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BME 290 Final Report - Biomedical Engineering

1. 9 Possible values for R2 and C are 2maR 1820Q and 2 2uF The signal will be sent to a non inverting amplifier to be amplified and then passed to the microprocessor where it will be analyzed and sent to an LCD screen to be displayed Fig 5 THERMISTOR RTI x R2 C U2 AW i i 1 82 2 2u Vo to microprocessor Differential Amp R4 Figure 13 Thermometer Circuit Values for R3 and R4 will be determined from gain equation for non inverting amplifiers V R O MEL TES NES Vin R The target gain for the amplifier will be based on the input current or voltage for the microprocessor 28 The thermometer will be tested by placing the probe in a beaker of water heated to a certain temperature and comparing the resulting temperature given by the thermometer to the actual temperature of the water This will be done over a range of temperatures to determine the thermometer s actual operating range and to assure that is within the appropriate range to measure body temperature We feel an appropriate temperature range to test this would be from 29 C to 43 C It will be made sure not to test with a temperature so hot that it burns the thermometer Final testing will be done by taking group members temperature with the thermometer and comparing the reading with that taken by a commercial digital thermometer 2 2 2 2 Pulse Oximeter To measure blood oxygen saturation a pulse oximeter will be used Pulse oximetry us
2. Attn Project Name Accessible Home Vital Signs Monitor ONLY ONE COMPANY PER Lab Admin only FRS Student Initial Budget Student Current Budget Project Sponsor REQUISITION Catalog Description Unit Unit Price 568 1091 5 ND Philips USB Chip PDIUSBD12 3 49 497 1382 5 ND Linear Voltage Regulator 3 11 Comments Price Quote File Name Yes or No Vendor Accepts Purchase Orders Vendor Digi Key Corporation Address www digi key com 701 Brooks Avenue South Thief Rivers Falls MN 56701 Phone 1 800 433 4539 Contact Name 76 Shipping Total Authorization PURCHASE ORDER REQUISITION UCONN BME SENIOR DESIGN LAB Instructions Students are to fill out boxed areas with white background Date Each Vendor will req uire a different purchase requisition November 25 2006 Student Name Jenna Sullivan Team Total Expenses 2 000 Ship to University of Connecticut Biomedical Engineering U 2247 260 Glenbrook Road Storrs CT 06269 2247 Attn Project Name Accessible Home Vital Signs Monitor ONLY ONE COMPANY PER Lab Admin only FRS Student Initial Budget Student Current Budget Project Sponsor REQUISITION Catalog Description Unit Unit Price CVS Arm Cuff Large 9 99 Vicks Speed R
3. 2 1day Fri 1 26 0 Fri 1 26 07 83 3 Weekly Report Wk 3 1day Fri 2 2 05 Fri 2 2 05 84 3 Weekly Report Wk 4 1day Fri 2 9 05 Fri 2 9 07 85 3 Weekly Report Wk 5 1day Fri 2 16 07 Fri 2 16 07 86 3 Weekly Report Wk 6 1day Fri 2 23 07 Fri 2 23 07 87 Weekly Report Wk 7 1 day Fri 3 2 05 Fri 3 2 07 88 E Weekly Report Wk 8 1 day Fri 3 16 07 Fri 3 16 07 89 E Weekly Report Wk 9 1 day Fri 3 23 07 Fri 3 23 07 90 E Weekly Report Wk 10 1 day Fri 3 30 07 Fri 3 30 07 91 E Weekly Report Wk 11 1 day Fri 4 6 05 Fri 4 6 05 92 E Weekly Report Wk 12 1 day Fri 4 13 07 Fri 4 13 07 93 E Weekly Report Wk 13 1 day Fri 4 20 07 Fri 4 20 07 94 E Weekly Report Wk 14 Final 1 day Fri 4 27 07 Fri 4 27 07 95 Write Owners Manual 20 days Mon 4 2 0 Fri 4 27 07 96 E3 Make sure useris properly electrically isolated from monit Q1day Mon 4 16 0 Mon 4 16 0 97 3 Create Senior Design Day PowerPointPresentation 10 days Mon 4 9 07 Fri 4 20 07 98 E Senior Design Day 1day Fri 4 27 0 Fri 4 27 07 99 E Order any parts still needed 1day Fri 3 2 07 Fri 3 2 07 100 3 Troubleshoot complete vital signs monitor 5days Mon 4 16 0 Fri 4 20 07 64 8 Team Members Contributions to the Project Throughout the semester Team 3 met at least once a week to work on project design All papers and presentations were group efforts Each team member s specific work is described below Robert Croce Rob s main contributions were in the areas of processing and
4. Pressed Device Powers On Are the transducers m O Hold connected to the patient Begin heart rate BP pulse oximetry and Button Begin blood temperature Pressed pressure readings readings Record Stop button pressed Record readings to USB flashdrive Record Stop button pressed Readings stop recorded to USB flashdrive Figure 10 Flowchart of Accessible Vital Signs Monitor Operation 2 2 2 Subunits 2 2 2 1 Thermometer To measure body temperature a thermistor circuit will be used The thermistor will be in the form of a commercially purchased oral temperature probe The probe we have chosen for this is the Welch Allyn 02893 000 Sure Temp 690 Oral Probe from DREMed com for a cost of 74 00 before shipping and tax Fig 11 26 http www dremed com catalog product info php products 1d 1214 Figure 11 Welch Allyn Sure Temp 690 Oral Temperature Probe The thermistor within the probe will convert changes in temperature to changes in voltage Unfortunately thermistors are inherently non linear The Steinhart Hart equation describes the resistance temperature curve of a thermistor 17 Z a bin R cln R where T is the temperature in kelvins R is the resistance in ohms and a b and c are constants called the Steinhart Hart parameters which will be provided by the thermistor manufacturer This output can be linearized through the use of a Wheatstone bridge Fig 12 THERMIS TOR
5. This is done by wrapping a blood pressure cuff around the upper arm and inflating it until the pressure around the arm due to the cuff collapses or occludes the brachial artery The cuff is then slowly deflated As the cuff deflates blood starts pumping through the brachial artery causing minute vibrations of 5 to 1 mmHg in the cuff 4 The pressure at which these vibrations start is the systolic pressure and the pressure at which they stop is the diastolic pressure 5 The block diagram in Fig 26 illustrates how this method will be used to measure blood pressure in the accessible vital signs monitoring system Each system in the flow chart is described in more detail in the following paragraphs When the blood pressure Start button on the vital signs monitor is pressed the blood pressure cuff will be inflated to about 40mmHg above normal 160mmHg The blood pressure cuff used will be a DRE Adult single lumen cuff from DREMed com at a cost of 37 00 before shipping and tax Fig 23 35 Si 3 so 2 Q0 427 2006 iaia Nr na 2644 TM http www dremed com catalog product info php cPath 56 121 241 242 products id 194 Figure 23 DRE Adult Single Lumen Blood Pressure Cuff The cuff will be inflated by a Sensidyne AA Series Micro Air Pump A microprocessor second to the microprocessor controlling the rest of the device will control the inflation of the cuff The sensor used to sense cuff pressure will be the NPC 1210 low pressure
6. sensor from GE Once the pressure sensor determines that the cuff has been inflated to 160mmHg the cuff will deflate slowly at a rate of 2 3mmHg sec Deflation will occur through a release valve brand to be determined A basic circuit for the automated blood pressure system is seen in Figure 24 The pump and valve are powered by the battery and controlled by the microprocessor The pressure sensor also receives power from the battery and it sends signals to the microprocessor Amplifier resistor values R1 and R2 will be determined experimentally Cuff V from microprocessor RE RE vo to microprocessor from batte n Figure 24 Automated Blood Pressure System Circuit As blood begins flowing through the brachial artery again it will cause small pulsations that will be picked up by the pressure sensor in the cuff Fig 25 This waveform will be analyzed by the microprocessor to determine the systolic and diastolic pressures 36 Vo Volts Time seconds Figure 25 Blood Pressure Waveform Picked Up by Pressure Sensor 17 Where MAP Maximum Arterial Pressure SBP Systolic Blood Pressure DBP Diastolic Blood Pressure A threshold voltage level will be set This will be done by experimentally comparing blood pressure readings from a sphygmometer or other commercial device to those detected by our pressure sensor Once 4 pulsations peak above the threshold level the voltage will be recorded and from tha
7. 0 Wed 2 4 0 40 E Write therm om eter code for Blackfin 05 days Mon 1 22 0 Mon 1 22 0 41 E Write pulse oximeter code for Blackfin 1day Mon 2 12 0 Mon 2 12 0 42 E Write heart rate code for Blackfin 3days Wed 2 14 07 Fri 2 16 07 43 E Write blood pressure code for Blackfin 5days Wed2 21 0 Tue 2 27 0 44 3 Write respiratory rate code for Blackfin 1day Wed2 28 0 Wed 2 28 0 45 E Write scale code for Blackfin 05days Mon 1 29 0 Mon 1 29 0 46 E Build voltage regulator circuits 1 day Fri 2 16 05 Fri 2 16 07 47 E Set up device power source A C jack 2 days Fri 2 16 07 Mon 2 19 0 48 E Build recharge circuit 5days Mon 2 19 0 Fri 2 23 07 49 E Testrecharge circuit 2days Mon 2 26 0 Tue 2 27 0 48 63 ID TaskName Duration Start Finish Predecessors Resource Names 0 bn aaa 50 3 Test Bluetooth m odule 3days Mon 2 26 0 Wed 2 28 0 51 E Write code for Bluetooth module 2 days Fri 3 2 07 Mon 3 5 05 52 E Test Bluetooth dongle 1day Mon 3 12 0 Mon 3 12 0 53 E Test complete Bluetooth system for device 3days Wed3 4 0 Fri 3 16 07 54 E Build cohesive vital signs monitor 5 days Fri 3 16 01 Thu 3 22 0 55 3 PCB design 18 days Thu 3 1 07 Mon 3 26 0 56 3 Order PCB 1day Tue 3 27 0 Tue 3 27 0 55 57 3 Case design 18 days Thu 3 1 07 Mon 3 26 0 58 E3 Order case 1day
8. 4 displays from Crystal Fontz will be used These displays are the same ones used in Design 2 Each measures 122mm x 44mm with a viewing area of 99mm x 24mm and a character height of 8 06mm The same process and parts to produce audio process in Designs 1 and 2 will also be used in this design The Magnevation SpeakJet IC will be used in conjunction with the TTS256 Text to Code IC to produce speech To play these sounds and the alarm a commercial 5W 8 Ohm speaker will be purchased The alarm will include audio and visual features that will turn on when the patient s vital signs become abnormal 2 2 Optimal Design 2 2 1 Objective Due to the increasing number of chronic illnesses along with the shortage of nurses home monitoring is becoming more and more of a necessity Patients that require frequent healthcare monitoring can now have this done in the comfort of their own home An important tool for home health monitoring is the vital signs monitor Our accessible home vital signs monitoring system will have the capability to non invasively gather a patient s heart rate blood pressure blood oxygen level body temperature weight and respiratory rate and then send this data to their corresponding healthcare provider To send this data we will create a password protected encrypted website to which patients can upload their vital signs This accessible home vital signs monitoring system design is an accurate and consistent way to obtain a pa
9. 5V R because LEDs usually need 1 5V to turn on 12V TU e Figure 16 Circuit for Constant Current LED Driver To control the pulsing of the LEDs a timing circuit needs to be used For this we will use a 555 timer circuit Fig 17 The 555 timer will supply 50us pulses to the LEDs atarate of 1 kHz This is well above the maximum frequency in the arterial pulse which is never more than a few Hz 4Vcc R1 8 VCC p ul TRIGGER RESET OUTPUT 6 CONTROL THRESHOLD ESE DISCHARGE Figure 17 Timing Circuit The values of the resistors can be determined from T 2 7 R R C and T 7R C 31 where T is the pulse length 50us and T is the rate IKHz or 1ms Thus values for R1 R2 and C2 are 56kQ 3 3kQ and 22nF respectively The 10nF capacitor connected to the control will be used to eliminate any electrical noise from the timer Finally an n channel enhancement mode MOSFET connected across the each LED is used to pulse the output from them Fig 18 R1 OPAMP Ho cit DS135C Figure 18 Circuit to Pulse the LEDs In the receiving end of the circuit is the photodetector The photodetector used in pulse oximetry probes is a photodiode The photodiode detects the light transmitted through the finger as current 16 To amplify the signal the photocurrent must be converted into a voltage with moderate output impedance This can be done by using an op amp configured for current
