volt AC source The order of connection of the AC power cables is not important See Figure 2 2 2 CPI Cable Connection Diagram and Figure 2 2 3 Back of the Data Acquisition System Connect the mouse keyboard and monitor to the back of the Data Acquisition System Connect the AcquireNow Hardware Key to the parallel port See Figure 2 2 2 CPI Cable Connection Diagram and Figure 2 2 3 Back of the Data Acquisition System Connect the power dsp cable to J2 on the Data Acquisition System only DO NOT connect the other end to the Sensor Head yet See Figure 2 2 3 Back of the Data A
126. ist of variable power laser drivers for the PDS continuous lasers and bias supplies for the high power imaging laser driver The PDS continuous laser drivers servo the current through the PDS laser diode to force the monitor current to match a level that the digital signal processor DSP sets The maximum current through the laser diodes is limited by a series resistor to the maximum specified for each diode The power level of each laser diode is sensed with the internal monitor diode whose current is converted to a voltage with an instrumentation amplifier U7 U11 This voltage provides negative feedback to the integrator circuit that drives the current drivers driver transistor Q13 or Q14 and driver transistor Q7 or Q10 Each current driver can be configured to source by populating Q10 and Q13 or sink by populating Q7 and Q14 current for their respective lasers allowing for common anode and common cathode devices The default laser is currently a common cathode device from Hitachi the HL7851G a 50 mW 785 nm diode laser The imaging laser flasher a Power Technologies IP40C 20 40 10V is controlled with two supply voltages one sets the forward current the other sets the pulse width These bias voltages are generated with two linear voltage drivers from an on board 60V DC source These drivers U44 integrate until the output voltage equals SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any t
127. it 3 gt Central Sample Tube Bit 4 gt Aft Sample Tube Bit 5 gt Imaging Lens Bit 6 gt APD_45 Amplifier Bit 7 gt APD_90 Amplifier Bit 8 gt Pylon Cover Patch Bit 9 gt Pylon Slug Bit 10 gt Pylon Base Patch Bit 11 gt Imaging Laser Bit 12 gt PDS 45 Laser Bit 13 gt PDS 90 Laser Bit 14 gt Spare DC1 Bit 15 gt Camera 36 Number of detected particles 37 Dead Time Seconds 000341333 38 PDS45 Laser Power Setpoint 0 0073982 Mw 39 PDS45 Threshold Setpoint V 0 000610352 41 PDS90 Laser power Setpoint 0 0073982 mW 41 PDS90 Threshold Setpoint V 0 000610352 42 Imaging laser current control 0 00642700 voltage Setpoint V 43 Imaging laser pulse width 0 007995605 control voltage Setpoint V Minimum transit time sec 20 83e 9 90 APD Amplifier Temp C 1 8775 0 02935559 44 ini itti 45 ifi 46 REF10 2 Vref10 Volts 001464843 Pressure Sensor psi 011014 3 7594 Heater Status 2 Bit Mapped 1 On Bit 0 gt PMT N N CO Bit 1 gt SLS Laser Bit2 gt Unused Bits gt Unused 013736 8775 4 21 308 0 02935559 20 83e 9 J ok i ce 9 50 51 52 54 SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice a9 SPEC CPI Preliminary Technical Manual This equation is only valid for temperatures between OC and 50C Housekeeping values are signed 16 bit i
128. left side on the CPI program window See Figure 2 4 3 SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice Ze SPEC CPI Preliminary Technical Manual an E isi xi Cpi File View Settings Commands Help o me i E III o START 3 Record TAKE Freeze PROBE Eo T Bata ee uale EE serras START PROBE Allocating Memory Please Wait CPI Allocating Memory Please Wait PROBE NOT INITIALIZED INUM ORR m PREE Ce Figure 2 4 3 CPI Program Screen While It Is Allocating Memory l You should see an Allocating Memory message as shown in Figure 2 4 3 This message indicates that the CPI program is allocating memory locally in the Data Acquisition Computer It is not yet trying to communicate with the probe Sensor Head Wait about forty seconds 8 After about forty seconds the message window should change to Initializing the Probe as shown in Figure 2 4 4 In this step the CPI program tries to communicate with the probe If it is successful it sets up probe operating values receives data packets from the probe directs the CCD camera to take two background images and processes those images to establish a background reference for the probe s imaging system After about ten more seconds you should see the CPI startup screen as described in step 9 below SPEC Inc reserves the right to make improvements and chan
129. llecting no useful images Thus a thorough understanding of the user adjustable operating parameters Is a prerequisite to successful use of the CPI The parameters under user control fall into the following categories 1 Particle detection system PDS 2 Image collection 3 Probe thermal control 4 Data acquisition system DAS display The first two categories affect how particle images are collected These include items such as PDS laser power settings and image mean minimums to be discussed in the next section The third category includes the temperature set points of various locations in the probe as well as whether or not heaters should be turned on if the temperature is below the set points in those regions The fourth category doesn t affect the operation of the probe the DAS display parameters only affect how information is presented to the user Each time the CPI DAS program is started the program retrieves information from the CPL ini file This file contains set points set point limits and warning limits for parameters in the first three categories as well as other information of use to the program This file is discussed in the next section Figure 5 1 1 shows the DAS running with an active probe The very top line tells the user that the program is running with recording disabled so no data is written to file The file name of the current file that would be written to if recording were active is also displayed here
130. mages but during this period of no particles the camera s light sensitive surface is never exposed and the images are discarded by the data acquisition system 1 1 2 2 Instrument Behavior With Particle s Present When a particle flies through the instrument and passes through a PDS laser beam some light is scattered forward and around the dump spot by the particle as shown in the cutaway diagram in the upper left of Figure 1 1 3 This light is collected by the PDS photo detector associated with that laser The photo detector converts the light pulse into an analog voltage pulse as shown in red in the PDS waveform diagram in Figure 1 1 3 A comparator 1024 x 1024 Pixels Cropped CP Image a A Waveforms of PDS Detectors Particle Seen Volts Output of Detector N PDS Threshold PDS Detector Output HAR Time SPEC CPI Preliminary Technical Manual Figure 1 1 3 Optics PDS detector waveforms and exposure shot of the CCD camera when the CPI detects a particle in each PDS detector circuit compares the photo detector output voltage with the PDS threshold voltage shown in blue in the waveform diagram in Figure 1 1 3 When the analog voltage pulse from the photo detector exceeds the PDS threshold of the comparator circuit the comparator outputs a clean digital pulse This digital pulse is shown in black in the PDS waveform diagram in Figure 1 1 3 It is passed to a digital logic circuit for processing When a par
131. me and without notice iS SPEC CPI Preliminary Technical Manual ni MOEN DISARMED Time 7 18 File Wem Settings Commands Window Help sto Mt Aed TAKE Freese Aii P Vie l Osa BkGROUND DACON T Doiy ARRAY CLIPPED BY LENS BARREL waa TRIES Psat AEDA ootorteronzr000 Hive video pte Pant ALD sis Figure 6 8 4 SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 154 SPEC CPI Preliminary Technical Manual o s Data Pde 0 07 1 80048Lrot RECORDING O1SAGLED Time 2 08R1 2 58 a File Wen Settings Commands Window Help Lye sTOF r Receed TAKE r Freeee Pee a Soa Figure 6 8 5 Figure 6 8 6 Figure 6 8 7 SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 155 SPEC CPI Preliminary Technical Manual IRDING DISAMLED Time 2 81 e357 EO kea FE Vaid Free pot Pathe 707 PDS 45 LASER BEAM REFLECTING OFF PIN poe DED Mostari o nz10004 H video bottom bp P n E Figure 6 8 8 PDS 90 DETECTOR PDS 45 ba o 3 t 4 P d d DETECTOR da a i IMAGE MIRROR A a _ TILT SCREWS ot IMAGE LENS N FOCUS ADJUST aes Vas A b i A IMAGE MIRROR 1 LOCK SCREW Figure 6 8 9 SPEC Inc reserves the right to make improvements and changes to the CPI and related soft
132. meters that are greyed out or do not display any corrected units in this window are not used for this particular version of CPI Any references to PMT or SLS powers or set points are only used with CPIs containing a Scattered Light System SLS SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice T3 SPEC CPI Preliminary Technical Manual 5 1 3 Particle Detection System Control and Monitoring The upper left section of Figure 1 1 2 of the General Description section 1 1 of this manual shows the major components of the PDS system lasers dump spots and detectors The user adjustable parameters for the PDS system are as follows PDS 45 laser power PDS 90 laser power PDS 45 detector DC level feedback dependent on PDS 45 laser power PDS 90 detector DC level feedback dependent on PDS 90 laser power PDS 45 threshold Voltage PDS 90 threshold Voltage PDS minimum transit time Se Ole lS These items are easily accessed via the Settings window labeled and displayed in the full DAS image Figure 5 1 1 To observe and change items 1 through 4 click on the Lasers tab on the upper right of the Settings window shown in Figure 5 1 7 Items 5 through 7 are easily accessed via the Probe tab of the Settings window shown in Figure 5 1 8 5 1 3 1 PDS Laser Power and DC Level The PDS settings and monitors are contained within the boxes labeled
133. mp AD590 on J2 50 and J2 51 ra Gain Offset9 0 029356 1 877500 0 000000 35000000 LAZ 143 G O10 is the Outside Air Temp AD590 J2 10 and J2 28 power supply 144 Gain Offset10 0 029356 1 877500 0 000000 46 000000 LAS 146 G O11 is the DSP card Temp AD590 J1 2 and J1 41 147 Gain Offset11 0 029356 1 877500 0 000000 60 000000 148 149 G O12 is the PMT Temp Thermistor J2 16 and J2 34 L50 Gain Offset12 0 013736 21 7308 20 000000 507000000 1 Belt 3 L52 G OL3 19 the SLS Laser TMP Thermistor on J2 17 and J2 35 Isie Gain Offsetl3 0 013736 1 877500 40 00000 60000000 154 L554 G 0O14 is the Inside Air TMP AD590 on J2 9 and J2 27 Bosom Gain Offset14 0 029356 1 877500 0 000000 60 000000 cove LOO G 015 is the Camera TMP Thermistor on J2 11 and J2 29 1594 Gain Offset15 0 013736 21 7308 0 000000 397000000 LOO Lola G O16 is the Imaging Laser TMP Thermistor on J2 12 and J2 30 Os Gain OFESSELG 0 013736 215 308 0 000000 35 000000 iG Se 164 G O17 is the PDS45 Laser TMP Thermistor on J2 14 and J2 32 65 4 Gatn 7 Offset l7 0 0137 36 21 7308 0000000 35 000000 lEOs 167 7G 018 is the PDS90 Laser TMP Thermistor on J2 13 and J2 31 166s Gain7Ofiset l 0 013736 2127308 G2 000000 35 000000 L69 EO G O19 is the PDS45 Laser Power J1 22 from photodiode monitor te alle Gain Offset19 0 0246752 1 6774 15 000000 41 000000 SPEC Inc reserves the right to make improvemen
