User Manual Quanser Qball-X4
Contents
1. Compatibilit 4 Interface External mode nt Yerhication 4 HosteT arget interface Hodele O Transport layer MES fle name quanc_ comm Real Time Workshop ME file arguments w d tmp uri u tepip IP of Gumstis 17001 H Comments Memory management C Static memor allocation Figure 19 Configuring MEX file arguments 5 Select External for simulation mode instead of Normal which indicates that the model is to be run on the target machine Gumstix rather than simulating the model on the host machine 6 The model is now ready to be compiled on the target vehicle If the wireless connection to the vehicle has been established a QuaRC console can be opened to show additional messages and progress during model compilation by going to the menu item QuaRC Console for all Building the model QuaRC Build will begin the code genera tion and compiling steps Output from the compilation is shown in the QuaRC console This step may take a few minutes to complete Document Number 829 Revision 12 Page 19 Quanser Qball X4 User Manual 6 4 Qball X4 Sensors This section describes the blocks that are used to read the Qball X4 sensors in Simulink and write outputs to the motors The QuaRC Hardware In the Loop HIL blockset it used to communicate with Quanser data acquisition cards including the HiQ For detailed informa tion on the HIL blockset see the QuaRC HIL user guide in the MATLAB help2. Follow the directions of the charging system that is supplied to ensure the batteries are charged properly and safely 7 Troubleshooting Guide For any issue the first and easiest troubleshooting solution on any electronic device is to re boot the device Turn off the Qball X4 then turn it back on again For troubleshooting any Document Number 829 Revision 12 Page 23 Quanser Qball X4 User Manual problem with the Qball X4 it is always a good idea to open the QuaRC console in case ad ditional information is printed to the console by going to the QuaRC menu and clicking on Console for all The console must be opened after the Qball X4 has booted and estab lished a wifi connection If the console is opened successfully it establishes a connection to the target and the console window has the title QuaRC Console for at tepip 182 168 1 xxx 17000 where xxx corresponds to the IP address of the Qball X4 7 1 The model fails to build connect or the QuaRC console does not successfully open 1 Remove the Qball X4 cover so that the HiQ is visible Plug in the battery to the battery connector Figure 8 Turn on the power switch and look at the bottom of the Gumstix attached to the bottom of the HiQ for the orange power LED After approximately 30 seconds a blue LED will flash to indicate the wifi module is powering on and 1s at tempting to connect to another computer on the ad hoc wifi network If the blue LED fl
3. angles Assuming that the yaw angle is zero the dynamics of motion in X and Y axes can be written as M X 4 Fsin p MY 4Fsin r Assuming the roll and pitch angles are close to zero the following linear state space equa tions can be derived for X and Y positions 7 01 0 0 X 4K Xj 0 KI ge EN lip 9 0 w ofS 10 0 0 101 0 0 Y _4K Y 0 yJ_jo 0 Ser oly jol 0 0 w off e 10 0 0 5 4 5 Yaw Model The torque generated by each motor t is assumed to have the following relationship with respect to the PWM input u T Kyu where A is a positive gain and its value is given in Table 3 The motion in the yaw axis is caused by the difference between the torques exerted by the two clockwise and the two counter clockwise rotating propellers The model of the yaw axis is shown in Figure 14 The motion in the yaw axis can be modeled using the following equation J O AT In this equation is the yaw angle and J is the rotational inertia about the z axis which is given in Table 3 The resultant torque of the motors At can be calculated from Document Number 829 Revision 12 Page 13 Quanser Qball X4 User Manual NTS T tH Tae t The yaw axis dynamics can be rewritten in the state space form as 0 Cata AP yale AT a 0 Olle y y Js Ha E EST Figure 14 A model of the yaw axis with propeller direction of rotation shown Document Number 829 Revision 12 Page 14 Quanser Qball