10. A REPE ER 43 Table Design Bud Sette c vo HOT OH UY S DE PRSE TENE MA GS 62 Table 4 Project Dune leas coca la caia A VEO wus sulle oh EAAS 63 64 Abstract The Accessible Home Vital Signs Monitoring System is a project funded by the Rehabilitation Engineering Research Center on Accessible Medical Instrumentation s RERC AMI National Student Design Competition This device has been designed to be accessible for clients of different abilities and ages The Accessible Home Vital Signs Monitoring System that we have designed measures blood pressure blood oxygen saturation heart rate temperature weight and respiration rate In this system these vital signs are displayed on a monitor and saved to a USB flashdrive Through a secure website that is part of the system the client can upload their vital signs from the flashdrive via any Internet connected computer This allows clients to communicate their health status to physicians and healthcare providers anywhere in the world Accessibility is provided through large well lit LCD screens a speaker system and Braille customized buttons Vital signs are displayed on large LCD screens as well as spoken through a speaker system An included alarm system to alert the client of abnormal vital signs uses both visual lights and auditory sound cues A simple 3 button design provides an easy to use user interface appropriate for all age levels and technological savvy Also all buttons are customized wi
11. ALL RB 9V S250 SP01 9V Rechargable Battery 17 64 0 00 0 00 0 00 0 00 0 00 0 00 Comments Price Quote File Name Yes or No Vendor Accepts Purchase Orders Vendor Open Tip Address www opentip com Phone 1 888 882 8232 Contact Name 73 Shipping Total Authorization PURCHASE ORDER REQUISITION UCONN BME SENIOR DESIGN LAB Instructions Students are to fill out boxed areas with white background Each Vendor will require a different purchase requisition Date November 25 2006 Student Name Michael Kapinos Team Total Expenses 2 000 Ship to University of Connecticut Biomedical Engineering U 2247 260 Glenbrook Road Storrs CT 06269 2247 Attn Project Name Accessible Home Vital Signs Monitor Lab Admin only FRS Student Initial Budget Student Current Budget Project Sponsor ONLY ONE COMPANY PER REQUISITION Catalog Description Unit QTY Unit Price Amount SC 200 Homemedics Digital Bathroom Scale 1 19 95 19 95 0 00 Comments Price Quote File Name Yes or No Vendor Accepts Purchase Orders Vendor Whole Sale Point Address www wholesalepoint com Phone 1 800 986 0525 Contact Name Total 19 95 Author
12. Cefotaxime Treatment Results with a Computerized Ambulatory Drug Delivery System The American Journal of Medicine 97 no 2A 1994 50 55 Note The estimated hospital cost day patient is 417 and the estimated savings day patient is 262 These costs were multiplied by 30 days reflecting the above per patient per month costs Figure 46 Table of Home Care Cost Savings 2 When patients choose or have the option to enter home care they free up hospital beds for more acute cases give doctors more time to work with sicker people and many times the patients themselves are happier at home than in the hospital But patients cannot be cared for at home unless they have the proper technology to do so Our accessible vital signs monitoring device is a simple easy to use method to monitor patients health at home It can be operated by patients their families and physicians making it an ideal device for the home environment Since vitals signs are saved on a USB flashdrive to be uploaded to a secure website patients are not even stuck at home but can take their rechargeable battery powered vital signs monitor with them if they need to monitor their vital signs This offers flexibility and comfort to patients Economically the design for our device will reduce some of the costs of healthcare Vitals sign monitors and many of these are not accessible currently range in cost from 2500 up to 5000 Most of the monitors that me
13. Core Cycye Period VDDINT 1 2V 5 4 76 200 ns tCCLK1 1 Core Cycye Period VDDINT 1 1V 5 5 56 200 ns tCCLK1 0 Core Cycye Period VDDINT 1 0V 5 6 67 200 ns Operating Voltage 1 425 1 575 V 2 2 2 7 LCD Screens The digital information from the output of the microcontroller will be sent to six character LCD screens Fig 33 43 http www crystalfontz com products 16021 CFAH1602L YYH JP_ front bl onjpg Figure 33 LCD Screen The CFAHI602L GGH JP LCD screens are ideal for our design due to its easy to read characters ideal size and wide viewing angles It measures 122mm x 44mm with a viewing area of 99mm x 24mm and a character height of 8 06mm These LCD screens were chosen due to the fact that many of the features meet the specific needs of our clients Since the majority of our clients will be viewing the monitor from their bed it is important that the screens should be viewable from a wide variety of angles Since these screens have a wide viewing angle patients will have no problem seeing their vital signs from their bed Also the yellow backlight makes this LCD screen easy to read especially in dark or dim lighted areas Also a viewing area of 99mm x 24mm makes the screens easy to read from a distance 2 2 2 8 Speech Output Our vital signs monitor will contain a text to speech function which will allow the monitor to say what the vital signs are once they have been recorded This function will be useful for our clien
14. addresses compatible with the Magnevation SpeakJet Speech Synthesizer IC The commercial speaker we have chosen to play these sounds is a simple small 5W 8 Ohm speaker which will also act as part of the alarm The alarm will include audio and visual features that will turn on when the patient s vital signs become abnormal 2 1 2 8 USB Device and Secure Website Vital signs readings will be stored via a USB flashdrive through the same system describe in Design 1 The USB device that we decided to use is the Philips PDIUSBD11 By writing a computer program in the microprocessor we will be able to send the data received by the machine to the USB device and then to the computer After the patient s vital signs have been gathered and recorded they need to be sent to their primary healthcare provider To maximize patient privacy we have devised a way to securely transmit the patients health information minimizing the risk of interception We will create an encrypted password protected website to which the patient uploads the information from their USB stick To ensure that the website is secure HTML encryption software will be used to encrypt the contents of the website allowing only those with the correct username and password to access it We will use encryption software such as TagsLock Pro v 2 22 to hide the source code of our HTML documents To encrypt HTML using TagsLock PRO you need to create a new project once and re use it later whe
15. addresses compatible with the Magnevation SpeakJet Speech Synthesizer IC This IC is Compatible with Basic Stamp OOPic PIC and any processor with a serial port like our microchip 13 To play these sounds a commercial speaker will be purchased For our purposes we chose a simple small 5W 8 Ohm speaker to generate all our speech sounds as well as the alarm The alarm will include audio and visual features that will activate when the patient s vital signs become abnormal 2 1 1 6 USB Device and Secure Website Vital signs readings will be stored via a USB flashdrive This device will then be connected to a computer in which it is possible to send the readings to any computer that has an Internet connection The USB device that we decided to use is the Philips PDIUSBD11 This device uses I2C technology to connect to the microprocessor This allows for easy communication between the two By writing a computer program in the microprocessor we will be able to send the data received by the machine to the USB device and then to the computer After the patient s vital signs have been gathered and recorded they need to be sent to the primary healthcare provider We will create an encrypted password protected website to which the patient can upload the information from their USB stick To ensure that the website is secure HTML encryption software will be used to encrypt the contents of the website allowing only those with the correct username and p
16. converted and processed by the microprocessor Like the thermistor circuit the thermocouple circuit will also include a Wheatstone bridge Fig 28 Values for the resistors R will be decided experimentally 39 Thermocouple RTI LPF vb to microprocessor e Figure 28 Circuit for Respiratory Rate As mentioned previously this circuit will be calibrated experimentally Voltage output from the thermocouple will be measured for inspiration and expiration most likely from being tested on group members From these measurements voltage thresholds will be set for inspiration and expiration Experiments will also be done to determine the optimum time period for measurement Testing will be done by comparing the readings from our respiratory rate monitor to those taken by the Biopac respiratory belt from the Biopac software used in the ENGR 166 lab 2 2 2 5 Weight Weight is an important vital sign to monitor In addition to ensuring proper eating habits weight is used to determine medication doses We will include weight monitoring into our vital signs monitor by buying a digital scale that exists on the market and connecting it to our device The scale that will be used is the Homedics SC 200 Digital Scale Fig 29 y DIGITALSCALE c Figure 29 Homedics SC 200 Digital Scale This scale was chosen because it fits quite well with our project We figured with our clients we will have to build handles onto the scal
17. displays As the project began he began looking into which microprocessors would be suitable for the specific information that had to be processed At first the highly popular PIC16F877 Microchip seemed like it would handle the majority of the operations in the design As more research went into the design it was concluded that either multiple processors or one large processor would be needed The Blackfin Digital Signal processor was then chosen Since then Rob has continued to learn about this latest digital processor He has been working on LabVIEW code which will be used to program this processor He has also revisited the Biosignals class to reread FIR and IIR filters which will be used in filtering the incoming signals form the patients body These filters as well as the analog to digital converters can be found in the LabVIEW Embedded Module for Analog Devices Blackfin Processors software He also researched the display units and speech chips and has been working on sending the information to these units as well as the initial prototype of the respiratory rate design Rob also considered the casing of the unit Currently a method of constructing a case using an AutoCAD drawing is being researched Michael Kapinos Mike was in charge of dealing with a few of the different features incorporated in the home vital signs monitoring system Mike did research on the use of the USB port which allowed an easy way to be found to send the date from
18. hettnORIEtet olio cseeentncidds 21 3 3 P lse OXimeter ec e eI e EE A n SIR RE 2 1 3 4 Non Invasive Blood Pressure 2 1 3 5 Respitatory Rate usi era x ERE ERREUR YR d 2 1 5 6 WSIS o A easet mes 2 1 3 7 Secure Email System dese 2 1 3 8 Power Supply sssssssssss 2 1 5 9 Bluetooth tidad 2 13 10 PUSADUONS e debeo Er orte res 2 1 23 D AGG o eirca noua ESL ee ens 2 1 3 12 Processing Display and Alarm 2 2 Optimal Deidad Ped he A A A bien epe A 24 26 2 2 2 ISUDUTH ssl ail pedit ae vos deaur da 26 54 2 2 2 1 Lhetmorielets s oos o M ea E OX ORE CHI ea ban 26 29 2 23 Pulse OXimeter res cata Wleaaae oo RR A 29 35 2 2 2 3 Non Invasive Blood Pressure c0ceeeeees 35 39 22 24 Respiratory Ratezscss etu ERO bt ierra 39 40 2229 AVETE ieri re DS Ar ERR E Me ROS E NREN AN SQUE 40 41 2 2 2 0 MIGr DFOCeSSDE cordes ep cen RR D ep 41 43 22 2 ECD IS rone ba neto e n RUN SEX Eheu RSEN 43 44 22728 Speech OUDDUL centers he pem conceansmorhaamaaaiacgcenind 44 46 22 259 TOTO a n ORDEI a ORI ere ee Lone 46 47 2 22 T0 Secure Website ood ees hoe eroe o ve a dnas 47 22 0 11 Power Supply den E S s 47 48 22 2 12 ISB Device uias SERRE OMA a Fa heces ule 48 49 22 2 AS Bluetooth uo eot RERO ERUIT REA EEEa 49 50 2 2 2 VA PUShbDUltOBS eis as eda Re otl d Ia IRR e ts She Eom 50 51 2 22 18 O ERU 51 53 2 2 2 16 Accessible Vital Signs Monitor Circuit Diagram 54 37 Realisti CONSTE ooo Lose od Ore