134. mum transit time etc the DSP electronics send a signal to pulse a high power imaging laser and capture an image of the particle on a CCD camera Both PDS systems are functionally identical The PDS systems use a continuous wave laser and beam shaping optics that produce a laser beam with a rectangular cross section The two PDS laser beams are orthogonal to one another forming a volume of approximately 2 5 mm x 2 5 mm x 0 5 mm thick This volume is located in the center of the instrument sample tube tilted at an angle of 45 degrees The rectangular laser beams are dumped onto a dump spot upstream of the PDS detectors Figure 1 1 2 shows the laser beams being dumped in the absence of a particle in the sample volume Figure 1 1 3 is a schematic of the optical system as a particle passes through the sample volume As the particle traverses the PDS laser beams it begins to scatter light around the dump spots and onto the PDS detectors Avalanche photodiodes APDs are used for the PDS detectors due to their ability to detect low light levels The output of the PDS detectors is monitored by the DSP control board The imaging system consists of a CCD camera with an imaging lens and a high power pulsed laser When the DSP electronics receive simultaneous signals from the 45 PDS and 90 PDS detectors to indicate the presence of a particle in the sample volume the CCD camera is exposed with a 20 40 ns laser flash The image of the particle is then
135. must be present for three 48 MHz clock periods 7 Clear Hold Write 0x5000 The HOLD bit in the PDS state machine goes high when a valid particle event the expiration of the transit time threshold in the case of a long duration particle event or an EXTRIG signal comes from the data system computer It forces the state machine to wait until the DSP responds to the interrupt that is generated at the same time the HOLD bit goes active 8 Clear Total Particle Counter Write 0x5001 See item 2 A write to this address clears the counter 9 Clear PDET Bit and IRQO Bit Write 0x5002 See item 3 A write to this address clears the PDET and IRQO bits 10 Trigger Threshold Value Write 0x5005 If written with data bus bit D 11 1 the imaging laser will fire when the transit timer see 1 above reaches the value written at address 0x5005 on the data bus bits D 10 0 D 12 1 forces the PDS state machine in to diagnostic mode where camera frames will be sent to the PC data system no matter what the state of particle events If a PDS channel gets stuck high the state machine will not work in normal operation Setting D 12 1 while writing to this address will bypass that problem Normally D 12 should be set to 0 The DSP controls the PDS trigger thresholds with a 12 bit four output AD5327 Digital to Analog Converter DAC which outputs voltages between 0 and 2 5 V Two other DACS of the same type will be used on the system and all three
136. n extremely cold ambient conditions In this case the user should decrease the lower limit to below 10 C a temperature that the pylon may often reach and that does not require a warning to be issued to the user For the user to have any confidence that the flashing enunciator lights should be taken seriously the limits must be customized in the cpi INI file for a particular CPI in a particular operating environment Other enunciator messages such as PDS Detector Invalid alert the user to a problem with the PDS system If the PDS detector DC level is too high that particular PDS laser power needs to be decreased to allow dynamic range on the detector for triggering see Section 5 1 3 1 This may also indicate a larger problem such as contamination on the windows of the PDS system This condition may indicate it is time for the windows to be cleaned 5 2 CPI Real Time Operation and Troubleshooting The real time operation and troubleshooting section will outline the process of operating the CPI in real time The flowchart in Figure 5 2 1 should be used as a step by step guide to enable the user to operate the CPI in the most efficient manner At certain points in the flow chart depending on the branch taken the user will be referred to troubleshooting information for specific operational problems By using the information in this section the operator will optimize the data collected by the CPI 5 2 1 Operation and Troubleshooting In Fl
137. n probe functionality The higher the threshold is set the more light a particle must scatter in order to exceed the PDS threshold For example if the PDS threshold the blue line in Figure 1 1 3 of the General Description Section 1 of this manual were set greater than the peak that occurs in the figure s red line the AC coupled PDS output the probe would not recognize that a particle had passed through the sample volume and no image of the particle would be produced Because the user is not able to see a waveform of the AC coupled signal and threshold Voltage applied to the detector circuit comparator such as those shown in Figure 1 1 3 the user must become familiar with the effects on the probe of changing the PDS laser power and the PDS thresholds Some other monitored values provide useful information in assessing these effects such as the percentage of valid frames which is shown in the histogram window of Figure 5 1 1 A high percent valid is an indicator that a large percentage of the images captured by the sensor head camera contain in focus particles The possible problem with a high percentage valid however is that the threshold may be set so high that only large particles scatter enough light to cause the PDS threshold to be exceeded thus discriminating against small particles Again this points to the necessity of users familiarizing themselves with the operation of their probe in a laboratory environment prior to engaging in
138. n screen It is best to run live video with recording disabled as approximately 72 full images of approximately 1 Megabyte size each per second will be saved to hard disk if recording is active Live Video Mode is very useful for troubleshooting any image system problems Once live video is turned on the image display will look like Figure 5 1 13 A full frame 1024 x 1024 image of the entire CCD camera though for most CRT and LCD computer monitors only a fraction of the total image may be seen move the scroll bars for the image display area to view different portions of the CCD image will be displayed A red Live Video On message will display in the enunciator panel to indicate live video has been selected The Rates and Image Parameters window see Section 5 1 1 will show the attempted frames per second at 72 and the valid images at 100 The values in the rates and image parameters window will update at the selected update interval The setting of this interval is discussed in Section 5 1 6 2 SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 85 SPEC CPI Preliminary Technical Manual The image mean will be updated in real time in the Img Mean field of the Statistics window of Figure 5 1 13 While running live video adjustment of the imaging laser current pulse width remember to click the Apply button will change the image brightness displa
139. n the DSP_HSKP CPLD The bits are defined as GP 1 General purpose bit going to the SLS board presently undefined GP 2 XMIT HDLC When pulsed high an HDLC transfer is initiated GP 3 7 Undefined GP 8 Heater Enable When high TMRO and TMRI outputs drive the PMT and SLS laser heaters They are disabled at reset in case of DSP failure 5 Set Minimum Transit Time Write 0x4000 A write to this address latches data bus D 0 12 to the TT PDS logic s MT 0 12 bits D 0 11 sets the minimum transit time count that is counted down at 48 MHz Writing a 1 to D 12 enables minimum transit time qualification O disables This comes from the data system but on power up it should be enabled and currently it is with MT 0 11 3 6 Transit Time Qualifier Enable Set Write 0x4000 SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice LFO SPEC CPI Preliminary Technical Manual Writing a 1 to data bus bit D 12 requires the PDS state machine to transit time qualify particle events A down counter is preset to the value written in D 11 0 and counts down using A 48 MHz clock If a particle stops being detected before the counter reaches zero it is not imaged so long as D 12 was written with a value of The state machine defaults to MT 12 MT 12 0 is the registered latch that holds values written to this address 1 MT 11 0 3 Thus by default a particle
140. n the Data Acquisition System to J1 on the sensor Head See Figure 2 2 5 Connecting the sensor camera cable to the Sensor Head Remove the temporary ground wire that was installed in step 5 10 The CPI is now ready to be powered up SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 12 SPEC CPI Preliminary Technical Manual s r F P ek a se i Ok a Shi a tg G i SE OTe Figure 2 2 1 Front of the Data Acquisition System CPI Cable Connection Diagram Sensor Head Front Rear power sensor DSP camera Data Acquisition System J2 Jl J Computer Power d ACI Monitor J ACZ J1 sensor camera J2 power DSP Crouse X Hardware Key Parallel Port Figure 2 2 2 CPI Cable Connection Diagram SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice Re SPEC CPI Preliminary Technical Manual MOUSE J2 SENSOR RS 422 232 SENSOR COMPUTER eee hopr 28 VIDEO CONVERTER FRAME POWER POWER VDC OUT CARD GRABBER KEYBOARD ACQUIRENOW VIDEO HARDWARE CARD KEY Figure 2 2 3 Back of the Data Acquisition System SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 14 SPEC CPI Preliminary Technical Manual iBEE TEE POWER DSP gt Figure 2 2 4 Connecting the power
141. nd without notice 6 SPEC CPI Preliminary Technical Manual 7 Arrival Time 1 333uS periods Number of 1 333uS periods into the current 16 second see 6 at which the particle was detected 8 Transit Time The number of 20 8333 uS periods during which the particle was detected by the APD45 and APD90 sensors 9 Particles Detected Since Last PDS Packet This number includes the current imaged particle for which this packet is sent 10 PDS_45 Pulse Height 16 bit number representing the maximum detected voltage for the imaged particle s on the APD45 Vpx 5V x PDS_45 Pulse Height x 4096 11 PDS 90 Pulse Height 16 bit number representing the maximum detected voltage for the imaged particle s on the APD90 Vpx 5V x PDS_45 Pulse Height x 4096 12 Checksum Word by word checksum over the previous 10 words A housekeeping packet is built and sent to the data system once per second Table 4 2 3 lists the format of this packet Table 4 2 3 Housekeeping packet format Packet Sync 0x4450 Packet Length 51 0 02935559 _ Forward Sample Tube Temp 8775 0 02935559 C i Optics Block A Temp 1 8775 0 02935559 1 Fowar Sani Tbe Tomp Seconds of Year MSW ye 8 Optics Block B Temp C 1 8775 0 02935559 __ i Central Sample Tube Temp 8775 0 02935559 C oO oO Packet Type 0x484b JO oO icin 0 02935559 45 APD Amplifier Temp C Power Supply Temp 1 8775 0 02935559 il