4. under QuaRC Targets User s Guide Accessing Hardware Table 4 lists the HIL blocks used to communic ate with the Qball X4 s data acquisition hardware The HIL Initialize block selects the DAQ board and configures the board para meters The HIL Initialize block is named via the Board name parameter and all other HIL blocks reference the corresponding HIL Initialize through its name For the HiQ there is a board specific option for selecting the gyroscope model aa eens installed on the HiQ The gyro model is specified by typing Qball 4 HiG fhiq_aero t gyro model 16405 in the HIL Initialize Board specific options parameter or by selecting the model from the board specific options dialog The valid values for the gyro model option are 16350 16360 16400 and 16405 The gyroscope number is found on the label of the gyroscope 4 in Figure 5 The HIL Read Write block is used to read sensor measurements from the HiQ and write motor commands to the four Qball X4 motors The inputs and outputs are specified with numeric channel numbers given in Table 5 and Table 6 re spectively HIL Read Write Oball 4 Hil Table 4 HIL blocks used by the Qball X4 To initialize the HiQ board a HIL Initialize block must be placed in the model The HIL Initialize block is used to initialize a data acquisition card and setup the I O parameters In the HIL Initialize block select the board type hiq aero to configure the
5. 9 Revision 12 Page 2 Quanser Qball X4 User Manual Runs model controller Wifi Send code to target Gumstix Send Receive scope data update runtime parameters HIQ and Gumstix Figure 2 Communication Hierarchy 3 Prerequisites To successfully operate the Qball X4 the prerequisites are 1 To be familiar with the wiring and components of the Qball X4 11 To have QuaRC version 2 0 installed and properly licensed 111 To be familiar with using QuaRC to control and monitor the vehicle in real time and in designing a controller through Simulink See Reference 2 for more details Document Number 829 Revision 12 Page 3 Quanser Qball X4 User Manual 4 References 1 Gumstix http gumstix com 2 QuaRC User Manual type doc quarc in Matlab to access 3 Park 400 Brushless motor 740Kv http hobbyhobby com store product 68199 Park 400 Brushless Outrunner Motor 740K v 4 Propellers description and technical information http www rctoys com re products APC 10 047 SF CR html 5 System Hardware and Software Description 5 1 Main Components To setup this experiment the following hardware and software are required e Qball X4 Qball X4 as shown in Figure 1 above e HiQ QuaRC aerial vehicle data acquisition card DAQ e Gumstix The QuaRC target computer An embedded Linux based system with QuaRC runtime software installed 1 e Batteries Two 3 cell 2500 mAh Lithium Polymer
6. HiQ DAQ and if desired enter a name in the Board name field as shown in Figure 20 Next to read and write from the HiQ add a HIL Read Write block to the model note that the HiQ is optimized for best performance when a single HIL Read Write block is used in a model adding more HIL I O blocks may reduce the performance particularly the maximum sample rate In the HIL Read Write block select the board name corresponding to the board name given in the HIL Initialize block The channels available for reading and writ ing for the HiQ are listed in Table 5 and Table 6 below Enter the channel numbers to be read written or use the browse buttons to open a channel selection dialog as shown in Fig ure 21 Document Number 829 Revision 12 Page 20 Quanser Qball X4 User Manual Source Block Parameters HIL Initialize HIL Initialize Initializes a hardyvare in the loop card Navigation Goto HIL blocks using this board Main Board name Clocks Qball X4 HIQ Lee ae ey Analog Inputs Board type eee hic aero Analog Outputs eee Board identifier Digital Inputs Digital Outputs Board specific options a Encoder Inputs gyro_model 16405 PAM Outputs C Active during normal simulation Other Outputs Figure 20 HIL Initialize block with the HiQ board selected Channel type Read channel Description numbers amaos O e O O encoder mei Table 5 HiQ input channels Document Number 829 R
7. Specialty Plants User Manual QUAN SER UNN G VATE Su ok Te Quanser Qball X4 Quanser Qball X4 User Manual Table of Contents le TAMER O CUI CLL OM osessi cca Suctonsec cs T usteadic yore aula setisite wS vse N O E O l 2 Operator Warina Sonses AE O e l JSPT S ES ar A E E EON 3 kR TEE e E A E ONEEN 4 5 System Hardware and Software DeSCTription ccccccccceeecccceceeeeeeeceaeasesssesseeeeeeeeaeaeees 4 Dees Wai OMI OMe S eE A N A eases 4 T DO A OMAN saath oes cep el A tet eacas 4 5 94 Dalle XA COMPONENTS oirr re T etnies E 5 OLODABA A I n A OAS 8 De ODAO se rrsiaah asta a yaad Seatac A a E T ale ead ena 9 Io ODA F POW CE aeae E N N eeaateliins acc da nsonssen cooks 10 5 3 4 Qball X4 Motors and Propellers se 1 4 iiiiatesensisidhiwonac eu Asieidietat as odeinoinacaanctees 10 De ODALA Moderneissa eile hactssiast ce a sideteabinia tiaiihec a E 10 SAd ACUO A S reires care secs spacsnecceteandhanedocskatestexteeciseaaeeeacabetedaeseereeseee eee akon 10 SA2 ROP ite by MOQO rciris reiia eE a e niaceangsusnd eae aceasta ews 11 yee REE BRIN Ode berr e E E E 12 IAA AY POSON ModE I cet sts cctr ste har tet A T Se gaa aaa iam icba bo 13 eV AV MOI Loain E as ert va cence E ae oad eed oc de waa 13 OSV SUSIE AS CUD iccasutacnrcora tortie comemenenede o e sbegsamlees veatianeite E r EAS 15 6 1 Establishine Wireless Connecti Onenen nd an easier nin wes 15 6 2 Oba A 4 VENICE SEU Daea ts eed teaterndthnaeate E ee Mogae 17 6 5 Qua