19. oral temperature probe the thermistor needs to be linearized calibrated around 98 6 F 37 C for a temperature range of at least 90 104 F 32 40 C After being linearized the signal will be sent to a low pass filter to remove any noise The signal will be sent to a non inverting amplifier to be amplified and then 12 passed to the microprocessor where it will be analyzed and sent to an LCD screen to be displayed The thermometer will be tested by placing the probe in a beaker of water heated to a certain temperature and comparing the resulting temperature given by the thermometer to the actual temperature of the water Final testing will be done by taking group members temperature with the thermometer and comparing the reading with that taken by a commercial digital thermometer 2 1 2 3 Pulse Oximeter To measure blood oxygen saturation a pulse oximeter will be used The pulse oximeter finger probe that we will use is the DRE Datascope compatible SpO2 finger probe for 165 00 price before shipping and tax from DREMed com It contains two LEDs one that works at a red wavelength and the other at a near infrared NIR wavelength Also in the probe is a photodetector that will detect the light transmitted through the finger 16 Like in Design 1 to transmit light the LEDs need to be driven by a constant current source This can be done by a non inverting op amp combined with a FET To control the pulsing of the LEDs two 555 timers wi
20. our project Rehabilitation Engineering Research Center on Accessible Medical Instrumentation RERC AMI National Student Design Competition Provided Funding Dr John Enderle Client Contact and Advisor Bill Pruesner Advisor Dave Price 12 Appendix 12 1 Updated Specifications Mechanical Weight unit without peripheries lt 6 pounds Size 20cm x 10cm x 20cm max handle for transport Button size 15mm x 20mm Durability Able to transported and withstand minor bumps and disturbances Water Resistance Recommend avoid water and spills Anchoring Mounting Rubber treads on bottom of device 68 Electrical Power Source Back up battery Display Height Width Illumination Data Output Temperature Measurements Scale Range Accuracy Response Time Pulse Oximetry Saturation Range Accuracy Heart Rate Range Accuracy Non invasive blood pressure NIBP Cuff Pressure Range Measurement Time Respiratory Rate Range Measurement Time Weight Scale Type Range Hardware and Software Parameters Microprocessor Programming Language Environmental 120V AC Rechargeable 9V NiCd 20cm max 40cm max Back lit LCDs Standard USB port Bluetooth Wireless Transmission Fahrenheit F 90 110 F 2 F 10 seconds oral 94 98 t3 80 250bpm 3bpm 0 160mmHg lt 60 seconds 0 60 breathes per min 30 seconds Digital TBD Analog Devices Blackfin DSP LabVIEWTM 69 Location Home indoors Dus
21. scence eee e cent eee eneeeaeaees 21 9 Mustration OF D6Sigticu sd at 25 10 Flowchart of Accessible Vital Signs Monitor Operation c cesses eee 26 11 Welch Allyn Sure Temp 690 Oral Temperature Probe eceeeceeeeee neon es 27 12 Thermistor Linearizing Circuit Optimal Design ccc cece cence eee e ee eee 2T 13 Thermometer CU 28 14 Pulse Oximeter Circuit Block Diagram uec eo ye So Te Ee a o Rosie ak t 30 15 Finger Probe Diagram Optimal Design ooooooconcccononnccocancconconcrononanano 30 16 Circuit for Constant Current EBD DAVE eise ei oed EE EE RPa Co UetoRe dus 31 T7 IO CU e cbe eoo e RE er eb ry o e b x edid eta tuas 31 18 Circuit to POlse te BINS 002259 ease roo ratero 32 19 Current to Voltage Photodiode Conversion Circuit cceceeeeeeeeeee ence eens 32 20 SamplecandsHOoRL Circuit a ecis iie eetet ed rye pe tO LER UEFA eaves po DRUEROOE AERE RE aes 33 21 Pulse Oximeter Circuit DIaUtatmoss os Sade EE EE OW o E DURO TEE as 34 22 Pulsatile Signals Found in the Intensity of Detected Light seuueuuuusu 35 23 DRE Adult Single Lumen Blood Pressure Cuff oooococcccccncconconccnncncncnncnnnos 36 24 Automated Blood Pressure System Circuit cesses 36 25 Blood Pressure Waveform Picked Up by Pressure Sensor sessussse 37 26 Block Diagram of Automatic Blood Pressure Optimal Design 38 27 Image of The
22. the computer as in previous designs We also explored an effective way to enclose the inner circuitry of our device in this design An AutoCad drawing of our casing will be sent to Toolless Plastic Solutions who will take that file and manufacture a plastic casing Buttons will be customized to increase accessibility and ordered through Grayhill Co Finally in this design we have included a method to transmit the vital signs data to the healthcare professional through a secure e mail system rather than a website 2 1 3 2 Thermometer Like in Designs 1 and 2 to measure body temperature a thermistor circuit will be used The probe chosen for this is the Welch Allyn 02893 000 Sure Temp 690 Oral Probe from DREMed com as in Design 2 For our use as an oral temperature probe the thermistor needs to be linearized calibrated around 98 6 F 37 C for a temperature range of at least 90 104 F 32 40 C After being linearized the signal will be filtered amplified and then passed to the microprocessor where it will be analyzed and sent to an LCD screen to be displayed as in Design 2 The thermometer will be tested by placing the probe in a beaker of water heated to a certain temperature and comparing the resulting temperature given by the thermometer to the actual temperature of the water We feel an appropriate temperature range to test this would be from 32 C to 40 C Final testing will be done by taking group members temperatur
23. the microprocessor to a local health care provider His research made it so that while using the USB portion of the device it will be easier to use a PIC microprocessor to take away some of the load that the Black fin will be carrying Mike was also in charge of researching the power supply and rechargeable batteries By meeting with a senior in the Electrical Engineering department he learned how to connect the power supply to the device and how to break it down so the transducers will not use too much voltage Mike was also in charge of selected buttons that best fit with the device These buttons needed to be easy to push down and also include Braille Mike was in charge of selecting a digital scale that will easily be incorporated into the device Aside from the above features Mike also wrote some of the project documents and presented a portion of the projects proposal Jenna Sullivan Jenna worked mainly on the transducers and their circuitry She is responsible for all of the research design and part selection of the thermometer pulse oximeter blood pressure and respiratory rate except Design 2 where Rob researched the respiratory belt devices In addition to this Jenna was responsible for the Bluetooth wireless option seen in Design 3 and the Optimum Design She created the final circuit diagram of the vital signs monitor and did much of the writing in the project reports She also integrated 65 the sections of the final report into
24. 000 seniordesign E File Edit View Insert Format Tools Draw Dimension Modify Window Help z Bix DOSE SQQ BAX Soe See KeTetneaa mea AAQQagag SS PEF mo v El Color 40 v ByLayer X ByLayer y ByLayer M j mg S TEGS A iFmacgkes5rj pda amp a soronmiobSxNxs SNAP GRID ORTHO POLAR OSNAP OTRACK LwT MODEL 2 AOL Inst v GM After our La cay contribution Y Document2 kfin Paint AutoCAD 20 Q amp A 12 40 PM Figure 42 Preliminary AutoCad Illustration of Casing 53 2 2 2 16 Accessible Vital Signs Monitor Circuit Diagram Elcon Boxma Figure 43 Accessible Vital Signs Monitor Circuit Diagram The previous figure combines all of the above subunits into a circuit diagram This is a basic diagram of our complete vital signs monitor Fig 43 54 3 Realistic Constraints The main source for medical instrumentation standards is the Association for the Advancement of Medical Instrumentation AAMI They provide for purchase the current standards of medical device design and use These standards must be followed in the design and production of our device to ensure that it is acceptable and safe for our clients and the health care community This device has been designed with the economic constraint of cost in mind We have a maximum budget of 2000 to build a working prototype of our device so parts were chosen carefully A balanc
25. 1 1 2 Thermometer To measure body temperature a thermistor circuit will be used The thermistor will be in the form of a commercially purchased oral temperature probe brand to be determined It will convert changes in temperature to changes in voltage Thermistors are inherently nonlinear so to linearize the output of the thermistor it will be placed in series with a resistor 9 The value of the resistor will be determined from the resistance of the thermistor at room temperature and data from the temperature probe spec sheet For our use as an oral temperature probe the thermistor needs to be linearized for temperatures from 90 104 F 32 40 C After being linearized the signal will be sent to a low pass filter to filter out any noise and then passed to a non inverting amplifier to be amplified Finally the signal will be sent to the microprocessor where it will be analyzed and passed to a LCD screen to be displayed 2 1 1 3 Pulse Oximeter To measure blood oxygen saturation a pulse oximeter will be used Pulse oximetry uses the optical properties of blood to determine blood oxygen saturation Our pulse oximeter will have two parts a finger probe and the oximeter circuitry The finger probe for the pulse oximeter will be commercially purchased brand to be determined It will contain two LEDs one that works at a red wavelength and the other at a near infrared NIR wavelength Also in the probe will be a photodetector that will dete
26. 12 75 Crystalfontz LCD screens 1 1 Blackfin Processor 23 63 Unknown Total 517 43 453 77 63 66 62 7 2 Timeline Project Timeline 1 100 Table 4 TaskName Duration Start Finish Predecessors Resource Names o 1 3 Order Parts Q1day Tue 1 16 0 Tue 1 16 0 2 E Make thermometer probe 2days Wed1 17 0 Thu 1 18 0 3 E Build therm om eter circuit 1 day Fri 1 19 05 Fri 1 19 07 4 E Test thermometer circuit 1day Mon 1 22 0 Mon 1 22 0 2 3 5 E Develop therm om eter voltage curve 1day Tue 1 23 0 Tue 1 23 0 23 4 6 E Learn Blackfin software 28 days Mon 12 18 0t Wed 1 24 0 7 Ej Blackfin development 12days Tue 1 16 0 Wed 1 31 0 8 3 Build pulse oximeter probe 2days Fri 1 26 07 Mon 1 29 0 9 E Test pulse oximeter probe 1day Tue 1 30 0 Tue 1 80 0 8 10 E3 Build puls e oximeter driver circuits 05days Wed 1 81 0 Wed 1 31 0 11 E Test pulse oximeter driver circuits 0 5 days Wed1 31 0 Wed1 31 0 10 12 E Build timer circuit 0 5 days Fri 2 2 05 Fri 2 2 01 13 E Test timer circuit 0 5 days Fri 2 2 05 Fri 2 2 07 12 14 E Build sample and hold circuits 0 5 days Mon 2 5 07 Mon 2 5 07 15 E Testsample and hold circuits 0 5 days Mon 2 5 07 Mon 2 5 07 14 16 E Complete pulse oximeter circuit 1 day Wed 2 7 01 Wed 2 7 0 17 E Test pulse oximeter circuit 1 day Fri 2 9 05 Fri 2 9 01 18 E3 Calibrate pu
27. 662 3500 Contact Name 78 PURCHASE ORDER REQUISITION UCONN BME SENIOR DESIGN LAB Instructions Students are to fill out boxed areas with white background Each Vendor will require a different purchase requisition Date November 25 2006 Student Name Jenna Sullivan Team Total Expenses 2 000 Ship to University of Connecticut Biomedical Engineering U 2247 260 Glenbrook Road Storrs CT 06269 2247 Attn Project Name Accessible Home Vital Signs Monitor ONLY ONE COMPANY PER Lab Admin only FRS Student Initial Budget Student Current Budget Project Sponsor REQUISITION Catalog Description Unit QTY Unit Price MPX2200AP ND Sensor 1 12 78 Comments Price Quote File Name Yes or No Vendor Accepts Purchase Orders Vendor Digikey Address 701 Brooks Avenue South Thief Rivers Falls MN 56701 Phone 800 433 4539 Contact Name 79 Shipping Total Authorization PURCHASE ORDER REQUISITION UCONN BME SENIOR DESIGN LAB Instructions Students are to fill out boxed areas with white background Each Vendor will require a different purchase requisition Date November 25 2006 Team Student Name Robert Croce Total E