142. neral overview section of this manual In that figure the waveforms of the PDS detector are shown The PDS threshold shown in blue is a DC Voltage applied to a comparator whose other input is an AC coupled version of the PDS detector output either the PDS 45 or PDS 90 detector The threshold Voltage must be set greater than the highest value of the AC coupled signal which has a varying value due to a random noise component During airborne operation the lowest practical threshold value is approximately 200 400 digital counts depending on the noise environment If the threshold is set such that the AC coupled signal may exceed it due to the noise and if both the PDS 45 and PDS 90 channels experience such a threshold exceeding event SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 78 SPEC CPI Preliminary Technical Manual at the same time a false PDS event will occur and the imaging laser will be fired even though no particle is present Another possibility is that of setting the threshold so low that the AC coupled PDS signal always exceeds the threshold in which case the probe will never respond to particles and the imaging laser will never fire From the above paragraph s description of the PDS threshold it is apparent that setting the threshold too low can cause the probe to operate incorrectly Setting the threshold too high can also have negative effects o
143. nnected to the Data Acquisition System unit following the connection procedure 2 Place CPI on stable riser blocks Figure 2 3 1 Height of blocks should be sufficient for bottom connector clearance but low enough to keep instrument stable Figure 2 3 2 3 Plug in vacuum hose adapter to CPI exhaust tube Figure 2 3 3 Vacuum hose adapter may have to be custom fit to mate with CPI exhaust tube Figure 2 3 4 SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice L9 SPEC CPI Preliminary Technical Manual 4 Setup droplet atomizer in front of CPI Figure 2 3 5 The atomizer should spray drops in a direction perpendicular to the direction of airflow into the CPI DO NOT spray drops directly into CPI along flow direction See Figure 2 3 6 Water drops will contaminate the windows and the windows will need to be cleaned 5 Power on the data system and probe per the CPI startup procedure Section 2 4 and run CPl exe program 6 After the CPI program has successfully started and obtained a background turn on vacuum cleaner and spray water drops by squeezing atomizer bulb The CPI program should show water drops appearing in real time If the vacuum is turned on before the CPI has obtained a background it may take longer for the CPI to obtain a background due to particles passing through the sample volume Figure 2 3 1 Figure 2 3 2 VACUUM HOSE INSERTED INTO C
144. notice oO SPEC CPI Preliminary Technical Manual sec Arrival time of 1 3333 us periods into 16th C 8 _ Transittime _ o Oo Z o a Particles detected since last PDS packet PDS_45 pulse height PDS_90 pulse height Checksum _ o Checksum Table 4 2 2 PDS with SLS packet format ord 1 Packet Sync Word 0x4450 2 Packet Length 10 3 Packet Type 0x5051 4 UTC Seconds of Year LSW 5 UTC Seconds of Year MSW 7 10 11 28 Arrival time of 1 3333 us periods into 16th Particles detected since last PDS packet PDS_45 pulse height A 2 l C 4 5 Arrival time of 62 5 ms periods into sec a 10 11 PDS_90 pulse height 12 27 SLS pulse heights 16 28 Checksum The PDS packet fields are described below 1 Packet Sync Word Used by the data system to detect the beginning of a packet 2 Packet Length The number of words in this packet 12 3 Packet Type PDS packet with no SLS system is defined 0x5050 4 UTC LSW Universal Time Code least significant word This and word 5 the most significant word combine to give the number of seconds since the beginning of the current year 5 UTC MSW Defined in 4 6 Arrival Time 16ths Number of 62 5 millisecond periods elapsed into the current second see 4 and 5 at which the particle was detected SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time a
145. nt in the image If the probe is repeatedly trying to take a background and is in high concentrations the solution is to exit the cloud for a brief period to allow the probe to take a background image in clear air Particle Threshold Too Low Minimum Size Pixels Too Low The Particle Threshold and Min Size Pixels fields in Figure 5 2 3 greatly affect whether or not the DAS detects particles real or not in image frames If the probe is failing to get a background try changing these values to the more conservative values of 50 for the Particle Threshold and 6 for the Min Size Pixels If this is not the problem the user should go back to the previous settings somewhere around 40 and 4 as raising these values raises the minimum size particle the probe will measure See Section 5 1 4 2 Particle Collection and Associated Controls for more information on the Particle Threshold and Min Size Pixels settings Image Mean Too High Too Low Each CPI has a different range of image means with which it performs well A reasonable range for most probes however is 80 to 160 These limits are entered by the user in the Advanced Control and SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 103 SPEC CPI Preliminary Technical Manual Settings window a portion of which is shown in Figure 5 2 4 and which comes from the b
146. ntegers and the values of each parameter are solved from Housekeeping Value CO C1 x Raw where Raw is the 16 bit signed value sent in the housekeeping packet The CPI accepts four control packets that allow the data system to set various parameters and to control the data flow Table 4 2 4 lists the format of the set time packet and Table 4 2 5 lists the format of the set mode packet Table 4 2 4 Set Time Packet Format Packet sync 0x4450 Word 2 PacketLength 6 4 Time MSW 5 Time LSW 6 Checksum Table 4 2 5 Set Mode Packet Format Packet Sync Word 0x4450 Packet Length 26 Packet Type 0x4d44 4 Probe Mode Bit Mapped 1 Bit O set gt De ice Heat on Bit 1 set gt Unused Bit 2 gt Reset probe Bit 3 gt 1 equals enable the imaging laser trigger timer threshold feature see word 35 Bit 4 gt 1 equals enable diagnostic mode for diagnostics only should be hard to set Bits 5 7 gt Unused SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 60 SPEC CPI Preliminary Technical Manual Bits8 15 Command Heater Status Bit Mapped 1 on 1 Bit 0 gt Forward Sample Tube Bit 1 gt Upper Optics Block Bit 2 gt Lower Optics Block Bit 3 gt Central Sample Tube Bit 4 gt Aft Sample Tube Bit 5 gt Imaging Lens Bit 6 gt APD_45 Amplifier Bit 7 gt APD_90 Amplifier Bit 8 gt
147. nual as shown in the Figure 5 1 3 Parameters that do not display any corrected units in the housekeeping window are not used for that particular version of CPI Any references to PMT or SLS powers or set points are only used with CPIs containing a Scattered Light System SLS SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 68 SPEC CPI Preliminary Technical Manual f jol Raw Corrected p eget ectelsees a Forward Sample Tube Temp Probe Time 2 10 15 13 30 Laser Strobes 0 Heater Status Probe HouseKeeping Data Lle kx Optical Block amp Temp Optical Block B Temp 20 5 deg C Central Sample Tube Temp 20 deg L ft Sample Tube Temp Forward Sample Tube Optical Block 4 Optical Block B Pylon Base Patch Temp a Hii Camera Filter Temp 1 9 deg L 927 29 1 deg C ofe 27 5 deg L gar 29 1 deg C 2048 6 4 deg C Pylon Base Patch iia 26 4 deg E Imaging Lens Inside Air Temp ar 2r 4 degC Spare _OL 437 26 4 deg L ie 332 26 3 degC SLS Laser 436 off degC 435 off deg PO Amplifier Temp Central Sample Tube Att Sample Tube Pilon Cover Patch Pilon Slug a sls wn 2 m ee Oe oe Oo oa oo we eu S 1 re NHE 5 Pla Oy DO Ss 0 o Oo 3 o on os ig 3 tt S SS eal sd ele amp om o o o ae a oy oy a 0 a ao 3 3 3 2 ojoj 0 90
148. number is displayed Skips in the frame number are a result of no ROI s found in the frames skipped CCD X Y BACKGROUND FRAME LOCATION IN ROI ARRIVAL TIME FRAME NUMBER PIXELS ROI SIZE ROI IN MICRONS FST TUE F20 39295 T t 791 632 95235 me 9 27 34 20 i 34 Bkg 0 0 2328x2328 TTO 613 566 39 33 Time 2 OT R4 57R Big 0 0 232622326 Tise 14 53 21 716 TTE 143 520 44 44 Time 9 27 R4 598 T 2 169 626 30 30 Ties 9 9 24 89 Figure 5 1 16 Close up of ROI display boxes The second set of controls in Figure 5 1 15 are for the Particle Size Histogram display The histogram plots the number of particles in a given size bin against a number of size bins chosen by the user as seen in Figure 5 1 17 If the Plot it box is checked the histogram will activate the first time a ROI is found The particle size range and the number of bins are entered in the Settings Disp Hist window in the Min and Max size bin text boxes and in the Bins selection box SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 20 SPEC CPI Preliminary Technical Manual Ea Fla a Particle Histogram Farticle Total 168 Particle Total 78 6 10 441g 210 Ww 10 5810 26100 at1Q0 2 10 BD O M fe A moo w ety a aa TS ee ee gt i DANADOS NUA Q M oo oO O nh ha ppa
149. o 0 000006 Slo ROIXPad 6 320 ROIYPad 6 Sal Probe Settings Periodi Sa Probe Settings values for Period 1 CAET These are optional 324 PDS45 Threshold SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 167 SPEC CPI Preliminary Technical Manual S22 Settingl6 800 JAO PDS9YO Threshold Cer ie Settingl7 800 328 ROI Parameters Period2 EPAM SampleDuration 12 5 330 ROIThreshold 45 Badis ROIXPad 14 SO ROIYPad 14 25 Probe Settings Period2 334 Settingl6 600 Seer Settingl7 601 556 ROI Parameters Period3 SOL SampleDuration 10 5 338a ROIThreshold 55 EDEN ROIXPad 10 340 ROIYPad 10 341 Probe Settings Period3 342 Settingl6 700 343 Settingl7 701 344 ROI Parameters Period4 345 SampleDuration 10 5 346 ROIThreshold 65 347 ROIXPad 10 348 ROLY Pad 10 349 Probe Settings Period4 S501 Settingl6 800 Seo les Setting1l7 801 7 3 DSP Memory Address Decodes and Heater Controls A Programmable Logic Device PLD U3 decodes the DSP s external data memory for the CPI as described in Table 7 3 1 Table 7 3 1 DSP Memory Map Size words 0x2000 Housekeeping ADC AD7878 0x2001 2 R AD7878 Status Read SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 168 SPEC CPI Preliminary Technical Manual Ox2002 2 Housekeeping Control R
150. o 2047 The power and voltage set points are in the range of 0 to 4095 In either case the engineering unit EU for a particular parameter is calculated with the following equation EU Co C1 Set Point The probe mode is returned in the housekeeping so that bits 8 15 of word 4 which contain the command number can be used to hold a unique number thereby providing the mechanism for verifying that a set mode packet has been accepted 4 2 5 Power Supply Board see the schematic in Appendix 7 1 This board generates four DC voltages using 28V DC that comes from the Data Acquisition System The generated DC Voltages are 15V 15V 7V and 7V Many of these are converted using linear regulators at the DSP board to create the most noise free DC supplies possible The DSP board also has an on board DC DC converter to generate a 60V signal used in the bias circuits for the imaging laser discussed previously SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 62 SPEC CPI Preliminary Technical Manual 5 0 SOFTWARE DESCRIPTION AND REAL TIME OPERATION 5 1 Data System Overview The SPEC CPI data acquisition system DAS and its settings are as important to the collection of high quality data as is the correct operation of the electronics Were the electronics working perfectly but the DAS settings adjusted incorrectly the instrument could go an entire flight co