8. X4 User Manual Parameter Value K 120 N w 15 rad sec Ti 0 03 kg m J itch 0 03 kg m M 1 4 kg K 4 N m E 0 03 kg m L 0 2 m Table 3 System parameters 6 System Setup Section 6 1 walks through setting up a wireless connection with Windows Section 6 2 de scribes setting up the vehicle hardware Section 6 3 explains how to properly setup the QuaRC Simulink interface and create a new Simulink model that will run on the vehicle Finally Section 6 4 describes the blockset and tools used to read the vehicle sensors and write motor outputs 6 1 Establishing Wireless Connection The Qball X4 uses an ad hoc peer to peer wireless TCP IP connection for communicating with the host computer and or other Quanser unmanned vehicles The Qball X4 package comes with a USB wireless adapter to setup the host computer with a wireless connection for use with the Qball X4 and other Quanser unmanned vehicles These steps outlined be low for setting up the host computer wireless connection only need to be performed once 1 After installing the USB wireless adapter that is provided Windows should detect a net work called GSAH an Unsecured Computer to Computer Network This is the peer to peer network used by the vehicle 2 Open the Status of the wireless network then click on Properties 3 Under This connection uses the following items scroll down to Internet Protocol TCP IP then double cli
9. ashes and remains on then the wifi module is functioning and is able to find another node on the ad hoc wireless network If the blue LED flashes and then turn off the Gumstix is not able to detect other nodes e g the host PC on the ad hoc wireless net work Check that the USB wifi adapter is inserted properly in the host PC and is con figured according to the network configuration procedure outlined in this manual Sec tion 6 1 Establishing Wireless Connection Verify that the host PC is connected to the wireless ad hoc GSAH network and try to successfully ping the Gumstix by going to the Windows Start Run and typing ping 182 168 1 xxx without quotation marks where xxx corresponds to the IP address of your vehicle If the blue LED never flashes the wireless antenna or wireless module may be disconnected Turn off the power and verify that the Gumstix wireless module and antenna are properly connected The wire less module shown in Figure 23 is located on the bottom side of the green Gumstix com puter Make sure the wireless module and antenna are secured and retry the above steps to establish a wireless connection Document Number 829 Revision 12 Page 24 Quanser Qball X4 User Manual Ea wifi module EU bottom Figure 23 Wifi Module 7 2 The Qball X4 sensors are not being read correctly or they are stuck at some constant value 1 Using the HIL Read block output all possible channels Check these outpu
10. ations The protective cage is a crucial feature since this unmanned vehicle was designed for use in an indoor laboratory where there are typically many close range hazards including other vehicles The cage gives the Qball X4 a decisive advantage over other vehicles that would suffer significant damage if contact occurs between the vehicle and an obstacle To measure on board sensors and drive the motors the Qball X4 utilizes Quanser s on board avionics data acquisition card DAQ the HiQ and the embedded Gumstix computer The HiQ DAQ is a high resolution inertial measurement unit IMU and avionics input output I O card designed to accommodate a wide variety of research applications QuaRC Quanser s real time control software allows researchers and developers to rapidly develop and test controllers on actual hardware through a MATLAB Simulink interface QuaRC s open architecture hardware and extensive Simulink blockset provides users with powerful controls development tools QuaRC can target the Gumstix embedded computer automatically generating code and executing controllers on board the vehicle During flights while the controller is executing on the Gumstix users can tune parameters in real time and observe sensor measurements from a host ground station computer PC or laptop The interface to the Qball X4 is MATLAB Simulink with QuaRC The controllers are developed in Simulink with QuaRC on the host computer and these models are do