28. Earlier Discharge with Community based Intervention for Low Birth Weight Infants A Randomized Trial Pediatrics 92 no 1 1993 128 134 Bach J R Intinola P Alba A S and Holland LE The Ventilator assisted Individual Cost Analysis of Institutionalization vs Rehabilitation and In home Management Chest 101 no 1 1992 26 30 Field A I Rosenblatt A Pollack M M and Kaufman J Home Care Cost Effectiveness for Respiratory Technology dependent Children American Journal of Diseases of Children 145 1991 729 733 Close P Burkey E Kazak A Danz P and Lange B A Prospective Controlled Evaluation of Home Chemotherapy for Children with Cancer Pediatrics 95 no 6 1995 896 900 Note The study found that the daily charges for chemotherapy were 2 329 627 in the hospital and 1 865 833 at home These charges were multiplied by 30 days reflecting the above per patient per month costs Rich M W Beckham V Wittenberg C Leven C Freedland K and Carney R M A Multidisciplinary Intervention to Prevent the Readmission of Elderly Patients with Congestive Heart Failure The New England Journal of Medicine 333 no 18 1995 1190 1195 William D N et al Safety Efficacy and Cost Savings in an Outpatient Intravenous Antibiotic Program Clinical Therapy 15 1993 169 179 cited in Williams D Reducing Costs and Hospital Stay for Pneumonia with Home Intravenous
29. Final Report Accessible Home Vital Signs Monitoring System by Robert Croce Jenna Sullivan Mike Kapinos Team 3 Client Contact Dr John Enderle Director and Professor of Biomedical Engineering Program University of Connecticut Bronwell Building 260 Glenbrook Road Storrs CT 06269 2247 Phone 860 486 5521 Table of Contents ADS AC E er UE Ken A t Ne oa d UU ADU a RA T TIRECOQUCLION iu sre re ara ad IT Background accuse eco I DOR E ee 1 2 Purposeut Project nicotene ci EQUES EXEAT EEOERVS 1 3 Previous Work Done by Others ssssssssss EA A tae au nex eoe no POI didnt Hei A 1 3 2 Patent Search Results eter ta peto reete 1 4 Map for the Rest of the Report ooococccccccoccoccnccncnnos 25 Project Designa on E ep ead 2 1 Design AlternatiVeS i censere ee Ee exe e e n eda PUNTI NET 2 T ODISCUY itty ses iore epe eine umes 2 1 1 2 S ei cereos C eee rRNA 2 1 1 3 Pulse OM ras 2 1 1 4 Non Invasive Blood Pressure 2 1 1 5 Processing Display and Alarm 2 1 1 6 USB Device and Secure Website 2 1 1 7 Power SUPPLY os 2 12 WESTON e o toU 2121 ODIO GU Venu ooo ipd cene e vetet 2 1 2 2 a AAA O RARO bU de 2 1 2 5 PUSO 2 1 2 4 Non Invasive Blood Pressure 2 1 2 5 Respiratory Bates i see 21 246 Weill s A ke NENNEN 2 1 2 7 Processing Display and Alarm 2 1 2 8 USB Device and Secure Website 2 1 2 9 Power SUDDIVi n ias pais 21 3 Desig toda del 23123 ll Objectives core ous soo xU cause cd pru 2 1 3 2 E
30. IC microcontroller has a clock speed of about 20 MHz whereas the Blackfin has a clock speed of 350 MHz We will use the PF pins I O ports on microcontrollers on the Blackfin to function as inputs for the transducers and outputs for the LCD screens and speaker Due to the Blackfin s abilities it should be the only microprocessor we need for 16 our device The Blackfin can take C C code as well as LabVIEW Vi s Since we have had more experience using LabVIEW we feel that LabVIEW would be a more suitable code to program the processor After the data has been processed the information will be sent to 4 different areas the LCD displays the speech module the speaker and alarm For the LCD displays 4 displays from Crystal Fontz will be used These displays differ from our previous design due to the fact that they are a little larger making reading the displays easier for the patients Each display measures 122mm x 44mm with a viewing area of 99mm x 24mm and a character height of 8 06mm The same system as used in Design 1 will be used in this design to produce the audio output the Magnevation SpeakJet IC The SpeakJet will be controlled by a single I O line from the Blackfin 13 The TTS256 Text to Code IC will be used in conjunction with the SpeakJet The TTS256 is an 8 bit microprocessor programmed with letter to sound rules This built in algorithm allows for the automatic real time translation of English ASCII characters into allophone
31. RTI Wo 41 42 Differential Amp Figure 12 Thermistor Linearizing Circuit 11 Thus the resistance of the thermistor RT1 can be modeled by the first order equation 10 R T R I aT where R is the resistance of the other resistance in the Wheatstone bridge a is the temperature coefficient and AT is the change in temperature from the reference temperature AT T T in degrees Kelvin The reference temperature T o of the 27 thermistor is given by the manufacturer and for medical thermistors it is usually around 300 K The temperature coefficient a can be calculated from the following equation d R T _ adr _ P R T rd where f is a temperature constant typically around 4000 K 10 The value of the resistors R used to linearize the thermistor will be determined from the reference temperature and other values given by the manufacturer p or a using the above equations For our use as an oral temperature probe the thermistor needs to be linearized calibrated around 98 6 F 37 C for a temperature range of at least 90 104 F 32 40 C When linearizing the thermistor we must be careful to keep the accuracy of the thermometer high 1 C so as to be able to take appropriate measurements After being linearized the signal will be sent to a low pass filter to remove any noise The cutoff frequency for the filter should be less than 40Hz to remove any noise from room lights and other sources xi
32. Tue 3 27 0 Tue S3 27 0 57 59 E Research alarm parameters 5 days Mon 1 1 07 Fri 1 5 01 60 E Write alarm code for Blackfin 3 days Thu 2 1 07 Mon 2 5 07 61 E Solder parts to PCB 5 days Fri 4 6 07 Thu 4 12 07 56 62 E Put vital signs monitor together with casing and transduce 5 days Fri 4 13 01 Thu 4 19 0 63 E Test completed vital signs monitoring system 1 day Fri 4 20 05 Fri 4 20 07 64 E Develop secure website 25days Mon 2 26 0 Fri 3 30 07 65 E Test secure website 1day Mon 4 2 07 Mon 4 2 07 64 66 E Add button switches to appropriate circuits 1day Fri 3 16 05 Fri 3 16 07 67 E Update Website Week 1 1 day Fri 1 19 07 Fri 1 19 07 68 E Update Website Week 2 1 day Fri 1 26 01 Fri 1 26 07 69 E Update Website Week 3 1day Fri 2 2 05 Fri 2 2 0 70 E Update Website Week 4 1day Fri 2 9 05 Fri 2 9 0 71 3 Update Website Week 5 1day Fri 2 16 0 Fri 2 16 07 72 3 Update Website Week 6 1day Fri 2 23 0 Fri 2 23 07 73 E Update Website Week 7 1 day Fri 3 2 05 Fri 3 2 01 74 E Update Website Week 8 1 day Fri 3 16 07 Fri 3 16 07 75 E Update Website Week 9 1 day Fri 3 23 07 Fri 3 23 07 76 E Update Website Week 10 1 day Fri 3 30 07 Fri 3 30 07 77 E Update Website Week 11 1 day Fri 4 6 05 Fri 4 6 05 78 E Update Website Week 12 1 day Fri 4 13 01 Fri 4 13 07 79 E Update Website Week 13 1 day Fri 4 20 07 Fri 4 20 07 80 E Update Website Week 14 Final 1 day Fri 4 27 05 Fri 4 27 07 81 E Weekly Report Wk 1 1 day Fri 1 19 07 Fri 1 19 07 82 3 Weekly Report Wk
33. age No Regulation 260 Figure 30 Blackfin Image Package PBGA http www analog com images Product_Descriptions 60475542243306341558700011339bf535_hardware jpg Figure 31 EZ Kit Lite Evaluation Board 42 http www analog com images Product_Descriptions 3050239 1903402849 1184 682443 833402744562989117500usb_emulator jpg Figure 32 JTAG Emulation Like the traditional PIC Microchip the Blackfin ADSP BF535 processor contains timers which may be used to pulse the LEDs on our pulse oximeter This Blackfin contains 4 programmable timer units but only 3 of which are general purpose timers which we will use The general purpose timers can generate interrupts to the processor core providing periodic events for synchronization either to the processor clock or to a count of external signals 3 Since our LEDs will function as an external signal this general purpose timer can be used in assisting the pulsing of our pulse oximeter The general purpose pins are designated TMRO TMRI and TMR2 The timing requirements for the ADSP BF535 processor clocks are shown in the table below Table 2 Table 2 Core Clock Requirements Parameter Min Max Unit tCCLK1 6 Core Cycye Period VDDINT 1 6V 50 mV 2 86 200 ns tCCLK1 5 Core Cycye Period VDDINT 1 5V 5 3 33 200 ns tCCLK1 4 Core Cycye Period VDDINT 1 4V 5 3 7 200 ns tCCLK1 3 Core Cycye Period VDDINT 1 3V 5 4 17 200 ns tCCLK1 2
34. ard error of 30 percent or more Quantity zero l Age is the patient s age at the time of survey Numbers will not add to totals because a patient may be included in more than one category Total number of home health care patients includes manual and motorized wheelchairs Includes geri chairs lift chairs and other specialized chairs includes oxygen concentrator Figure 45 Excerpt from Table of Number of Current Home Heath Care Patients with Aides and Devices in 2000 12 58 As such it is important to have reliable technology to support home care Home care can not only save patients and insurance companies money Fig 46 but living at home can provide patients a welcome and comfortable environment in which to recover and be monitored Table 18 Cost of Inpatient Care Compared to Home Care Selected Conditions Per patient Per month Per patient Per month Per patient Per month Conditions Hospital Costs Home Care Costs Dollar Savings Low birth weight 26 190 330 25 860 Ventilator dependent adults 21 570 7 050 14 520 Oxygen dependent children 12 090 5 250 6 840 Chemotherapy for children 68 870 55 950 13 920 with cancer Congestive heart failure 1 758 1 605 153 among the elderly Intravenous antibiotic therapy for cellulitis 12 510 4 650 7 860 Osteomyelitis others Sources Casiro O G McKenzie M E McFayden L Shapiro C Seshia M M K MacDonald N Moffat M and Cheang M S
35. are electrically common then there cannot be any voltage dropped between them Even if the hot wire accidentally touches the metal casing it will create a direct short circuit back to the voltage source through the ground wire The patient s skin plays an important resistive role in protecting the body from such hazards But when the skin becomes wet or broken this resistive value drops to 196 of its original value putting the patient in serious harm if electrical safety precautions are not followed correctly 1 A circuit that is not properly grounded will have the potential to cause microshock Microshock is defined as the passing of high current from one body part to another such as from arm to arm and therefore directly through the heart Such high doses of current can cause difficulty breathing and even ventricular fibrillation 1 Choosing the correct gauge wire is also an important factor to consider An electrical hazard exists when the wire is too small a gauge for the current it will carry If a wire is too small for the current it is supposed to carry the wire will heat up The heated wire could have the potential to cause a fire inside the monitor After selecting the correct wire gauge it is important to make sure that all wires are properly insulated and cleanly soldered to their respective positions on the circuit board Frayed wires have the 57 potential to interact with other wires causing the monitor to not work properly
36. assword to access it We will use encryption software such as TagsLock Pro v 2 22 to hide the source code of our HTML documents In order to use this encryption software a website using the UCONN Biomedical Engineering server will be created 2 1 1 7 Power Supply When designing this project we found it rather important to include two different types of power The device will mainly be run from an external power source by using a power cord It will also be equipped with rechargeable backup batteries in case of a power failure For the power supply we plan on using a very generic universal power cord which will plug into the back of our device and then also plug into the wall For the backup power supply we determined the best way would be to use nickel cadmium rechargeable batteries Although lead acid batteries can sometimes produce more voltage nickel cadmium batteries are safer and will recharge a lot quicker The need for a backup battery is so the patient can take signs even if the power is gone 11 2 1 2 Design 2 2 1 2 1 Objective As with Design 1 our accessible home vital signs monitoring system will have the capability to non invasively gather a client s vital signs and transmit them to their healthcare provider To accommodate all users the monitoring system was designed to be as simple and user friendly as possible The following design differs from the first design in a few important ways First this new design is for a vital si