151. o turn off the imaging laser level control algorithm so that the real time software lets the user maintain control leave the Enable Mean Error Event checkbox unchecked Even if the checkbox is left unchecked the background minimum and maximum values for acceptable background image means is entered in this form and must be set correctly SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 116 SPEC CPI Preliminary Technical Manual Under user control the image mean min and max set in the Settings Advanced Control and Settings window see Section 5 2 3 2 defined the acceptable range of the background mean However under Al algorithm control the background mean s range must also be entered in the form shown in Figure 5 3 3 and the background mean s range should be tighter than the image mean s range In other words the Minimum Mean in the Al form Figure 5 3 3 should be larger than the minimum image mean in the Advanced Control and Settings Window Also the Maximum Mean in the Al form Figure 5 3 3 should be smaller than the maximum image mean in the Advanced Control and Settings Window A good starting point for the Al algorithm settings is Minimum Mean 130 and Maximum Mean 150 Pulse Width Update Step how many counts to adjust the laser pulse width setting 100 is a good value here Maximum ROls in Diff image If there are more
152. or this on line 66 of the cpi INI file are again given in ADC values Setting14 4095 0 4095 And the reported limits on line 171 Gain Offset19 0 0246752 1 6774 15 000000 41 000000 are 15 and 41 mW upper and lower respectively The settings and gains offsets all have a descriptive line of text above them indicating which physical parameter the values correspond to Other than the settings limits and alarm limits the user should not manipulate anything in the cpi INI file The limits are set to reasonable values by SPEC before shipping the CPI and data system however some changes to these values may be appropriate depending on operating conditions See Section 5 1 7 1 Finally a few setting limits and gain offset limit values are set at the factory and should not be changed They are 1 Imaging laser current set voltage 2 Imaging laser pulse width set voltage 3 Imaging Laser Current Set Point 4 Imaging Laser Pulse Width Set Point 5 1 7 1 Enunciator Panel The purpose of the enunciator panel is to alert CPI operators to potential instrument problems Figure 5 1 19 shows the enunciator panel that is located at the top of main real time operation window in Figure 5 1 1 Ideally the user sees a clean panel during normal operation That is only a green background valid light is present The other lights alert the user to some problem conditions for normal operation Recording Disabled tells the user that no d
153. or the PI algorithm the difference equation implemented is uk uk 1 Kp Ki T ek Ki T Kp ek 1 In this equation uk is the applied DC laser setting as the user would enter in the Settings Advanced Control and Settings form uk 1 is the previously applied value ek 1 is the error between the desired laser DC voltage and the previously measured DC voltage The larger this number Ki T the faster things change but you get less stability Ki T should be greater than Kp twice Kp is a good start Adaptation Parameter Kp See above Maximum Iterations After this number of iterations if the set level isn t within Err Thresh Stop Change Volts of the DC set point the algorithm looks for a stable state again and starts over 5 3 3 PDS Threshold Control PDS thresholds affect the sensitivity of the CPI Users balance the desire to see the smallest particles corresponding to lowest threshold settings with getting empty images caused by the probe interpreting electronic or optical noise as a particle event The artificial intelligence Al code added to the real time software attempts to do the same thing using the following algorithm 1 Raise PDS threshold by X4 start with X4 50 If the following two conditions are met a The number of laser flashes per second is gt X1 for X2 seconds start with X1 5 and X2 5 b R lt X3 0 1 to start for the same period of X2 seconds where R number of valid frames number of strob
154. orithm to identify a dust particle stuck to the lens even if its image moves around a little from frame to frame An Overlap ROIs pixel offset value of 1 means EXACT overlap SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 115 SPEC CPI Preliminary Technical Manual P1 X1L Y 1 ROI 1 P2 X2 Y2 Q2 X4 Y4 Figure 5 3 4 Calculation of Overlap ROIs Pixel Offsets Max Consecutive Frames Checked Number of frames that must have overlapping particles to execute new background Overlapped ROI count limit Need more than this value to execute background Leave at 0 to remove all stuck images 5 3 5 Laser Pulse Width Control The imaging laser energy incident on the CPI s digital camera sensor is proportional to the image mean or how light the exposed image appears If the energy is too low then the exposure is too dark to see particles too high and saturation nets the same effect Users can set this incident energy by changing the imaging laser current setting and the imaging laser pulse width setting It is standard practice with the CPI to set the imaging laser current to its maximum 4095 counts then adjust the pulse width to achieve an optimum image A new Al control does the same thing changing the imaging laser pulse width to maintain an optimal image mean The upper half of the form shown in Figure 5 3 3 controls this new Al feature T
155. ors captive to the pylon Figure 6 3 4 If the pylon is connected to the data system as is the case when installed on an aircraft make sure that both the base and full cables are removed before J20S J218 or J22S 8 Using a small flat blade screwdriver loosen the screws for connector J20S AC power and J21S DC power Figure 6 3 5 These screws are captive to the connectors Using the 3 32 ball driver remove the screws and lock washers for connector J22S DSP data 9 De mate connectors J20S J21S and J22S from each of their mating connectors captive to the pylon Verify that five connectors have been completely de mated at this point 10 2X 8 32 Torx plus fasteners are used to lock the aft sample tube into the correct position Figure 6 3 7 Using the T15 Torx plus driver remove the two fasteners for the aft sample tube Figure 6 3 8 11 The CPI pulling fork tool is required to assist in the internal sensor removal Figure 6 3 9 shows the CPI pulling fork tool and the pry points on the aft sample tube and pylon 12 Study Figure 6 3 9 thru Figure 6 3 22 before proceeding any further 13 Slide the slots in the pulling fork over the aft sample tube pry bosses and the pylon pry bosses Figure 6 3 10 14 Gradually pull back on the pulling fork in the direction shown in Figure 6 3 11 to begin removal of the aft sample tube As the aft sample tube begins to slide the internal sensor head will also begin to slide off the inlet
156. orter fasteners are marked in black below the screw head Do not install 3 4 fasteners in these two locations or the pylon will be damaged 9 Install the remaining 20 fasteners in the proper locations Using the T15 torx plus driver engage all the fasteners but do not tighten completely As the various fasteners are engaged verify the pylon cover remains aligned to the pylon body Figure 6 6 6 10 After all the pylon fasteners have been engaged begin the process of completely tightening each of the fasteners Figure 6 6 7 The gap between the pylon cover and body will be completely closed as the cover is tightened down Do not use excessive force on the fasteners as they may break It will be obvious when the fasteners are completely tight because they will be much harder to turn 11 Verify all fasteners are completely tightened The ones initially tightened may require additional tightening after all fasteners are completely installed 12 Prepare to install the inlet nose cone onto the pylon as shown in Figure 6 6 8 It is very important that the alignment pins mate correctly 13 Align the pins and press the nose cone onto the pylon as shown in Figure 6 6 9 The nose cone should completely engage onto the pylon if aligned correctly 14 4X 6 32 socket head cap screws are used to mount the nose cone to the pylon Figure 6 6 10 15 Install and tighten the mount screws using a 7 64 ball driver as shown in Figure 6 6 11 Ver
157. ottom center of the full window Image Processing Options Secondary Video Display Options Threshold 40 2 Image Display Mode ROl Pad E No Image Display Poly Pad E i Raw Images Full Background Subtracted E Em Fei Frm E C Background Images Generate PDS Triggers Display Image Information ROI Rejection Criteria For Each Image P Pre Set Rill Debug Periodic Statistics Min size Pixels 4 Background Options Fii Ratio 72 be 00E 640 2 Update Background Now Bkground Rate secs e0 Max PDS Rate fio Figure 5 2 4 Background acquisition parameters in the Advanced Control and Settings window Aspect Ratio gt 1 Min Img Mean In Figure 5 2 4 the minimum and maximum image mean are set to 2 and 255 respectively which is so large a range as to allow image means below and above desired operating limits This is useful for diagnosing the image mean when the probe is failing to take a background or for running live video If these limits are tighter than the current image mean of received CCD frames both live video and background acquisitions will fail so a wide range is useful for troubleshooting however once the retrieved image mean has been adjusted to desired levels the user should set the limits to 80 and 160 for the Min Img Mean and Max Img Mean fields respectively Once changed as with all fields in the Advanced Control and Settings Menu the u
158. out notice 130 SPEC CPI Preliminary Technical Manual MIRROR SUPPORT FOOT o Figure 6 3 23 6 4 CPI Internal Sensor Running On Test Stand The CPI internal sensor should be mounted to the test stand when it is operated in the laboratory out of the pylon This procedure describes how to mount the internal sensor to the test stand and connect the test cables Proper ESD precautions should be taken while connecting the test cables and operating the instrument Warning The CPI internal sensor head is a high performance assembly that consists of many optical components electro optics assemblies and ESD sensitive electronics The pylon serves as a protective housing for the internal sensor head When the internal sensor head is removed from the pylon the optics are no longer protected from contamination The internal sensor head should be worked on in a dust free ESD protected environment after removal Installation of the internal sensor onto the test stand should only be performed by personnel who have read and become familiar with this procedure 1 Figure 6 4 1 shows the CPI test stand and the internal sensor on an ESD safe surface The green handles shown in Figure 6 4 1 should be used to handle the internal sensor 2 Figure 6 4 2 shows the location of alignment sensitive optical components Care should be taken not to bump or disturb these components when working with the internal sensor removed from the pylon 3 Using th