11. axis and the actuator dynamics for each propeller the following state space equations can be derived 0 1 0 0 ol 0 Al lor E jaj oar yV E ele w To facilitate the use of an integrator in the feedback structure a fourth state can be added to the state vector which is defined as follows s 0 After augmenting this state into the state vector the system dynamics can be rewritten as 5 9 1 9 Ola fo allo o 2 olfal fo J JAF 9 0 of o 10 0 0 0 4 3 Height Model The motion of the Qball X4 in the vertical direction along the Z axis is affected by all the four propellers The dynamic model of the Qball X4 height can be written as M Z 4F cos r cos p M g where F is the thrust generated by each propeller M is the total mass of the device Z is the height and r and p represent the roll and pitch angles respectively The total mass M is given in the Table 3 As expressed in this equation if the roll and pitch angles are nonzero the overall thrust vector will not be perpendicular to the ground Assuming that these angles are close to zero the dynamics equations can be linearized to the following state space form afe 9 2 fo fo Z _ 0 0 o i 0 a M jut 10 0 o Olt fo 0 1 0 0 O Document Number 829 Revision 12 Page 12 Quanser Qball X4 User Manual 5 4 4 X Y Position Model The motion of the Qball X4 along the X and Y axes is caused by the total thrust and by changing roll pitch
12. batteries e Real Time Control Software The QuaRC Simulink configuration as detailed in Reference 2 9 2 X4 Diagram Figure 3 below is a basic diagram of the Qball X4 showing the axes and angles Note that the axes follow a right hand rule with the X axis aligned with the front of the vehicle JT tail or back of the vehicle is marked with colored tape When flying the vehicle it is common to orient the vehicle such that the tail is pointing towards the operator with the positive X axis pointing away from the operator Document Number 829 Revision 12 Page 4 Quanser Qball X4 User Manual Figure 3 Qball X4 axes and sign convention 5 3 Qhall X4 Components The components comprising the Qball X4 are labeled in Figures 4 to 11 and described in Table 1 Document Number 829 Revision 12 Page 5 Quanser Qball X4 User Manual Figure 4 Qball X4 cage and frame gt ANALOG 6350AMLZ ADIS1 Figure 6 HiQ cover Figure 5 HiQ DAQ Document Number 829 Revision 12 Page 6 Quanser Qball X4 User Manual i HEN m JESI R Figure 9 ESCs and batteries D d Figure 10 Optional sonar and sonar mount Figure 11 Motor and propeller Document Number 829 Revision 12 Page 7 Quanser Qball X4 User Manual ID Description ID Description Qball X4 protective cage GPS serial input Qball X4 frame Battery switch 4 HiQ inertial measurement unit Speed controllers ESCs HiQ ser
13. ck on it 4 Instead of obtaining an IP address of the computer automatically enter the following IP address 182 168 1 xxx any unused number Document Number 829 Revision 12 Page 15 Quanser Qball X4 User Manual Subnet mask 255 255 255 0 Default gateway 182 168 1 xxx same as IP Internet Protocol TCPAIP Properties General fou can get IFP settings assigned automatically if your network supports this capability Othenwse you need to ask your network administrator for the appropriate IP settings Obtain an IF address automatically Use the following IP address IP address 182 768 1 118 Subnet mask 255 255 255 0 Default gateway 182 768 1 118 Obtain ONS server address automatically Use the following DNS server addresses Preferred ONS server Poe athe Alternate DNS server Lee Figure 15 Wireless USB adapter settings 5 Connect to the GSAH network through the Windows network connections list 6 If the Qball X4 is powered on the Qball X4 can be pinged by typing ping IP of Qball X4 in the Run box in Windows go to the Start menu and click Run Type the name of 4 program folder document or Internet resource and Windows will open it For you Open ping 162 166 1 200 ww Figure 16 Pinging the Qball xX4 Document Number 829 Revision 12 Page 16 Quanser Qball X4 User Manual 6 2 Qball X4 Vehicle Setup 1 First check that all m
14. d inside a function call subsystem and con nected to the Computation Time block to determine their execution time during each sample Document Number 829 Revision 12 Page 25 Quanser Qball X4 User Manual instant This helps identify the bottlenecks in the model blocks subsystems with the highest execution time and can identify blocks subsystems whose computation time is greater than the sample time of the model Try increasing the sample time of those blocks whose compu tation time is greater than the sample time of the model so that the blocks run in a slower rate thread 7 4 Trying to start the Qball X4 model results in the error Unable to locate the dynamic link library or shared object 1 This error indicates