37. asure four of the same vitals 29 signs that our device does heart rate blood oxygen saturation blood pressure and temperature cost closer to 5000 If a patient s health insurance will not cover this cost than it becomes a large out of pocket expense for them or they may not be able to afford the device at all This is detrimental to their health and recovery By designing a monitor that s expected cost is 700 a third of the cost of the cheapest monitors currently available we will be able to alleviate some of this financial stress and provide more comprehensive health care and monitoring to more people Globally this design may translate into an affordable piece of medical equipment for undeveloped countries With its two button user interface detachable transducers and simple design it may be useful in countries with a low level of technology Our device is designed for home use but in countries and areas with poor healthcare systems and little to no medical equipment it would be useful in a hospital or emergency room Because it is lightweight and has a rechargeable battery and because vital signs are saved onto a USB flashdrive our accessible vital signs monitoring system is an excellent option for remotely monitoring patients in areas where there are few trained medical personnel A layperson with no medical training could use our device to visit a patient who does not have access to a hospital or doctor and record their vitals
38. be made Final testing of the device will be done by comparing its blood pressure readings to those ofa sphygmometer 2 1 3 5 Respiratory Rate Unlike Designs 1 and 2 respiratory rate in this design will be measured using a thermocouple The thermocouple will be clipped to the client s nose and will measure the change in temperature caused by inspiration and expiration Fig 8 The thermocouple will convert the changes in temperature it detects to changes in voltage Through experimentation voltages thresholds will be set to define the changes in temperature that correspond to inspiration and expiration By counting the number of inspiration and expiration pairs that occur in a given period of time we can determine respiratory rate Figure 8 Image of Thermocouple Nose Clip 21 The voltage from the thermocouple will be linear over our range approx 65 F to 98 F so the signal from the thermocouple only needs to be filtered and amplified before being A D converted and processed by the microprocessor As mentioned previously this circuit will be calibrated experimentally Voltage output from the thermocouple will be measured for inspiration and expiration From these measurements voltage thresholds will be set for inspiration and expiration Testing will be done by comparing the readings from our respiratory rate monitor to those taken by the Biopac respiratory belt from the Biopac software used in the ENGR 166 lab 2 1 3 6 Weight W
39. by using a power cord It will also be equipped with rechargeable nickel cadmium backup batteries in case of a power failure 2 1 3 9 Bluetooth Instead of using a USB device to move store patient data in this design we will transmit the data collected by the vital signs monitor to the client s computer wirelessly using Bluetooth We will purchase the EmbeddedBlue eb100 SER OEM Bluetooth Serial Module from A7 Engineering for 40 to integrate into our vital signs monitor to provide Bluetooth connectivity This module contains all the components of the Bluetooth stack on the board so that no additional host processor code is needed The interface between our host processor and the eb100 SER radio will be done through 22 UART communication Assuming that our clients computers are not Bluetooth ready a USB Bluetooth dongle will be purchased usually at 10 20 to provide connectivity on the PC end Our Bluetooth communications system will be calibrated through UART communication with any extra equipment necessary provided by the BME 252 lab It will be programmed to set up a network with the Bluetooth USB dongle when it detects it The Bluetooth system will be tested by acquiring vitals signs from the monitor and sending them to a computer in the design lab to which the USB dongle is installed The vital signs monitor will be placed at different ranges within 10 meters to determine signal strength at different ranges and the optimum range for data t
40. control circuit The gain control circuit adjusts the light intensity from the LEDs so that the d c level always remains at the same value whatever the thickness of the patient s skin tissue etc This circuit is implemented by feeding the d c signal to one input of a differential amplifier The other input to the amplifier is a constant reference voltage The output of the differential amplifier the voltage difference between the two inputs is used to generate the voltage that sets the value of the LED currents 16 The complete schematic Fig 21 of the pulse oximeter shows how each of the different circuits previously described will be integrated into a whole 33 Pm Red LED c R C ur B E 4TpF Vret D T ol OPAMP 34k 47uF e 2 al ny ur vret e v 34k 47UF B m SS OPAMP a gt t AHz NIR LED BPF 12V gt OPAMP Bs x rao a He microprocessor 2uF 44k 14k 22uF 12V OPAMP oy NAS E 22uF 44k 44k 224F Us 12V microprocessor Figure 21 Pulse Oximeter Circuit Diagram Calibration of the pulse oximeter will be done through the lookup table stored on the microprocessor Due to the scattering effects of blood Beer s Law does not apply for a pulse oximetry system 19 Therefore the blood oxygen saturation equat
41. ct the light transmitted through the finger 16 A non inverting op amp combined with a FET will be used to create a constant current source to drive the LEDs Two 555 timer circuits will be used to control the timing of the pulsing of the LEDs An n channel enhancement mode MOSFET connected across the each LED will be used to pulse the output from them In the receiving end of the circuit is the photodetector The photodetector used in pulse oximetry probes is a photodiode The photodiode detects the light transmitted through the finger as current 16 An op amp configured for current to voltage conversion will convert the photodiode detected current to voltage Sample and hold circuits are needed due to the pulse LED light to reconstitute the waveforms at each of the two wavelengths The timing circuits that were used to control the red and NIR LED drivers also are used to provide the control pulses for their corresponding sample and hold circuits 16 A simple sample and hold circuit can be created from a FET switch capacitor and op amp Once the signal goes through the sample and hold circuit it is sent through a band pass filter to eliminate noise then amplified and sent through an A D converter and the microprocessor to be analyzed A lookup table stored in the microprocessor will be used to calculate SpO gt values This signal is also sent through a low pass filter to extract the d c value of the transmitted signal which is then sen
42. determined This chip will be tested 44 experimentally by providing to it a series of inputs to confirm that it is giving the correct outputs http www speechchips com images SpeakJetIC jpg Figure 34 SpeakJet IC SJ TX TTS256 on JD Pp OH J_BUF_FULL RX http www speechchips com images tts256 gif Figure 35 Pin Diagram of TTS256 To play these computer generated sounds a speaker from Futurelec Fig 36 will be purchased and attached to the microcontroller This speaker was chosen due to its small size and affordable price This speaker will be used to play the data output from the 45 microprocessor as well as sound an alarm when the patients vital signs become irregular http www futurlec com Pictures Sm_Speaker jpg Figure 36 Small Speaker for Audio Output Features Small Size Power rating 0 5W Impedance 8 ohm Dimensions 50mm Diameter 16mm High 28mm base diameter 2 2 2 9 Alarm To assist our clients we will install an alarm system to alert them when their vital signs have become irregular or dangerous On top of the monitor will sit a light that will flash when these signs become abnormal A light we have chosen is shown below Fig 37 In addition an alarm sound generated by the SpeakJet will also serve as an alert The majority of the alarm design will be done by programming the microprocessor We will have a set of defined limits for each vital sign and if these s
43. e had to be maintained between using parts that meet the needs of our design and not overspending our budget It may be especially important to have room left in our budget next semester when we begin the actual construction of our device We may need to order replacement parts or additional parts as we go and we cannot do that if we have no money left within our budget Our accessible home vital signs monitor is meant for use in the home so varying environmental conditions are not a large concern of the device However being used in the home there were a few things we needed to keep in mind as we made our design Our device will be exposed to dust sunlight food and water Though it is not meant to withstand an onslaught of any of these things it was designed to be relatively robust in these conditions No parts were used that are very sensitive to movement or other household factors that could affect their use The device will have a durable plastic casing has been designed to withstand the typical rigors of home electronic life movement animals children cleaning spills etc That being said the device is not a toy nor was it designed to be one and the user should keep in mind the device s purpose when using it There are little to no concerns over our device s effect on the environment As it is a piece of home electronics it has very little effect on the environment as a whole Offshoots of the environmental constraints laid on our dev
44. e need to submit an AutoCad drawing of the final casing design Preliminary AutoCad drawings of the casing can be seen in Figs 41 and 42 Since we will not know the exact size and placement of all 6 holes for the LCD screens and the various I O ports in the casing the design will be submitted in the spring semester when all the parts have been ordered and more about the final design is known Toolless Plastic Solutions requires no tooling or molds and therefore will be a cost effective way to obtain an enclosure for our design 7 The company uses CNC Computer Numerical Control machining and fabrication process to build plastic casings We will not know the exact price of the casing until a design is sent for a quote 51 AutoCAD 2000 seniordesign ES x File Edit View Insert Format Tools Draw Dimension Modify Window Help O SE ena ranas HSB HHS KBTeneaag pray Qaqgaqgaqgag MEEF E v Er Color 40 ByLayer mail ByLayer y ByLayer X MENPSSHRY A SG BSE POSZHOSORONDCEUSNN v m P Enter option 2D wireframe 3D E Wwireframe Hidden Flat Gouraud fLat edges gOuraud edges Gouraud 3 Y Command 4 25 9557 6 4079 0 0000 SNAP GRID ORTHO POLAR OSNAP OTRACK LWT MODEL M ME 2 BOL Inst ib After our La ca contribution Y Document i9 blackfin Paint Y AutoCAD 20 JiS 12 41 PM Figure 41 Preliminary AutoCad Skeleton of Casing 52 AutoCAD 2
45. e so people will be able to hold on and not fall The reason for this is that some of our clients are elderly and might not be able 40 to stand steady on their own Also since this scale already has a main waist high base it should not be difficult to connect handles or rails The scale was also chosen because it is very inexpensive at 24 95 and it can be found at wholesalepoint com The scale has an on off switch and requires only one 9V batters for power As of now our main approach to connecting the scale to our device is a very simple and straight forward approach We plan on taking apart the scale and breaking the connection between the circuit and its digital display From here we just plan on simply connecting the scales circuit to one of our output displays instead The scale will already have been calibrated and tested by its manufacturer We will do additional testing by comparing known weight values dumbbells to the values displayed by the scale when we place the weights on it 2 2 2 6 Microprocessor The processor we are going to use for our design is the Blackfin ADSP BF535P Digital Signal Processor by Analog Devices Fig 30 This processor is extremely versatile due to the fact that it can function as both a microcontroller and a DSP Digital Signal Processor allowing for either 100 DSP 100 microcontroller or a combination of the two 8 This makes the Blackfin ideal for our design due to the fact that we are going to inpu