159. pped cut out from the image frame The ROIs are cropped from the picture and stored into the current data file on the hard disk This keep the data files as small and compact as possible The data file has the file extension ROI A PDS data packet will be associated with each ROI in the data file The PDS packet is sent from the DSP to the Data Acquisition System via the RS422 link It contains information such as the particle s arrival time and the peak heights of the two PDS signals for the laser trigger event associated with this particle see the data acquisition system section for full details of the PDS packet SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 6 SPEC CPI Preliminary Technical Manual 2 0 GETTING STARTED 2 1 Unpacking the CPI System This procedure is to be followed when unpacking the CPI system after shipment or storage Open the container containing the CPI data system and other accessories Figure 2 1 1 Remove the flat panel monitor manuals mouse keyboard cleaning tool alignment pin and pulling fork from the case Figure 2 1 2 Remove the top layer of foam exposing the data system and accessories Remove the data system AcquireNow hardware key power cables monitor stand test stand and atomizer from the case Figure 2 1 3 The atomizer and alignment pin should be wrapped in bubble wrap Foam blocks have been inse
160. procedure in Cleaning Windows Section 6 7 5 2 4 2 What To Do If the PDS Threshold Needs Adjustment The PDS threshold settings are adjusted in the Probe tab of the Settings window shown in Figure 5 2 3 200 is a normal lower limit though some probes can be operated at even lower values while running in a laboratory such as the 167 value shown in Figure 5 2 3 As described in the Particle Detection System Control and Monitoring Section 5 1 3 the higher the threshold is set the fewer small particles are seen 600 is a nominal upper limit however like the lower limit this is not a hard and fast number If the probe is not collecting particles and the PDS laser power levels are acceptable adjust the PDS threshold to a safe value 350 and click the Apply button At this setting particles of the smallest size may not be seen but if in the presence of an ensemble of cloud particles that includes some medium 50 to 100 um to larger particles this setting should be safely above the noise and allow the PDS system to detect particles However if particles are still not collected lower values should be attempted 5 2 4 3 What To Do If the PDS Minimum Transit Time Needs Adjusting As described in the optics section of the manual the PDS sample volume is 0 5mm thick and tilted at an angle of 45 to the direction of particle travel The time required for a particle to enter then exit the sample volume is ignoring the
161. puter Referring to Figure 4 2 3 Once the image download is complete the frame grabber interrupts the computer with a FRAME INTERRUPT signal and the CPI software checks the PDS STATUS bit to see if the imaging laser was fired If it was not then the PDS STATUS bit is a logic zero and the image frame is discarded If it was then the PDS STATUS bit is a logic one and the image frame is searched for regions of interest ROIs locations in the image where particles are present The ROls are effectively cut out of the picture and stored into the current data file the name of which is based on the data system computer time when the file was started with the file extension ROI Also associated with each ROI in this file will be a PDS packet containing information such as arrival time and peak heights of the PDS 45 and PDS 90 signals for the laser trigger event that captured the particle image The PDS packet is sent from the DSP to the data acquisition system via the RS422 link Returning to the timing diagram of Figure 4 2 3 the 1st EXSYNC pulse from the frame grabber to the Basler camera and the DSP board starts the camera downloading IMAGE 1 to the frame grabber When the data transfer completes the data system computer gets a FRAME INTERRUPT from the frame grabber associated with IMAGE 1 and sees there are no PDS packets to look for because PDS STATUS was low during EXSYNC1 IMAGE 1 is discarded The laser has been triggered during the transfer of I
162. pylon cover it is first necessary to remove the nose cone Using a 7 64 ball driver or hex wrench remove the four screws mounting the nose cone to the pylon Figure 6 1 3 5 Do not twist the nose cone during removal After the four screws are completely loose remove the nose cone from the pylon by pulling away from the pylon Do not twist the nose cone as you pull This procedure is shown in Figure 6 1 4 Put the nose cone in a safe place taking care not to damage any sharp edges The nose cone contains two de ice slug heaters a temperature sensor SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 118 SPEC CPI Preliminary Technical Manual and connector Figure 6 1 5 Dowel pins are used to properly align the connector to mate correctly 6 Torx plus fasteners are used to fasten the pylon lid to the pylon body This type of fastener uses a special type of drive to minimize stripping of the drive head over repeated use Special T15 Torx Plus drivers Figure 6 1 6 are necessary to work on the pylon These drivers have been provided with the CPI 7 21X 8 32 Torx plus fasteners are used to fasten the pylon cover to the pylon body 19 of the fasteners are 3 4 long while 2 of the fasteners are only 72 long Figure 6 1 7 The locations of the 72 fasteners are important during reassembly of the pylon cover 8 Using the Torx plus driver gradually loo
163. rameters are out of range such as temperature readings or other items that the user should be aware of and possibly take action on The image display section shown in Figure 5 1 1 contains regions of interest ROIs cut outs This is where particles will be displayed as they are processed by the DAS The statistics and settings windows are another set of quick observation and control windows in which the user can view and control various parameters that are also available in other menus but are easily accessed here The settings window can be opened if not currently open by clicking the Settings button on the quick access line discussed in the previous paragraph The Rates and Image Parameters window plots various real time parameters to inform the user of probe performance such as the displayed frames per second plotted in red the percent of valid frames in green Detailed descriptions of all the data system menus and displays including the above items are given in the following sections System menu windows will first be generally described then the operation of the probe and DAS using the categories of parameters under user control will be detailed PDS system image collection system probe thermal control and DAS display 5 1 1 View Menu sie Data File B 02101434 roi RECORDING DISAB File View Settings Commands Window Help Housekeeping SPP1OO Data Single Board Computer Serial Data Stats Win
164. rted into the computer case for added protection during shipping Remove the three screws for the computer cover Figure 2 1 4 and remove the computer cover Remove the foam blocks from inside the computer Figure 2 1 5 Taking proper ESD precautions inspect the components inside the computer Check that all the computer cards and chips are properly seated and that all cables are connected for disk drives etc After a visual inspection that nothing was damaged in shipping reinstall the computer cover The data system is shipped with the AcquireNow hardware key removed and the captive cabling unplugged Figure 2 1 6 Connect the AcquireNow hardware key and the captive connectors to the RS 422 232 converter card as shown in Figure 2 1 7 Open the shipping case containing the CPI sensor head and cables Figure 2 1 8 Remove the cables from the top layer of foam both the test cables and standard cables are contained in this box Figure 2 1 9 Remove the top layer of foam Figure 2 1 10 This foam insert has been designed to use as a cushion for the pylon cover and nose cone during disassembly of these components Figure 2 1 11 Set this layer of foam aside for now Remove the CPI pylon from the shipping case Figure 2 1 12 SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 1 SPEC CPI Preliminary Technical Manual 15 Remove the foam
165. ructure BlockNum 0 Header Block Marker Ver o Versionnumber ofthis frame o ROKCount 0 umber of ROTSinthisframe day imeota OOOO hor o fimeotfame023 OOOO minte oB meotfame059 OOOO O se imeottameos9 OOOO me o imeottame0999 OOS S metye 0 bitaray with data information o o o soo o upperteft Xcomerofimge O OOOO so o upperteft comerofimge oooO Ex fo lowerright X comer ofimage SSS Fy o lowerright Y comer ofimae O BGRate time between backgrounds in tenths of a second 0 means no bckgnds BkgPDSThresh O number of machine strobes before a background can be collected total number of frames processed so far SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice ie Ss SPEC CPI Preliminary Technical Manual Tihesh 0B Image threshold 0 255 O means no thresholding done ROIE 0B ROIRejection Fallure code ROIMinSize 0 minparticleejectionsize o ROIAspect 00 particleaspecteriteria SSS ROI 00 min value for pixels within ROT threshold pixels in ROD imgMean 0B _ imagemeanvalue SSS BkeMean 0B background mean vle SSS Spare 0 Ums OO o o ROIXPad 0 width of border around sides of particle in pixe ROIYPad 0 width of border around top bottom of particle in pixels TmgMinVal 0B min image mean for an acceptable frame TmeMaxVal 0B max image mean for an acceptable frame CkSum o esm OOO PDSHead INTA
166. s copied from a rtialog txt file taken when that error occurred 5 2 2 1 Sensor Head Powered Off Camera Connector Disconnected Trying to start communicating with the probe while the sensor head is powered off is a common mistake Fortunately it is easy to diagnose See Figure 2 2 1 of the Connecting the CPI Sensor Head to the Data Acquisition System Section 2 2 Locate the sensor power indicator and see that it is lit if not turn on the sensor power switch lf the sensor power is off the rtialog txt file will have lines in it that match the following OJPCLNKCapture m_CaptureStartingEvent Set PCLNKCapture PCD_SWTRIG1_32 SENT Frame TIMEOUT PCLNKCapture PCD_SWTRIG1_32 SENT Frame TIMEOUT PCLNKCapture PCD_SWTRIG1_32 SENT Frame TIMEOUT If these repeating lines are found in the log file check the sensor head power is on as described If the power Is on another cause of these lines in the log file is the data acquisition system DAS computer to sensor head camera connector being disconnected See Figures 2 2 3 and 2 2 5 for the J1 sensor camera connector locations on the DAS and sensor head in the Connecting the CPI Sensor Head to the Data Acquisition System Section 2 2 5 2 2 2 No Hardware Key Connected The CPI software requires that a hardware key be connected to the parallel port of the computer If there is nothing plugged into the parallel port the rtialog txt file will produce the following CTracer Fin