that the Qball X4 driver is not found on the target Make sure that the model target type is set to Linux ARM by navigating to the QuaRC menu QuaRC Op tions Real Time Workshop pane and changing the System target file to quarc _ linux arm tlc Open a console through the QuaRC menu QuaRC Console for all and verify that the con sole window displays the target IP of your vehicle in the window title 7 5 Building a model fails with the error Not enough system resources are available to perform the operation The hard disk is full on the Gumstix computer 1 When several models are compiled the disk space on the Gumstix may become full and you will no longer have space to build models Using the clean option
15. evision 12 Page 21 Quanser Qball X4 User Manual Description Write channel numbers amaos O me O Channel type Table 6 HiQ output channels Select channels Seles Description Select the desired channels from the list of available channels and click the Add button to add them to the list of channels selected Use the Remove lt button to remove channels from the list Reorder the selected channels using the Move Up and Move Down buttons Channel selection Channels available Channels selected Altitude Gyro X axis radis Pressure sensor airspeed Pa Pressure sensor altitude Pa Temperature axis Celcius Temperature Y axis Celcius Temperature lt axis Celcius Select All Clear All Move Up conflict Mone Figure 21 Channel selection dialog for the HiQ Gyro Y axis tadis Gyro 2 axis tadis Acceleration X axis mvfs 2 Acceleration Y axis mia 2 Acceleration axis mfs 2 Magnetometer x axis Gauss Magnetometer Y axis Gauss Magnetometer 2 axis Gauss Operating capacity 3 For the Qball X4 PWM outputs 0 3 are used to command the four motors The range of PWM output values is 0 05 to 0 10 5 to 10 of a 20ms duty cycle which corresponds to a Ims to 2ms pulse respectively A command of 0 05 corresponds to zero throttle which will cause the motors to stop A command of 0 10 corresponds to full throttle Document Number 829 Revision 12 Page 22 Quan
16. in the QuaRC menu under QuaRC Clean all will remove all generated code and compiled code for the current model but this will only free up the space used by the current model Clearing all models from the Gumstix hard disk must be done manually using PuTTY or any ssh client Using PuTTY log into the Gumstix by connecting to it using the IP listed on the vehicle and use the user name root and password quanser without quotation marks Navigate to the var spool quarc directory which is where all generated code and compiled models reside Use the ls command to list all contents of this directory to see all models that have been downloaded to the Gumstix Note be careful executing any remove delete command on your Gumstix as incorrect usage could perman ently damage the file system rendering the Gumstix unusable Individual models code can be manually removed from the var spool quarc directory To remove all generated code and controllers run the command rm rf var spool quarc without quotation marks To confirm there are no longer any models on the Gumstix execute the command ls var spool quarc and there should be nothing listed Document Number 829 Revision 12 Page 26
17. kG Ouanser Red lme COnTOl enna a N a a eaaetinaeeaeetisate 18 OA ODA XA SOS aa a a aa a aa 20 Te FEOUDICS ho otoa CHUNG C aa a adarsedanaeetn eae 23 7 1 The model fails to build connect or the QuaRC console does not successfully open 24 7 2 The Qball X4 sensors are not being read correctly or they are stuck at some constant 7 3 The Simulink model appears to run slowly 1 e the simulation time runs slower than actual time or the console displays the message Sampling rate is too fast for base TVG E E N T EE EEEO NE assented cacti EA PEE onesies N A T ET ei A 25 7 4 Trying to start the Qball X4 model results in the error Unable to locate the dynamic Mnk bray Or siared ODI SCL asriar e a e E AN Osun ORRE 26 7 5 Building a model fails with the error Not enough system resources are available to perform the operation The hard disk is full on the Gumstix computet 008 26 Document Number 829 Revision 12 Page i Quanser Qball X4 User Manual 1 Introduction The Quanser Qball X4 Figure 1 is an innovative rotary wing vehicle platform suitable for a wide variety of UAV research applications The Qball X4 is a quadrotor helicopter design propelled by four motors fitted with 10 inch propellers The entire quadrotor is enclosed within a protective carbon fiber cage Patent Pending The Qball X4 s proprietary design ensures safe operation as well as opens the possibilities for a variety of novel applic