46. e will use encryption software such as TagsLock Pro v 2 22 to hide the source code of our HTML documents To encrypt HTML using TagsLock PRO you need to create a new project once and re use it later when the site content gets modified and needs re uploading In order to use this encryption software a website using the UCONN Biomedical Engineering server will have to be created for the prototype accessible home vital signs monitoring system 2 2 2 11 Power Supply When designing this project we found it rather important to include two different types of power The device will mainly be run from an external power source by using a power cord It will also be equipped with rechargeable backup batteries in case of a power failure For the power supply we plan on using a very generic universal power cord which will plug into the back of our device and then also plug into the wall For the backup power supply we determined the best way would be to use nickel cadmium rechargeable batteries Although lead acid batteries can sometimes produce more voltage nickel cadmium batteries are safer and will recharge quicker The need for a backup battery is so the patient can take their vital signs even if the power is gone Regarding the power source it will be in charge of taking power from an outlet in a wall and transferring that power into our system The type of power cord that we need to buy is a very basic cord which will change the A C power supply from t
47. e with the thermometer and comparing the reading with that taken by a commercial digital thermometer 2 1 3 3 Pulse Oximeter To measure blood oxygen saturation a pulse oximeter will be used The circuit design is the same as that from Designs 1 and 2 but unlike those previous designs the finger probe will be constructed instead of bought The block diagram of the pulse oximeter below shows an overview of the circuits that are involved and will be included in the vital signs monitoring device Fig 5 18 Sample and Bandpass filter Amplifier hold circuit Current to Sample and hold circuit LCD screen A D converter Microprocessor Bandpass filter Amplifier Photodiode detector ux NIR LED driver Red LED driver circuit circuit Automatic gain Automatic gain control circuit control circuit Low pass filter Low pass filter Figure 5 Pulse Oximeter Circuit Block Diagram Timing circuit Timing circuit To build the finger probe that we will use with our device we will need a red LED a NIR LED and a photodiode The LEDs will be placed opposite the photodiode within a casing that can be clipped to a finger Fig 6 LEDs Probe __Lasing Finger Photodiode Figure 6 Finger Probe Diagram One LED will work at a red wavelength 660nm and the other at a near infrared NIR wavelength 910nm Also in the probe will be a photodetector that will detect the light transm
48. ead Digital Thermometer V911 11 99 Comments Price Quote File Name Yes or No Vendor Accepts Purchase Orders Vendor CVS Pharmacy Address 632 Middle Turnpike Phone Mansfield CT 06268 860 487 2034 Contact Name qd Shipping Total Authorization PURCHASE ORDER REQUISITION UCONN BME SENIOR DESIGN LAB Instructions Students are to fill out boxed areas with white background Each Vendor will require a different purchase requisition Date November 25 2006 Student Name Jenna Sullivan Team Total Expenses Ship to University of Connecticut Lab Admin only Biomedical Engineering FRS U 2247 260 Glenbrook Road Student Initial Budget ERE Storrs CT 06269 2247 Student Current Budget ps Attn Project Sponsor mq Project Name Accessible Home Vital Signs Monitor ONLY ONE COMPANY PER REQUISITION Catalog Description Unit QTY Unit Price Amount E161 11 060 CTS Single Head Pump 1 48 00 48 00 0 00 0 00 0 00 0 00 0 00 0 00 0 00 0 00 0 00 0 00 0 00 0 00 0 00 0 00 Comments Price Quote Shipping 9 18 File Name Total 57 18 Yes or No Vendor Accepts Purchase Orders Vendor Hargraves Advanced Fluidic Solutions Address 127 Speedway Drive Mooresville NC 28117 USA Authorization Phone 704
49. ecial wireless protocol knowledge Assuming that our clients computers are not Bluetooth ready a USB Bluetooth dongle will be purchased usually at 10 20 to provide connectivity on the PC end These USB dongles are easy to use and come with software to install on the PC to allow Bluetooth connectivity Bluetooth communicates data via low power radio waves on the 2 4 GHz frequency This is the ISM frequency band It has been internationally agreed upon to be used only for industrial scientific and medical devices ISM Many devices make use of the ISM band but Bluetooth has precautions in place to prevent interference with these other systems making it and ideal technology for our use One way in which Bluetooth prevents interference is by only sending out very weak signals of about 1 milliwatt This limits Bluetooth s range to about 10m although advances in the technology have made it possible for transmission ranges up to 100m This is an acceptable range considering that our device is meant only for home use However because of this we do advise that users ensure they are within a 10 m radius of their computer when using their vital signs monitor Another way in which Bluetooth limits interference is through frequency hopping This also helps ensure the security of the data being transmitted Bluetooth transmitters use 79 randomly chosen frequencies and hop between them 1 600 times per second Our Bluetooth communications system
50. eight will be monitored by the same system discussed in Design 2 to ensure patient health The scale that will be used is the Homedics SC 200 Digital Scale We plan on taking apart the scale and breaking the connection between the circuit and its digital display From here we will connect the scale s circuit to one of our output displays The scale will already have been calibrated and tested by its manufacturer We will do additional testing by comparing known weight values dumbbells to the values displayed by the scale when we place the weights on it 2 1 3 7 Secure E mail System In the first two designs we sent the vital signs data through a secure website Another viable option that we explore in this design is a secure e mail system This can be accomplished through certifiedmail com This website provides the software necessary to protect e mail using transparent encryption It provides easy to use software that the recipient of the e mail does not need to download in order for complete security to occur For starters there is no password required and information is automatically secured every time with the Certified Mail software It is also possible to track the e mail to determine that the e mail was received and who opened it A time download and 10 per month provides these features 2 1 3 8 Power Supply The power supply of this design is the same as that of Designs 1 and 2 The device will mainly be run from an external power source
51. ember 25 2006 Student Name Michael Kapinos Team Total Expenses 2 000 Ship to University of Connecticut Biomedical Engineering U 2247 260 Glenbrook Road Storrs CT 06269 2247 Project Name Accessible Home Vital Signs Monitor Lab Admin only FRS Student Initial Budget Student Current Budget Project Sponsor ONLY ONE COMPANY PER REQUISITION Catalog Description Unit QTY Unit Price EG 000138 AC to DC Power Converter 1 29 95 Comments Price Quote File Name Yes or No Vendor Accepts Purchase Orders Vendor Shop com Address www shop com Phone 1 866 746 7005 Contact Name 72 Shipping Total Authorization PURCHASE ORDER REQUISITION UCONN BME SENIOR DESIGN Instructions Students are to fill out boxed areas with white background LAB Each Vendor will require a different purchase requisition Date November 25 2006 Student Name Michael Kapinos Team Total Expenses Ship to University of Connecticut Biomedical Engineering U 2247 260 Glenbrook Road Storrs CT 06269 2247 Attn Project Name Accessible Home Vital Signs Monitor Lab Admin only FRS Student Initial Budget Student Current Budget Project Sponsor ONLY ONE COMPANY PER REQUISITION Catalog Description Unit Amount
52. es the optical properties of blood to determine oxygen saturation Blood oxygen saturation SpO is defined as the ratio of oxyhemoglobin HbO to the total concentration of hemoglobin in the blood Hb HbO HbO Spo P THb HbO This can be determined by measuring the difference in the light absorption spectra of oxyhemoglobin and deoxyhemoglobin 16 Assuming that the transmission of light through the arterial bed in the finger is only influenced by the concentrations of Hb and HbO and their absorption coefficients at two measurement wavelengths red and near infrared then the light intensity will follow the Beer Lambert Law Thus for an artery of length Z through which light of intensity In passes I 1 10 ot at wavelength 21 and I 51 10 2 at wavelength Az where I and L are the intensities of the light passing through the artery at each wavelength Cois the concentration of HbO Cris the concentration of Hb a is the absorption coefficient of HbO2 at wavelength A and Qm is the absorption coefficient of R DEEITARS Lc e I then blood oxygen saturation can be calculated from C a R a S O o r2 rl P C C a TAn R x G a o r 29 Circuit Design The block diagram of the pulse oximeter below shows an overview of the circuits that are involved and will be included in the vital signs monitoring device Fig 14 Sample and Bandpass filter Amplifier hold circui
53. este FA To Oo Roa E Sap TM deerat rhe 55 57 AS alley O 57 58 5 Impacts of Engineering Solutions 0 cece cece cence ence eee ne eee emen 58 60 6 Late Dong Learning 2e uere ttr eeu bebe welds etate eH da tbt d eodera bbb d d 60 61 T Budgetand Timelines aree Las Pen vot redd Ac ct etr edd e iU 62 64 La Budget c aspetto oae o eo ae ec Masc b ed dece an iesus e 62 T2 Witte WING isi cir A M ROC D Sessa ER Tb uc ett 63 64 8 Team Members Contributions to the Project 65 66 COI O TL TI UU IU 66 A nude bee noiahesee PR SERO ys CREME EEER PARAR C REM 67 68 Ide Acknowledements us ei eio ri Hoe tiae it sa etel Ry LN IER 68 VA Ap Pennies stati len winnaar tarda vested etc exeo bad duce edu despide s 68 81 12 1 Updated Specifications cessio een AR rox CR Ex EX KEY ERN ECT eRUS 68 70 12 2 Purchase Requisitions and Quotes esee 71 81 Figures and Tables 1 Welch Allyn Vital Signs Monitor 300 Series ccc cee cc ence eee e cence eee enee ene es 6 2 DRE Philips SureSigns VS1 Vital Sign Momitor 00 cceceeeeceee eee eneeeeeeeeeees 7 3 Thermistor Linearizing Circuit Destinia 12 4 Block Diagram of Automatic Blood Pressure Design 2 sseessesssss 15 5 Pulse Oximeter Circuit Block Diagtafh old Ete rA QUERER UTR NINE ricino 19 6 Finger Probe Diagram Design 3 cote de p A 19 7 Pulse Oximeter Circuit DIAPEAI cdta tasar RS 20 8 Image of Thermocouple Nose Clip Design 3 ccc
54. ever the thickness of the patient s skin tissue etc 16 Calibration of the pulse oximeter will be done through the lookup table stored on the microprocessor Because we are using a Datascope compatible probe we will obtain and load Datascope s lookup table onto our microprocessor The pulse oximeter will be tested through a pulse oximeter simulator a device designed to test the accuracy of pulse oximeters We plan to find a simulator to use at a local hospital or the UConn Health Center 13 Heart Rate Pulse oximetry will also be used to determine heart rate as in Design 1 There are pulsatile signals detected in the intensity of the detected light by the photodiode One pulse is one cardiac cycle The microprocessor will count the pulses to determine heart rate beats per minute which will be displayed on an LCD screen 2 1 2 4 Non Invasive Blood Pressure In this design we will incorporate our own automated non invasive blood pressure cuff into the system Blood pressure will be automatically measured through the oscillometric method 15 This is done by wrapping a blood pressure cuff around the upper arm and inflating it until the pressure around the arm due to the cuff collapses or occludes the brachial artery The cuff is then slowly deflated As the cuff deflates blood starts pumping through the brachial artery causing minute vibrations of 5 to 1 mmHg in the cuff 4 The pressure at which these vibrations start is the systol