167. s of Voltage It indicates the steady state average of the PDS detector outputs The PDS detector has an output voltage maximum of approximately 9 6V and the DC level must be below this to provide dynamic range for the detector to respond to incoming particles The DC level during periods when no particles are being detected for a second or more is an indication of how much light from the laser is making its way past the dump spot and on to the PDS detector If the detector DC level goes above 8 8V there is not enough dynamic range for the PDS system to sense a particle and the system may not record particle images even though particles may be present In this case the enunciator indicators will flash red and indicate that the PDS 45 or PDS 90 detector DC level is out of range The user should decrease the associated laser power to get the DC level to below 8 8V SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice z SPEC CPI Preliminary Technical Manual 5 1 3 2 PDS Threshold Control The PDS 45 and PDS 90 thresholds are easily monitored in the Probe tab of the Settings window shown in Figure 5 1 8 ex rea c a PDS30 heer pr E7 B Ulisse j Background Options Bkground Aate secs 60 z Strobes Threshold 10 HEATERS APPLY Figure 5 1 8 Probe tab of the Settings window To understand the threshold setting refer back to Figure 1 1 2 of the ge
168. sed to 4 or greater the above two images would be considered a valid background Two realistic values for these parameters are 36 for the particle threshold and 4 for the minimum pixel size Using these values IMAGE 1 would possibly be accepted as a valid background Once it is determined there are no particles in the potential background image the average of the pixel values is taken For IMAGE 1 the value would be 118 8 This value is then compared with an acceptable range entered by the user Min Img Mean and Max Img Mean Figure 5 1 11 shows these parameters entered in the Advanced Control and Settings Panel The values 2 and 259 shown in the figure are not a normal range as it allows almost any image to be accepted since each pixel has a value range of 0 to 255 usually the minimum value is on the order of 70 and the maximum value on the order of 180 If such were the range our IMAGE 1 mean of 118 8 would be acceptable and IMAGE 1 would be stored as the current background Background images are taken almost immediately after the probe is started No particle images are processed until a valid background is acquired apparent to the user via a green enunciator SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice SZ SPEC CPI Preliminary Technical Manual declaring Background Valid as seen in Figure 5 1 1 The probe also takes backgrounds at r
169. sen all the pylon fasteners approximately 1 4 to turn saving the center fastener for last Figure 6 1 8 This will gradually decrease the compression on the O ring and uniformly decrease the stress on the pylon cover Once all the fasteners have been initially loosened proceed to remove them until all 21 fasteners are removed Place the fasteners in a safe place as they will be reused during reassembly 9 Two pry points are located on the pylon cover to facilitate removal Figure 6 1 9 The pylon cover mates onto the pylon body with a tongue and groove design 10 Verify that all 21 fasteners have been removed form the pylon cover Insert a small flat blade screwdriver into one of the pry grooves Figure 6 1 10 and gradually pry upward on the pylon cover Take care not to damage the tongue or O ring on the pylon cover Very little force should be required to lift the tongue on the pylon cover from the groove on the pylon body 11 After the cover has been freed from groove grasp the cover with two hands as shown in Figure 6 1 11 12 Lift the cover directly upward to until it clears the internal sensor head assembly Figure 6 1 12 13 Place the cover in a safe location such as a soft foam surface Figure 6 1 13 14 Figures 6 1 14 and 6 1 15 show the parts of the pylon cover and pylon body that mate together Inspect the O rings for wear that may occur over time If the O rings appear damaged they should be replaced SPEC Inc r
170. ser must click the Apply button which may also say Apply and Acquire else the DAS won t use the new values Note that also the background mean limits must be changed in the Al background control window shown here in Figure 5 2 5 and discussed in detail in the Laser Pulse Width Control Section 5 3 5 These limits must be tighter the minimum mean greater than or equal the maximum mean less than or equal to respectively than the image mean settings in Figure 5 2 4 To open the limits of the image mean for live video only the Min Img Mean and Max Img Mean values in Figure 5 2 4 need to be changed If the image mean needs to be raised or lowered the imaging laser is adjusted to bring the image mean to a desired level The adjustment is easily made in the Lasers tab of the Settings window shown in Figure 5 2 6 Make sure the Laser Current Set Point is at or near its maximum 4095 then adjust the Pulse Width Set Point up to get a higher image mean or down for a lower image mean SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 104 SPEC CPI Preliminary Technical Manual Background Image Control and Adaptation Settings Figure 5 2 5 Al Background control chosen from the Settings menu SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without noti
171. ser that the mean of the CCD camera image was 9 but the acceptable range is 63 to 195 In this case the imaging laser power might have been turned down and needs to be adjusted back up If the line read BAD Mean 220 the imaging laser would need to be turned down See Section 5 2 3 2 What To Do If Probe Is Communicating With DAS but No Background Taken which describes how to adjust the image mean 9 2 3 Background Troubleshooting The background collection process and the parameters affecting it are described in detail in Section 5 1 4 1 Background Images and Parameters The first thing the DAS must do on start up is acquire a background from the sensor head CCD camera The various problems that can occur in taking a background are described in the following sections The flowchart of Figure 5 2 2 provides a guide to steps for correcting background problems 5 2 3 1 What To Do If No Background Is Acquired At Startup see flowcharts of Figure 5 2 1 and Figure 5 2 2 SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice KO SPEC CPI Preliminary Technical Manual No Did probe initialize Correctly See flowchart In Figure 5 2 1 Yes Is the Failed To Get a Background enunciator active No Enjoy the flight your probe Yes is working Are the Image mean MIN MAX and Background Mean MINS MAX Setto
172. serves the right to make improvements and changes to the CPI and related software at any time and without notice 93 SPEC CPI Preliminary Technical Manual Item 1 is automatically changed from within the CPl exe program so should not be manipulated here The value of these three items is given in analog to digital conversion ADC raw numbers they are not actual engineering units Understanding how to interpret and set these numbers requires looking further into the file The next section of the file with heading Gains Offsets for Readings contains on lines 116 and 117 Gain offseti is the Forward Sample Tube Temperature A4DS590 on J2 1 and J2 19 Gain Offsett oe 1 677500 10 000000 35 000000 Gain wer Alarm Upper Alarm Offset i Limit Limit Again note that the semicolon indicates that the information on line 116 is for the users information only the DAS does not do anything with it The next line contains values described from left to right Gain Offset Lower Alarm Limit Upper Alarm Limit AY The gain and offset are applied to measured Analog to Digital Converter ADC values For example if the ADC is read for the Forward Sample Tube and is determined to be 800 the temperature in degrees Centigrade would be found Forward Sample Tube Temp ADC x Gain Offset Forward Sample Tube Temp 800 x 0 029356 1 8775 Forward Sample Tube Temp 25 36 C The alarm limits are given in engineering units degrees Centigrade
173. sor Head Thermal Control The probe sensor head has 12 temperature zones it controls all with set point controls in the Advanced Control and Settings window of Figure 5 1 6 The name for the 12 heat zones is given here for reference SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 86 SPEC CPI Preliminary Technical Manual Forward Sample Tube Optical Block A Optical Block B Central Sample Tube Aft Sample Tube Pylon Slug Pylon Base Patch APD Amplifiers 9 Electronics monitor only no control 10 Imaging Laser 11 PDS 45 laser 12 PDS 90 laser eo St Se o aa Currently there is no heater for the electronics item 9 but all the others are controlled as described in Sections 5 1 1 1 Housekeeping Window and 5 1 2 1 Advanced Control and Settings Window The physical description of the heat zones is given in the SPI Sensor Head Physical Description Section 3 1 Pictures diagrams and descriptions in that section provide an understanding of where the 12 controlled heat zones in this list exist on the sensor head Other temperatures are also monitored but not controlled such as at the CCD camera Here no associated heater is used to maintain a minimum temperature Warning Running the instrument in the pylon for extended periods at room temperature 20C or above results in excessive self heating With De ice heat off it is still possible for t
174. specific information such as the voltage pulse height that was output from each of the PDS detectors The PDS packet is shown in the timing diagram in Figure 4 2 3 The state machine waits in S3 and doesn t advance to S4 until an EXSYNC pulse is received from the frame grabber in the data acquisition system This means no more particles will be imaged until the next EXSYNC pulse is received When the EXSYNC pulse is received from the frame grabber the state machine advances from S3 to S4 In S4 the state machine outputs a CLRX signal which clears the latch that captured the last EXSYNC pulse This is done in preparation for the next particle In S4 it waits for the CLEAR HOLD signal from the DSP before advancing to S5 This signal tells the state machine that the DSP is ready for the next particle The EXSYNC pulse causes the CCD camera to download its current image to the frame grabber in the data acquisition computer EXSYNC also tells the sensor head electronics that the camera and data acquisition computer are ready to take the next picture The Basler A501 CCD camera is always taking images and downloading them to the frame grabber asynchronously to the DSP and state machine clock This occurs at the rate of 72 frames per second Each EXSYNC pulse corresponds to a single image sent SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice J2 SPEC CPI Preliminary Technical Manual
175. t notice de SPEC CPI Preliminary Technical Manual Object Structure Version 30 BlockMark Scalar Int Block mark ssseses s sSSCS Block mark sess mark ROIInfoSize Total bytes in this block variable because of the last two fields ROVer Soar im Tracks this structures version Pix Bytes Scalar Int Bytes per pixel in image if zero then image data oer Fags Sealar in Contains info about particle see Below Len Scar Float_ Computed Length of particles major axis Scalar Float Computed width of particle perpendicular to length veo Dark SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 176 SPEC CPI Preliminary Technical Manual Scalar type index meaning TBD Factor assessing confidence in particle use 0 10 Harmonics ID Array Float Cireular harmonics ofboundary var Ten Location of boundary pixels in ROI array 1D indicies var len note roi image data may follow at this point if PixBytes not equal to zero Option not currently implemented An object file consists of a file header see below and a sequence of object frames Object frames conatin a frame header and a sequence of object headers one for each ROI in the original frame Dark 2 byte word Meaning darkness number LS 5 bits Particle cutoff index 0 31 no cut off to almost fully cut off Flags 2 byte word Meaning