18. ler is modeled using the following first order system Document Number 829 Revision 12 Page 10 Quanser Qball X4 User Manual F K 4x 1 S W where u is the PWM input to the actuator w 1s the actuator bandwidth and K is a positive gain These parameters were calculated and verified through experimental studies and are stated in Table 3 A state variable v will be used to represent the actuator dynamics which is defined as follows PEE 2 5 4 2 Roll Pitch Model Assuming that rotations about the x and y axes are decoupled the motion in roll pitch axis can be modeled as shown in Figure 13 As illustrated in this figure two propellers contrib ute to the motion in each axis The thrust generated by each motor can be calculated from Eq 1 and using its corresponding input The rotation around the center of gravity is pro duced by the difference in the generated thrusts The roll pitch angle can be formu lated using the following dynamics JO AFL 3 where J J roll J sey 4 are the rotational inertia of the device in roll and pitch axes and are given in Table 3 L is the distance between the propeller and the center of gravity and AF F F 5 represents the difference between the forces generated by the motors lia Figure 13 A model of the roll pitch axis Document Number 829 Revision 12 Page 11 Quanser Qball X4 User Manual By combining the dynamics of motion for the roll pitch
19. nging batteries A LiPo batteries can be dangerous if charged improperly Review the battery charging procedures and monitor battery levels frequently during flight The 3 cell LiPo batteries can become damaged and unusable if discharged below 10 V It is recommended that the batteries be fully charged once they reach 10 6 V or less 5 3 4 Qball X4 Motors and Propellers The Qball X4 uses four E Flite Park 400 740 Kv motors 3 17 in Figure 11 fitted with paired counter rotating APC 10x4 7 propellers 4 16 in Figure 11 The motors are moun ted to the Qball X4 frame along the X and Y axes and connected to the four speed control lers which are also mounted on the frame The motors and propellers are configured so that the front and back motors spin clockwise and the left and right motors spin counter clock wise 5 4 Qball X4 Model This section describes the dynamic model of the Qball X4 The nonlinear models are de scribed as well as linearized models for use in controller development For the following discussion the axes of the Qball X4 vehicle are denoted x y z and are defined with re spect to the vehicle as shown in Figure 3 Roll pitch and yaw are defined as the angles of rotation about the x y and z axis respectively The global workspace axes are denoted X Y Z and are defined with the same orientation as the Qball X4 sitting upright on the ground 5 4 1 Actuator Dynamics The thrust generated by each propel
20. otors are securely fastened to the vehicle frame Check that the propellers are firmly attached to the motors in the correct order clockwise propellers viewed from the top on the front and back motors counter clockwise propellers on the left and right motors Note that the back motor is indicated by a bright colored marking on the Qball X4 frame Check that the motors are firmly secured to the frame regularly after every 2 hours of flight Over time vibrations in the frame may loosen the motor mounts If a motor or mount feels loose tighten it immediately If a propeller is loose use an allen key to remove the cap holding the propeller to the motor and ensure the propeller mounting shaft is pushed fully down onto the motor shaft Replace the propeller on the mounting shaft and replace the motor cap and tighten it with an allen key Never change propellers or other components of the Qball X4 with batteries connected 2 Install the batteries Placing the Qball X4 upsidedown so that it rests on the top of the cage Align the two Qball X4 batteries with the plate located on the bottom of the frame and secure the batteries tightly using the two velcro straps as shown in Figure 17 Connect the batteries to the battery connectors and place the Qball X4 upright again so it rests on the bottom of the cage Velcro strap Figure 17 Batteries secured with velcro straps 3 Power on the Qball X4 using the two power switches connected to