55. gns monitor that will measure 6 different vital signs Our last design only measured 4 vital signs heart rate blood oxygen saturation blood pressure and temperature but this design adds the equipment to measure weight and respiratory rate The thermometer linearizing circuit has been changed from a resistor to a Wheatstone bridge which is more common in medical instrumentation and reduces heat created by the circuit itself Instead of purchasing an automated noninvasive blood pressure monitor and incorporating it into our device this report includes a design for an automated blood pressure system that will be part of the system itself Finally in this design we are using a Blackfin microprocessor instead of a PIC 16F877 The Blackfin was chosen for its superior processing capabilities and its ability to be programmed through LabVIEWTM 2 1 2 2 Thermometer As with Design 1 a thermistor circuit will be used to measure body temperature The thermistor will be in the form of a commercially purchased oral temperature probe The probe we have chosen for this is the Welch Allyn 02893 000 Sure Temp 690 Oral Probe from DREMed com for a cost of 74 00 before shipping and tax Unlike our first design where the thermistor was linearized by a resistor the thermistor will be linearized through the use of a Wheatstone bridge THERMIS TOR RTI v1 Wo 41 42 Differential Amp Figure 3 Thermistor Linearizing Circuit For our use as an
56. he wall into the D C power supply we need to power the device From there we will still have too much voltage and our machine will burn out To bring down the voltage levels the best possible way is to use linear voltage regulator Fig 38 The regulator we have decided to use is the AIC1086 It is a low drop regulator with 1 5A current output capability This regulator will take in voltage from the power source and output a predetermined voltage of 2 85V 3 3V or 5V Before and after the linear voltage regulator capacitors 47 are needed to act as a filter None of our transducers should require more than 5 volts These regulators are also very inexpensive at only around a couple of dollars each Linear Voltage Regulator V1 Pushbutton C2 CAPACITOR C1 CAPACITOR Figure 38 Voltage Regulator Circuit 2 2 2 12 USB Device The USB device is a very important part to include in this project The main job of the USB device is to store the readings taken by the vital signs monitor This device will then be connected to a computer in which it is possible to send the readings to any computer that has an Internet connection The USB device that we have decided to use is the Philips PDIUSBD12 The price of this device is only around 4 00 The PDIUSBD12 is a chip that will connect the microcontroller to the USB port This device uses parallel technology to connect to the microcontroller For the rest of the project a Blackfin will be u
57. hen be snapped into the whole Once the button is snapped into the hole it has wings that will then open causing the button to not be removed The only visible problem with this product is that the button may be too small The buttons seem to cost around 10 but could be more depending on if the customization of the buttons raises the price Connecting either choice of button to our main circuit does not really require a lot of work Our buttons are basically going to act like a switch either turning the power on or off The start button will be connected to the beginning of the circuit There will be a switch in the circuit that will either be open if the circuit is not working or closed if power is to be given to the entire circuit When the start button is pressed the switch on the circuit will close allowing for the power supply to be sent to and power the rest of the circuit When the patient feels the process is complete they will be able to press the stop button which will allow for the circuit to open disallowing any power to get through to the circuit The button is a two probe button One probe will be attached to the circuit by a switch and the other probe will be attached to the ground 2 2 2 15 Casing In order to safely enclose the internal circuitry of our design a plastic enclosure needs to be manufactured We will use the company Toolless Plastic Solutions to manufacture our casing In order for this company to manufacture our case w
58. ic pressure and the pressure at which they stop is the diastolic pressure 5 The block diagram in Fig 4 illustrates how this method will be used to measure blood pressure in the accessible vital signs monitoring system Each system in the flow chart is described in more detail in the following paragraphs When the blood pressure Start button on the vital signs monitor is pressed the blood pressure cuff will be inflated to about 40mmHg above normal 160mmHg The blood pressure cuff used will be a DRE Adult single lumen cuff from DREMed com at a cost of 37 00 before shipping and tax The cuff will be inflated by a Sensidyne AA Series Micro Air Pump A microprocessor second to the microprocessor controlling the rest of the device will control the inflation of the cuff The sensor used to sense cuff pressure will be the NPC 1210 low pressure sensor from GE Once the pressure sensor determines that the cuff has been inflated to 160mmHg the cuff will deflate slowly at a rate of 2 3mmHg sec Deflation will occur through a release valve brand to be determined As blood begins flowing through the brachial artery again it will cause small pulsations that will be picked up by the pressure sensor in the cuff This waveform will be analyzed by the microprocessor to determine the systolic and diastolic pressures A threshold voltage level will be set This will be done by experimentally comparing blood pressure readings from a sphygmometer or othe
59. ice are the accessibility constraints that it needs to meet Our device was designed to be properly accessible so that it will be of use to our clients and meet their needs Audio and visual output along with Braille and raised universal symbols were used to make the device user friendly to anyone with vision or hearing impairment Also the simple user interface of the device allows it to be used by individuals of all ages and technological savvy This leads into sustainability Our device was designed with its ability for future and continued use in mind Not only must the device be designed so that it can last and function properly for years but it also needs to use up to date parts and technology so that it does not become outmoded An example of this was the selection of the rechargeable battery for our device In many vital signs monitors being used rechargeable lead batteries power the device However lead materials are currently being phased out of medical devices so we chose to use a nickel cadmium rechargeable battery in our design This is one step that was taken to ensure that our device will still be acceptable for use years from now Because this is a medical device and will have direct contact with our clients client patient safety was an important constraint in our design process All circuits and power sources must be properly grounded to prevent accidental electrocution and safety measures had to be put in place to prevent an injury
60. igns fall out of range a signal from the microcontroller will be sent to the SpeakJet and alarm light The alarm lights will be tested by checking what the manufacturer recommended voltage to run them at is and then confirming that experimentally Test values will be sent to the microprocessor to confirm the activation of the alarm over the programmed range These values will be acquired by applying the known voltage for them to the microprocessor I O pin that would normally receive them For example if we know that a voltage of 6V from the thermometer circuit is equivalent to a body temperature of 92 F and that value is in our alarm range we will apply 6V to the thermometer I O pin of the microprocessor to see if the alarm activates as it should 46 http img alibaba com photo 50538513 Alarm Lights Warning Lights jpg Figure 37 Alarm Light 2 2 2 10 Secure Website After the patient s vital signs have been gathered and recorded they need to be sent to their primary healthcare provider To maximize patient privacy we have devised a way to securely transmit the patients health information minimizing the risk of interception We will create an encrypted password protected website to which the patient uploads the information from their USB stick To ensure that the website is secure HTML encryption software will be used to encrypt the contents of the website allowing only those with the correct username and password to access it W
61. int in our device design The internet provides rapid transfer of information but it is filled with predators and opportunists who like to access the private information of others It is important for us to protect our clients when they are contacting their physicians so that their medical information does not end up all over the World Wide Web By paying heed to these constraints and working with them not around them our accessible home vital signs monitoring system has been designed with the best interests of our clients and society at heart This ensures that we have designed an economically 56 feasible device affordable for our clients Our device is appropriately designed for the environment which it will be used in and with careful part selection it will sustain and continue to be appropriate for the home monitoring of vital signs 4 Safety Issues Safety plays a crucial role when designing a product especially one that contains electrical components Because our design will be comprised mainly of electrical components we have strived to effectively enclose the inner circuitry of our final design with a durable non conductive completely closed casing The casing of our final design will show no wires circuit boards or any part of the inner circuitry Loose wires have the potential to not only cause the device to operate ineffectively but they could also be hazardous to the patient Any moisture from the air or water accidentally s
62. ions explained previously are good for theory but not for practice As such pulse oximeters are usually calibrated by comparing the oximeter R value SpO ratio to the oxygen saturation ratio obtained from in vivo samples using human test subjects Manufacturers of pulse oximeters do this and determine calibration curves or lookup tables for their devices The pulse oximeter will be calibrated tested through a pulse oximeter simulator a device designed to test the accuracy of pulse oximeters We plan to find a simulator to use at a local hospital or the UConn Health Center 34 Heart Rate Pulse oximetry will also be used to determine heart rate There are pulsatile signals detected in the intensity of the detected light by the photodiode Fig 22 14 03 38 2 14 03 43 2 20 02 23 7 20 02 28 7 Figure 22 Pulsatile Signals Found in the Intensity of Detected Light 16 One pulse is one cardiac cycle The microprocessor will count the pulses to determine heart rate beats per minute which will be displayed on an LCD screen The microprocessor will be programmed calibrated to count the peaks of the signal for 10 seconds Multiplying this by 6 will give the heart rate in beats per minute This function will be tested by comparing the heart rate given by the pulse oximeter to that of a group member taken manually 2 2 2 3 Non Invasive Blood Pressure Blood pressure will be automatically measured through the oscillometric method 15
63. itted through the finger The complete schematic Fig 7 of the pulse oximeter shows how each of the different circuits previously described in Designs 1 and 2 will be integrated into a whole 19 Figure 7 Pulse Oximeter Circuit Diagram Calibration of the pulse oximeter will be done through the lookup table stored on the microprocessor Manufacturers of pulse oximeters determine calibration curves or lookup tables for their devices The pulse oximeter will be calibrated tested through a pulse oximeter simulator a device designed to test the accuracy of pulse oximeters We plan to find a simulator to use at a local hospital or the UConn Health Center Heart Rate Pulse oximetry will also be used to determine heart rate There are pulsatile signals detected in the intensity of the detected light by the photodiode One pulse is one cardiac cycle The microprocessor will count the pulses to determine heart rate beats per minute which will be displayed on an LCD screen This function will be tested by comparing the heart rate given by the pulse oximeter to that of a group member taken manually 20 2 1 3 4 Non Invasive Blood Pressure As in Design 2 blood pressure will be automatically measured through the oscillometric method 15 The blood pressure cuff used will be a DRE Adult single lumen cuff from DREMed com at a cost of 37 00 before shipping and tax The cuff will be inflated by a Sensidyne AA Series Micro Air Pump A microprocess