176. te 6 Reset the pulse shaping electronics in the PDS detectors to get ready for the next particle e State 7 Continue resetting the pulse shaping electronics in the PDS detectors If no particles are detected in the beam go to state 0 otherwise wait here The imaging laser will fire when the PIB_OK signal goes low This causes the image of the particle to be captured by the CCD camera The Camera downloads the captured image to the frame grabber which is located in the Data Acquisition System as soon as it receives the next EXSYNC pulse from the frame grabber Once the image download is complete the frame grabber interrupts the computer Before the image was downloaded the frame grabber checked the PDS STATUS signal to see if the imaging laser was fired If it was not fired then the PDS STATUS bit will be a logic low In this case the image frame Is discarded If it was fired the PDS STATUS signal will be a logic high In this case the image frame is searched for regions of interest ROIs by the Data Acquisition System These are locations in the image where particles are present The image processing algorithm subtracts the stored background image from the newly acquired frame If the subtraction results in any areas of the CCD image greater than a predefined minimum pixel size with a shadow depth greater than the user selectable particle threshold these areas are cropped from the full frame Figure 1 1 3 shows an example of an ROI that was cro
177. than this number of ROI s detected in an image then the background algorithm will not use the current frame for image mean calculation 2 is a good value to use Max ROI size in Diff image If any ROI in the image is over this number of pixels the image is rejected for background A value of 10 will work OK here Max time between images If frames get thrown out the time between the first and last accepted frame for performing ROI subtraction must be less than this number in milliseconds 700 is a good value here All these values are set in the form shown in Figure 5 3 3 SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice t17 SPEC CPI Preliminary Technical Manual 6 0 PROCEDURES 6 1 Pylon Cover Removal The CPI sensor head pylon cover must be removed to gain access to the internal sensor head This step is necessary if the internal sensor head is to be completely removed from the pylon or to perform electronics troubleshooting of the internal sensor head while in the pylon The photographs show the sensor head lying flat on a table The pylon should always be placed on a soft material such as foam to avoid scratching the outer surface This procedure can also be followed when the sensor head is mounted on an aircraft The pylon internal pressure is monitored in the Housekeeping data If the internal pressure drops during flight a leak in
178. the pylon cover s seal is indicated If the instrument was being flown in a wet environment when the pressure dropped the pylon cover should be removed after the flight The internal sensor should be inspected for moisture If moisture is found allow the pylon internal sensor to dry out before putting the pylon cover back on The AR coatings on the optical block windows are sensitive to high humidity environments Do not allow moisture to reside in the closed pylon it will damage the AR coatings Warning The CPI pylon is a high performance assembly that serves as a protective housing for the internal sensor head components and as the structural interface to the aircraft It is hermetically sealed up to approximately 65 000 ft altitude O rings and precision machined surfaces are used to achieve this seal Improper disassembly assembly of the pylon or mishandling of the components can result in damage that will compromise the pressure integrity of the pylon This may result in malfunctioning of the instrument during flight Disassembly Assembly of the pylon should only be performed by personnel who have read and become familiar with this procedure 1 Verify CPI sensor head power is turned off 2 Figure 6 1 1 shows the primary external components of the pylon assembly the pylon body pylon cover and nose cone 3 The nose cone is fastened to the pylon using 4X 6 32 socket head cap screws SHCS Figure 6 1 2 4 In order to remove the
179. tical block using a thermally conductive epoxy This interface serves as a hermetic seal between the internal pylon and air flowing through the sample tube Extreme care must be taken when working around the windows A special non metallic cleaning tool has been provided with the CPI DO NOT INSERT SHARP METALLIC OBJECTS INTO THE SAMPLE TUBE THAT CAN SCRATCH THE COATED WINDOWS ONCE THE AR COATING IS DAMAGED REPLACING THE WINDOWS IS EXTREMELY LABOR INTENSIVE AND COSTLY Cleaning of the optical windows should only be performed by personnel who have read and become familiar with this procedure using only the tools and materials described in this procedure 32 Figure 6 7 1 shows the enunciator panel and settings window indicating the PDS detector DC levels are saturated Reducing the laser power should decrease the DC levels This is satisfactory SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 145 33 34 35 36 dl 38 39 40 41 42 SPEC CPI Preliminary Technical Manual until the laser powers are reduced to below approximately 20 mW for the DC level to drop below 8 8 V The windows should be cleaned at this time Figure 6 7 2 shows the materials required to clean the windows A can of electronics grade compressed air is also necessary to blow off particulates not shown Purified reagent grade methyl alcohol should be used as a cle
180. ticle passes through the intersection of both PDS laser beams a pulse of light is observed on each of the scattered light detectors In this case both PDS detectors output voltage pulses at the same time If the pulses last longer than a minimum duration then the Particle In Beam OK PIB_OK signal goes high and a logical state machine located in the sensor head starts stepping through its 8 step cycle This state machine orchestrates the imaging of the particle the sending of data associated with that particle to the Data Acquisition Computer and the resetting of the electronics in preparation for the next particle The states of this state machine are as follows e State 0 Idle and wait for a particle If a particle is present in both beams for a set minimum duration the minimum transit time as indicated by the PIB_OK signal going high go to State 1 e State 1 Start a timer that measures the time during which the particle is in the PDS beams This is called the Transit Timer Wait for the Particle In Beam OK PIB_OK signal to go low This signal goes high when both of the PDS pulses have been high for longer than a minimum duration It goes low instantly when either one of the PDS pulses goes low At the instant when PIB_OK goes low the particle is in the object plane of the camera When PIB_OK goes low jump to state 2 e State 2 Fire the imaging laser Notify the frame grabber in the Data Acquisition System that a particle was seen
181. tificial intelligence Al code added to the real time software attempts to do the same thing using the following algorithm 1 Start with the set point stored in the CPI ini file 2 Wait X start with 5 seconds 3 Look at error between desired PDS DC level the upper limit for the DC Voltage measured found in the cpi INI file and the measured value 4 Implement proportional integral control based on error in 3 5 Record new set point 6 Goto2 Figure 5 3 2 shows the window used to change the parameters that affect this algorithm The lower two thirds of the form are for PDS laser setting control which this section discusses while the upper third is for controlling the PDS threshold to be discussed in the next section To turn off the DC level control algorithm so that the real time software lets the user maintain control leave the Algorithm Enabled checkboxes unchecked SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 111 SPEC CPI Preliminary Technical Manual POS Threshold and OC Level Control Settings POS Threshold Control Short Integration Long Integration g F Algorithm Enabled Period secl 21 Period sec 5 Increment Step s50 bas Flaches sec in 5 Min Flashes in 2 Size 4 Short Period 11 Long Period 6 Decrement fso Max Walid Total A 01 Step Size P47 for Cleandir 243 l POS DC Level Control Lazer 45 F Al
182. ts and changes to the CPI and related software at any time and without notice 164 EZ ss i 174 Oe Os Efa CFOs EIs LoG LEE LEZ Loos 184 Looe LOO a oe ae Tega 189 L90 LIT LIZ LoS 194 g Hho LOGS ies a OCs LIY AJU 20E TAIA SAUER 204 2O 206s Ziel ce LO 209 AKOS ARE BAD allies Ze tale ee Ze VOG ALs LEG PAES Zee ise Lie Vis PLP Los SPEC CPI Preliminary Technical Manual G 020 is the PDS45 DC Voltage on J1 42 Gain Offset20 0 00486000 0 000000 2 000000 8 800000 G O21 is the PDS90 Laser Power on J1 3 from photodiode monitor Gain Offset21 0 0232 0 7538 15 000000 41 000000 G O022 is the PDS90 DC Voltage on J1 23 Gain Offset22 0 00486000 0 000000 2 000000 8 800000 G 0O23 is the Imaging Laser Current Set Voltage Measured J1 47 Gain Offset23 0 0161133 27 5 20 000000 36 000000 G 0O24 is the Imaging Laser Pulse Width Voltage Measured J1 8 Gain Offset24 0 0161133 27 5 20 000000 38 000000 G OZ25 18 the 5V Supply ion Jil 4 Gain OFEsSet2Z5 07002929685 SIZ 5425 4 0 G 026 is the 5V Supply on J1 44 Gain Offset26 0 002930 0 000000 4 7500000 5 2500000 G O27 is the 12V Supply on J1 24 Gain Offset27 0 007354 0 000000 11 500000 12 500000 G 028 is the 12V Supply on J1 43 Gain Oreserve U0UN S54 30 12 122500000 9 000000 G O29 is the PDS45 Laser Power Set Point Gain Offset29 0 0102775 1 664985 12 000000 43 000000 G 0O30 is the PDS45 Threshold Set Point Gain
183. tting 14 is the PDS45 laser power set point Settingl4 4095 0 4095 l SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 162 SKa GJ TOs ides Ze ee 74 yor T6 ae Toy ec 30 ole OZ Oi 84 oo 86 ow ae 86 oo 90 vile ole Doe 94 chor 96 OH 2O Oo TOO LOT LOZ LOS ss 104 OD LOO Ms LOS LOG LLO LLE ELEZ LS 114 Elos KU JZ l and J2 19 LLT ELS LLO SPEC CPI Preliminary Technical Manual setting 15 is the PDS90 laser power set point Setting15 4095 0 4095 setting 16 is the PDS45 threshold set point Settingl6 207 100 1000 setting 17 is the PDS90O threshold set point Settingl7 207 100 1000 setting 18 is the Imaging laser current set voltage Settingle s 792 0 3920 setting 19 is the imaging laser pulse width set voltage Settingl9 3413 0 4000 setting 20 is the minimum transit time set point SettingZ0 35 L0 255 rev3l only poetuanoZi l0ss TU DO setting 22 is the APD90 amplifier temp set point Setting22 458 0 1139 Setting 23 is the camera temp set point Setting23 59 0 992 setting 24 is the PMT temp set point Setting24 237 0 970 setting 25 is the SLS laser temp set point SettingZs 125 5 0 L555 setting 26 is the SLS laser power set point Setting26 25 0 4095 setting 27 is the PMT high voltage set point Serting J Z26 O 255 setting 28 is the pylon cover patch tempera