21. ser Qball X4 User Manual The 3 axis gyroscope and accelerometer measurements are used to measure the Qball X4 dynamics and orientation roll pitch and yaw The magnetometer can be used as a digital compass to measure the Qball X4 heading yaw angle These IMU inputs are crucial for controlling the flight of the Qball X4 The operating capacity input measures the battery capacity as a percentage 0 1 of the Qball X4 s input voltage operating range from 10V minimum to 20V maximum Since the LiPo batteries used to power the Qball X4 should be charged at 10 6V the operating capacity should be monitored note that 10 6V corresponds to an operating capacity of 0 06 or 6 Figure 22 shows an example of how the operating capacity can be monitored so that a low battery warning will be displayed on the host PC 1f the operating capacity reaches 8 or less corresponding to 10 8V or less using the Show Message on Host block found in the Simulink library under QuaRC Targets Sinks Error Handling Note that the HiQ input voltage measurement can be calculated according to the formula V 10x 10 where x is the operating capacity Show Message on Host operating capacity Compare To Constant Show Message on Host Dow battery Constant Figure 22 Monitoring the HiQ battery level Note that the HiQ operating capacity measures only the battery used to power the HiQ It is recommended that the Qball X4 batteries are always changed in pairs
22. the battery cables Document Number 829 Revision 12 Page 17 Quanser Qball X4 User Manual 11 in Figure 8 After 1 minute the Gumstix wireless module should be active Connect to the GSAH ad hoc network on the host PC see section 6 1 Establishing Wireless Connection 6 3 QuaRC Quanser Real Time Control Simulink should have a new menu item called QuaRC once QuaRC has been installed The following steps are required to setup a new QuaRC model for the Qball X4 1 Create a new Simulink model or open an existing model to be run on the Gumstix 2 Click on the QuaRC menu then select Options 3 The System target file under Real Time Workshop should be quarc linux arm tlc Browse through the system target list to locate the proper file if necessary Figure 18 u Configuration Parameters untitled Configuration Active Select Target selection bo Sol mes System target file quarc_linus_arm tle i Data Import Export Optimization Language Diagnostics Description QuaR C Linus 4AM Target Sample Time l Data Validity H Type Conversion H Connectivity Compatibility Model Referencing i Saving Hardware Implementation i Model Referencing Documentation and traceability Description tlc Feal Time Workshop Embedde a tlc Real Time Workshop Embedde tlc Visual C C Project Makel tlc Generic Real Time Target Real Time workshop tle Visual C C Project Makel _m alloc
23. tlc Generic Real Time Target 1 grt_malloc tle Visual C C Project Makej quarc_intime tle puak IHNtime Target guak Linux ARM Target 7 Comments Symbols Custom Code i Full name C Program Files Quangers QuaRC quarcquarc_linue_ arm the Template make file quarc_default_trnt Make command make rt Figure 18 QuaRC Option Menu 4 In order to run the QuaRC model on the target vehicle the target s IP address must be specified To setup the default target address for all linux ARM targets go to the Document Number 829 Revision 12 Page 18 Quanser Qball X4 User Manual QuaRC menu and select Preferences The Target type parameter should be set to linux arm Replace the Default Model URI with the IP address of the desired target vehicle e g tcepip 182 168 1 200 17001 without quotes Alternatively to set the target address for the current model only open the model options under the QuaRC Options menu and choose Interface on the left hand pane Under the MEX file arguments type w d tmp uri u tcpip IP of Gumstix 17001 Include the single quotation marks Figure 19 Replace IP of Gumstix with the IP of your Gumstix e g tcepip 182 168 1 200 17001 u Configuration Parameters untitled Configuration Active Select Software environment Target function library cage ANSI H Data Import E sport y l i Diagnostics be Gample Time Type Conversion Connectivity Data exchange
24. ts using scopes and displays and determine if the problem lies with a particular sensor or set of sensors or if the issue is global across all sensors 7 3 The Simulink model appears to run slowly i e the simulation time runs slower than actual time or the console displays the message Sampling rate is too fast for base rate 1 The maximum sample rate recommended for the Gumstix is 500 Hz 0 002 s However if there are complex calculations such as image processing performed within the model then this could potentially limit the sample rate of the model Try reducing the model sample rate in the menu QuaRC Options Solver by increasing the Fixed step size funda mental sample time parameter or change sample rates of blocks that take longer to run 2 The HIL Read Write block should only be used once in a diagram These blocks perform large data transfers between the HiQ and the controllers so placing more than one of these blocks will cause multiple reads to be performed in the same sample instant which is unne cessary To achieve the optimal performance use only one HIL Read Write block for the en tire model 3 To determine the execution time of blocks or subsystems within the model use the Com putation Time block found in the library under QuaRC Targets Sources Time This block outputs the computation time of a function call subsystem measured using an independent high resolution time source Blocks can be place
25. vo PWM outputs LiPo batteries 7 HiQ daughterboard with optional 16 Propeller 10x4 7 receiver Ce Reewerms T17 Mon 9 sms SidY Sd Table 1 Qball X4 components 5 3 1 Qball X4 frame The Qball X4 frame 2 in Figure 4 is the crossbeam structure to which the Qball X4 com ponents are mounted including the HiQ DAQ motors and speed controllers The frame rests inside the Qball X4 protective cage 1 in Figure 4 The Qball X4 s protective cage 1s a carbon fiber structure designed to protect the frame motors propellers and embedded control module HiQ and Gumstix during minor collisions The cage is not intended to withstand large impacts or drops from heights greater than 2 meters A Do not pick up the Qball X4 from the cage as this may stress the cage and cause damage Instead when transporting the Qball X4 lift it from the ends of the frame as in Figure 12 using both hands to lift the frame from both sides Document Number 829 Revision 12 Page 8 Quanser Qball X4 User Manual Figure 12 Pick up the Qball X4 from both ends of the frame 5 3 2 HIQ DAQ The HiQ DAQ is the Qball X4 s data acquisition board Together with the Gumstix embedded computer the HiQ controls the vehicle by reading on board sensors and outputting motor commands Each motor speed controller 13 in Figure 9 is connected to a PWM servo output on the HiQ 5 in Figure 5 There are 10 PWM servo output channels available on the HiQ and the
26. wnloaded and compiled into executables on the target Gumstix 2 seamlessly A diagram of this configuration 1s shown in Figure 2 Section 2 outlines operator warnings found throughout this manual Section 3 goes through the prerequisites and Section 4 lists various documents that are referenced in this manual The general system description component nomenclature specifications and model parameters are all given in Section 5 Section 6 goes into detail on how to setup the Qball X4 Lastly Section 7 contains a troubleshooting guide 2 Operator Warnings A This symbol marks specific safety warnings and operating procedures that are important for the safety of the Qball X4 and users Read these warnings carefully The Qball X4 is a powerful and potentially dangerous vehicle if used improperly Always Document Number 829 Revision 12 Page 1 Quanser Qball X4 User Manual follow safe operating procedures when using the Qball X4 Quanser is not responsible for damages and injury resulting from improper or unsafe use of the Qball X4 Before connecting batteries or attempting to run the Qball X4 be sure to read this document and become familiar with the safety features and operating procedures of the Qball X4 When handling the Qball X4 always make sure there are no models running and the power is turned off It is recommended that users wear safety goggles to protect the eyes Figure 1 Quanser Qball X4 Document Number 82
27. y are labeled 0 to 9 with the ground pins black wire on the servo cable located closest to the outer edge of the HiQ board Each motor speed controller should be connected in a specific order for the provided Qball X4 controllers to function Table 2 lists the motors and their standard corresponding servo channels Servo output channel Table 2 Motor servo channels The HiQ may have an optional daughterboard that contains additional I O such as receiver inputs 8 in Figure 7 sonar inputs 9 in Figure 7 and a TTL serial input used for a GPS receiver 10 in Figure 7 If the Qball X4 is provided with a sonar 15 in Figure 10 it should be connected to sonar input channel 0 as labeled on the daughterboard Document Number 829 Revision 12 Page 9 Quanser Qball X4 User Manual 5 3 3 Qball X4 Power The Qball X4 uses two 3 cell 2500mAh LiPo batteries 14 in Figure 9 to power the HiQ and motors These batteries are held in place below the center of the frame using two velcro straps The batteries should be stacked vertically and aligned with the aluminum plate on the bottom side of the frame and secured tightly with the velcro straps Make sure the batteries are firmly connected to the frame before attempting to fly the Qball X4 Secure the batteries to the frame before connecting the batteries to the Qball X4 battery connectors 12 in Figure 8 and always turn off the power using the switches 11 in Fig ure 8 before cha
Download Pdf Manuals
Related Search