184. tube is in the position shown in Figure 6 5 2 4 Review Figure 6 5 3 through Figure 6 5 10 before proceeding further 5 Hold the internal sensor as shown in Figure 6 5 3 and begin lowering into pylon 6 Protect the 45 PDS laser from the pylon screw boss by using the Delrin laser guard as a bumper Figure 6 5 4 SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 135 20 21 22 23 SPEC CPI Preliminary Technical Manual Pivot the internal sensor around the laser guard and lower onto the pylon spreader as shown in Figure 6 5 5 Align the inlet adapter with the internal sensor as shown in Figure 6 5 6 The internal sensor must be below the grommet surface as shown in Figure 6 5 7 Figure 6 5 8 shows the installation direction of the internal sensor into the pylon Hold the internal sensor as shown in Figure 6 5 9 and begin sliding onto inlet adapter and pylon spreader As the internal sensor slides on the inlet adapter and pylon spreader grommet the gap decreases as shown in Figure 6 5 10 When the internal sensor reaches the position approximately shown in Figure 6 5 10 the pulling fork tool is required to move the internal sensor into its final position Insert the aft sample tube into the internal sensor as shown in Figure 6 5 11 The sample tube and internal sensor may need to be lifted slightly to clear the mount base
185. ture set point Setting Z3 36 1500 1057 setting 29 is the imaging lens temperature set point Setting29 838 450 1057 setting 30 is the laser trigger timer threshold set point Setting30 0 0 4095 Gains Offsets for Readings l Gain offsetl is the Forward Sample Tube Temperature AD590 on Gain Oriseti 0 029356 1 87 7500 10 000000 352000000 G O2 is the Upper Optics Block Temp AD590 on J2 2 and J2 20 SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice E63 SPEC CPI Preliminary Technical Manual L205 Gain Offset2 0 029356 1 877500 207000000 35 000000 iba L22 G O3 is the Lower Optics Block Temp AD590 on J2 3 and J2 21 123 Gain Offset3 0 029356 1 877500 20 000000 35000000 LZA L2 Pe G O4 is the Central Sample Tube Temp AD590 on J2 4 and J2 22 L20 Gain Offset4 0 029356 1 877500 10 000000 35 000000 BAT L283 G O5 is the Aft Sample Tube Temp AD590 on J2 5 and J2 23 L29 Gain Offset5 0 029356 1 877500 10 000000 35 000000 I Og Tol G O6 is the Nose Temp AD590 on J2 6 and J2 24 T32 Gain Offset6 0 029356 1 877500 5 000000 35 000000 oe 134 G OT as the Pylon Temp AD590 on J2 7 and J2 25 SOs Gain Offset 7 0 029356 1 877500 5 000000 35 000000 T30 L37 G O8 is the old Camera Filter Drop Cop Tube AD590 J2 8 and J2 26 eto Gain Offset8 0 029356 1 877500 60 60 000000 13O AU 7G 09 is the APD45 Te
186. usting 5 2 5 Enunciator Warnings 5 3 Artificial Intelligence Al DAS Controls 5 3 1 Setting Menu Al Items 5 3 2 PDS Laser Control 5 3 3 PDS Threshold Control 5 3 4 Background Control 5 3 5 Laser Pulse Width Control SECTION GS PROCEDURES maroon ate ee ae 118 6 1 Pylon Cover Removal 6 2 CPI DSP Control Board Access When Internal Sensor Head Is Mounted in the Pylon 6 3 CPI Internal Sensor Removal 6 4 CPI Internal Sensor Running on Test Stand 6 5 6 6 6 7 6 8 CPI Internal Sensor Installation into Pylon Pylon Cover Installation Cleaning CPI Optical Windows CPI Imaging System Camera Alignment SECTION 7 APPENDICES cuiii A A 159 7 1 Mechanical Drawings for Installation on Aircraft 7 2 CPI INI 7 3 DSP Memory Address Decodes and Heater Controls 7 3 1 Reads 7 3 2 Writes 7 4 CPI ROI Data File Format SPEC CPI Preliminary Technical Manual 1 0 CPI OVERVIEW 1 1 CPI General Description The UAV CPI is an airborne atmospheric research instrument that captures high resolution images of particles as they pass through the instrument 1 1 1 Main Parts of the CPI The UAV CPI can be subdivided into three basic parts shown in the block diagram Figure 1 1 1 The first part the Data Acquisition System is housed inside a rack mount computer case This is usually mounted inside the aircraft cabin The second part is the Sensor Head which is located outside the aircraft on the fuselage or wing The third part the power system occupies sp
187. utilize the SPI serial interface protocol One is used to control the PDS45 PDS90 SLS systems will not have a PDS90 signal and imaging laser power set points the other on a system with an SLS will control the PMT high voltage set point and the SLS PDS laser power These DACS replace the need to perform writes to addresses 0x0404 through 0x0407 and 0x3001 and 0x3002 All heaters on the UAV CPI are controlled by turning on bits in the data written using the SPI1 channel with SPI1_SEL1 PF3 The SLS system PMT and laser heaters are driven by TMRO and TMR1 outputs respectively These outputs feed into the DSP_HSKP CPLD and require that GP 8 be written with a value of one to enable the heater see WRITES item 4 above The relays and FETs that control power are on the relay and sensor board that piggybacks the main DSP control board see Figure 3 SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice INE AN SPEC CPI Preliminary Technical Manual Table 7 3 2 Heater Control Bits and Applied Power Location Supply Power Relay FET Voltage Watts FWD Sample 115 AC 159 TubeXOTE Bit Optics Block 115 AC UpperXo Optics Block 115 AC LowerNOTE Sample Tube DEG se pe Tube 5 ImagingLens ISAC KR 6 PDS45APD U5AC 66 KO PDS90 APD ISAC 66 KIO Pylon Cover 115 AC 330 K12 Patch 9 PylonShig ISAC 330 K3 O een a a a P
188. ve The control algorithm will do nothing until the target DC value differs from the actual DC value by more than this value SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 112 SPEC CPI Preliminary Technical Manual Err Thresh Stop Change Volts away from the target to stop the algorithm Once the difference between the desired DC value and the actual DC value is less than this value the control algorithm will end This value should be smaller than the Err Thresh Start Change value just discussed Stable State Max Range For min stability time period which will be the next field that we discuss all the values need to be within the Stable State Max Range Volts to be considered good If the Voltage samples of the laser DC level within a window of time equal to Min Stability Time Period vary by more than this setting the control will not be implemented This feature keeps the algorithm from becoming unstable if the measurements are varying too erratically Min Stability Time Period How long the PDS DC levels must be within Stable State Max Range Volts of each other before the proportional integral PI control will begin See Stable State Max Range parameter explanation Averaging time period How long to average PDS DC levels for comparison with set point This is time T in the difference equation discussed below Adaptation Parameter Ki T F
189. ware at any time and without notice 156 SPEC CPI Preliminary Technical Manual iv 10 Pa en Samo Cee Pe PROBE Vie r Oa lt gt Ea CENTER OF PIN IS IN FOCUS AND HORIZONTALLY AND VERTICALLY CENTERED ON ARRAY Ready PROSE GETTING RAO WM Man DE BA ooreo Hodo ra DRD sir Figure 6 8 10 SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice Rey SPEC CPI Preliminary Technical Manual Duta Mier OUZ TOO POCONO OISARLID Tene hee hes i xj F was eirg rarah Wei tat STO T Video re K Deice ON r tow PROBE ON sre BKGAOUND Statutes x froma Poste EONA das Spaad brv sec 140 r a feces Z 1am o a o 15333 39535 o wre Verte Aierepied 6 FSS PERG24 48048 PST PIETOSO CPSs POR roLS3 C9509 THE O49 S0O 44045 J k PSS SO0_98 1349753 Ven dbaaan Teme 22028288 PALA ase Tier Aze ma m hasarti Len hiuat4ar tien zhat ARR 3 e eo TO 451 406 95095 Tie 49 520 440441 Fie 199 626 90080 124 665 402 300008 Tite 455 200 950009 PPS 405 174 190080 xj N 34 341 or TER LRL LAEE LT 24 82 Tee Dar pe oN 134 983 ter zzrzarne fe Probe Dispi Piore Lovers aig Thesa E Poss fo E _ aa 3 g Aan Baachgound Opon TREE Fipan Aane Iecr E0 Eiobes Threshoad fic parens p9 Pah A Sa td Pe See 39499 Fot 43 626 29099 Pea 599 666 44099 163 353 4 135104 x Tor 405 690 940
190. x 100 respectively Imaged particles are the number of ROIs found during the interval Particle Conc is the derived particle concentration and ROI Conc is the derived number of ROIs in the last interval period given in units of number per liter PDS strobes is the number of times the PDS system has seen a qualified particle pass through the sample volume during the interval and Average Dead Time is the time in seconds summed over the interval that the sensor head was busy processing a current particle and thus unable to image subsequent particles SPEC Inc reserves the right to make improvements and changes to the CPI and related software at any time and without notice 12 SPEC CPI Preliminary Technical Manual 9 1 2 Settings Menu The settings menu is shown in Figure 5 1 5 below The Probe and Display selection brings up the window labeled Settings in Figure 5 1 1 The Settings window provides easy access to many parameters that are also found but with more searching required in the housekeeping and advanced control and settings windows discussed elsewhere File View Settings Commands Window Help STOP Probe and Display PROBE dvanced Control and Settings BECP 40 Background Settings 40 POS Control Settings SPRLU Settings Single Board Computer Settings Figure 5 1 5 The Settings Menu The Al Background Settings and Al PDS Control Settings are discussed in Se
191. yed and reported Once the image mean is at a desirable value e g somewhere between 100 and 150 though this is different for each probe turn off live video by unchecking the Live Video box A new background should be taken immediately after any changes are made to the imaging laser set points If not the background subtraction will now have a large offset due to the changed image mean causing the particle processing algorithm to work poorly or not at all Data File D 02180840 r0i RECORDING DISABLED Time 2 18 9 25 37 1a A 18 x File View Settings Commands Window Help Live STOP Record TA Freeze Belg Video TT Data eG Dele ONT Display SETUNGS Statistics Frame Particle amp see nace cli sec ims Captured 70 0 g Valid Frms i 100 0 Last Frame mg Mean 137 kg Mean 136 Backgrounds a3 Probe Disp Hist Plots Lasers PDS 45 etectorDC Level 4 aed y aser Laser Power Setpoint Laser Power Setpoint 4095 PDS 90 Detector DC Level 6 6971 V Laser Power Actual 39 707 mw Laser Power Setpoint 40 338 mw 4095 IMAGING kg Mean Laser Curent Actual oe ulse Width Actual 32 0117 V aser Current Setpoint 32 4023 3792 E Pulse Width Setpoint fai 9218 Z 3 APPLY RESET E Ready PROBE GETTING BACKGROUND um start 4 ESI EAvata Fite D 0218084 DAD ozsam Figure 5 1 13 Main GUI window and Rates and Image parameters window in Live Video mode 5 1 5 Probe Sen

Download Pdf Manuals

Related Search

Related Contents

Handbuch - im BUSINESS IT AG Online-Shop  Manual - Tramsoft  取扱説明書 - M  警告 注意 - Drum-tec  Instructions for Use-English  Butler(5.1) Manual  BEDIENUNGSANLEITUNG 2013 1190 Adventure EU 1190  Sony DCR-PC109 Notes  

Copyright © All rights reserved. Failed to retrieve file