64. ization 74 PURCHASE ORDER REQUISITION UCONN BME SENIOR DESIGN LAB Instructions Students are to fill out boxed areas with white background Each Vendor will require a different purchase requisition Date November 25 2006 Team amp Student Name Michael Kapinos Total Expenses Ship to University of Connecticut Lab Admin only Biomedical Engineering FRS pee U 2247 260 Glenbrook Road Student Initial Budget mm Storrs CT 06269 2247 Student Current Budget om Attn Project Sponsor ERI Project Name Accessible Home Vital Signs Monitor ONLY ONE COMPANY PER R EQUISITION Catalog Description Unit Amount 693 1241 6634 1121 PIC Microprocessor 5 84 0 00 0 00 0 00 0 00 0 00 0 00 Comments Price Quote Shipping 0 00 File Name Total 5 84 Yes or No Vendor Accepts Purchase Orders Vendor Microchip Direct Address www microchipdirect com Authorization Phone Contact Name 75 PURCHASE ORDER REQUISITION UCONN BME SENIOR DESIGN LAB Instructions Students are to fill out boxed areas with white background Each Vendor will require a different Date purchase requisition November 25 2006 Student Name Michael Kapinos Team Total Expenses 2 000 Ship to University of Connecticut Biomedical Engineering U 2247 260 Glenbrook Road Storrs CT 06269 2247
65. kfin BF535 Processor 1 23 63 23 63 0 00 0 00 0 00 0 00 0 00 0 00 0 00 0 00 0 00 0 00 0 00 0 00 0 00 0 00 Comments Price Quote File Name Yes or No Vendor Accepts Purchase Orders Vendor Crystalfontz Address Phone www analog com 1 800 262 5643 Contact Name 81 Shipping Total 23 63 Authorization 82
66. ll supply 50us pulses to the LEDs at a rate of 1 kHz Finally an n channel enhancement mode MOSFET connected across the each LED is used to pulse the output from them In the receiving end of the circuit is the photodetector The photodiode detects the light transmitted through the finger as current 16 The current is converted to voltage by an op amp configured for current to voltage conversion Because the LED light is pulsed sample and hold circuits are needed to reconstitute the waveforms at each of the two wavelengths The timing circuits that were used to control the red and NIR LED drivers also are used to provide the control pulses for their corresponding sample and hold circuits 16 A simple sample and hold circuit can be created from a FET switch capacitor and op amp Once the signal goes through the sample and hold circuit it is sent through a band pass filter with cutoff frequencies 5Hz and 5Hz to eliminate high frequency noise and the d c offset Then it is amplified and sent through an A D converter and the microprocessor to be analyzed A lookup table stored in the microprocessor will be used to calculate SpO values This signal is also sent through a low pass filter to extract the d c value of the transmitted signal which is then sent to an automatic gain control circuit the same as in Design 1 The gain control circuit adjusts the light intensity from the LEDs so that the d c level always remains at the same value what
67. lse oximeter Q1day Mon 2 12 0 Mon 2 12 07 16 19 3 Add LCD screens to Blackfin circuit 5days Fri 2 2 07 Thu 2 8 07 20 E Set up pump valve assembly for BP circuit 0 5 days Wed2 14 0 Wed 2 14 0 21 3 Test valve pump assembly 05 days Wed2 14 0 Wed2 14 0 20 22 E Build blood pressure circuit 1 day Fri 2 16 01 Fri 2 16 07 23 E Test blood pressure circuit 2days Mon2 19 0 Tue 2 20 0 22 24 E Test BP inflation control circuit kill s witch 2day Wed2 21 0 Thu 2 22 0 23 25 E Experimental determine sys and dias thres hold voltages Q1day Wed2 21 0 Wed2 21 0 22 26 E Build respiratory rate probe 0 3 days Fri 2 23 01 Fri 2 23 07 27 E Build respiratory rate circuit 0 3 days Fri 2 23 01 Fri 2 23 07 28 E Test respiratory rate circuit 0 3 days Fri 2 23 05 Fri 2 23 01 26 27 29 E Determine scale LCD screen connections 1 day Fri 1 19 05 Fri 1 19 07 30 E Connectscale LCD output to Blackfin 1day Fri 1 26 0 Fri 1 26 07 29 31 3 Test speech module 5days Fri 2 16 01 Thu 2 22 0 32 3 Program speech module 3days Fri 2 23 01 Tue 2 27 0 31 33 E Connectspeech module to Blackfin 2days Wed 2 28 0 Thu 3 1 07 31 32 34 E Add speaker to device 1 day Fri 3 2 05 Fri 3 2 01 35 E Test speaker with speech module and Blackfin 1day Mon 3 12 0 Mon 3 12 0 34 36 E Build USB module 5days Mon 1 29 0 Fri 2 2 01 37 E Calibrate and Troubles hoot USB module 3 days Mon 2 5 07 Wed 2 7 01 36 38 E TestUSB Module 1day Fri 2 9 05 Fri 2 9 07 39 ConnectUSB Module to Blackfin 3days Mon 2 12
68. measurement and a printer for record keeping This device also comes with an optional wheeled stand making for easy transportation The Welch Allyn system has an alarm that will go off if patients forget to take their vital signs at the specified time With all of the above features the Welch Allyn Monitoring system is approximately 3000 The Philips SureSigns VS1 Vital Sign Monitor includes non invasive blood pressure NIBP and pulse rate measurement systems It weighs 8 pounds and is 9 3 inches tall 9 4 inches wide and 9 8 inches deep Fig 2 It can store up to 400 sets of vital signs and has a battery life of 6 hours A bright LCD display displays the latest vital signs readings and a backlit screen displays historical trend information With these features and to monitor only two vital signs this device costs approximately 2000 Figure 2 DRE Philips SureSigns VS1 Vital Sign Monitor Both the Philips and Welch Allyn monitors lack audio output and obvious buttons Though both have internal memory neither have the option to save vital signs off of the monitor 1 3 2 Patent Search Results There are many different types of vital signs monitors so many patents of vital signs monitors exist One such patent is a blood pressure and heart rate monitoring method and apparatus by Hewitt U S patent number 4 967 756 This system uses an auscultatory transducer and a microprocessor based circuit to record blood pressure and heart rate It al
69. n the site content gets modified and needs re uploading In order to use this encryption software a website using the UCONN Biomedical Engineering server will be created 2 1 2 9 Power Supply The power supply of this design is the same as that of Design 1 The device will mainly be run from an external power source by using a power cord It will also be equipped with rechargeable backup batteries in case of a power failure For the power supply we plan on using a very generic universal power cord which will plug into the back of our device and then also plug into the wall For the backup power supply we 17 determined the best way would be to use nickel cadmium rechargeable batteries The need for a backup battery is so the patient can take signs even if the power is gone 2 1 3 Design 3 2 1 3 1 Objective As we continued to update and revise our design parts of the design changed In our last two designs we purchased a pulse oximeter probe to incorporate into our vital signs monitor To save money we created a design for a pulse oximeter probe that we will build The respiratory belt used in the last design to measure respiratory rate has been replaced by a thermocouple a more cost effective and accurate solution Bluetooth wireless communication has been used in this design to transmit collected vital signs from the monitor to the client s computer This removes the USB flashdrive and the need to physically transport vital signs data to
70. nces 1 Al Nashash Hasan Electrical Safety of Medical Equipment University of Sharjah School of Engineering lt http www ewh ieee org r8 uae Elect Safety Med Equip pdf gt 2 Basic Statistics About Home Health Care National Association for Home Care amp Hospice 2004 lt http www nahc org 04HC_Stats pdf gt 3 Blackfin Embedded Processor ADSP BF535 Analog Devices 2006 lt http www analog com UploadedFiles Data_Sheets ADSP BF535 pdf gt 4 Blood Pressure Monitor lt http www circuitcellar com fi2003 abstracts F190abstract pdf gt 5 Chua C S and Siew Mun Hin Digital Blood Pressure Meter Freescale Semiconductor May 2005 lt http www freescale com files sensors doc app_note AN1571 pdf gt 6 DeMarre Dean A and David Michaels Bioelectronic Measurements New Jersey Prentice Hall Inc 1983 7 Design and Engineering Toolless Plastic Solutions 2006 lt http www toolless com gt 8 Getting Started with Blackfin Processors Analog Devices 2006 lt http www analog com gt 9 Lineared NTC Thermistor eCircuit Center 2002 lt http www ecircuitcenter com Circuits therm_ckt1 therm_ckt1 htm gt 10 Northrop Robert B Noninvasive Instrumentation and Measurements in Medical Diagnosis New York CRC Press 2002 11 Northrop Robert B Class notes BME 255 University of Connecticut Oct 17 2006 12 Number of c
71. ng In order for this company to manufacture our case we need to submit an AutoCad drawing of the final casing design Since we will not know the exact size and placement of all 6 holes for the LCD screens and the various I O ports in the casing the design will be submitted in the spring semester when all the parts have been ordered and more about the final design is known Toolless Plastic Solutions requires no tooling or molds and therefore will be a cost effective way to obtain an enclosure for our design 7 The company uses CNC Computer Numerical Control machining and fabrication process to build plastic casings We will not know the exact price of the casing until a design is sent for a quote 2 1 3 12 Processing Display and Alarm As in Design 2 the processor we are going to use for this design is the Blackfin ADSP BF535P Digital Signal Processor by Analog Devices Like the PIC 23 microcontrollers the Blackfin contains an internal analog to digital converter We will use the PF pins I O ports on microcontrollers on the Blackfin to function as inputs for the transducers and outputs for the LCD screens and speaker Due to the Blackfin s abilities it should be the only microprocessor we need for our device The Blackfin can take C C code as well as LabVIEW Vi s After the data has been processed the information will be sent to 4 different areas the LCD displays the speech module the speaker and alarm For the LCD displays
72. nts specific needs This device will improve our clients quality of life by allowing health care professionals to monitor them from home rather than from a bed in a hospital or nursing home Our clients want to maintain their health not appear sick to their friends and continue to live with their families The device we design will allow them to do these things It will be accessible to the vision and hearing impaired and it will be cost effective Most systems available today are very expensive and our purpose is to make an affordable device that is also accessible and easy to use 1 3 Previous Work Done by Others 1 3 1 Products Previous work on home vital signs monitors can be seen in the current models that are in hospitals and homes There are many different types and brands of vital signs monitors available today They range in size function and price Most are very expensive costing patients or healthcare providers upwards of 2 500 per system Below are the descriptions of a few select monitors The monitor shown below Fig 1 is the Welch Allyn Vital Signs Monitor Figure 1 Welch Allyn Vital Signs Monitor 300 Series This device is small and lightweight It is 6 6 inches tall 10 inches wide has a depth of 6 inches and weighs 5 4 pounds Some of its features include an easy to read LCD screen blood pressure monitor built in memory for up to 99 sets of measurement data thermometer pulse measurement blood oxygen level
73. olesalepoint com We will to build handles onto the scale to offer better support and safety to our clients with mobility problems To connect the scale to our device we will take apart the scale and break the connection between the circuit and its digital display Then we will connect the scale output to our microprocessor to be saved and sent to an LCD screen The scale will already have been calibrated and tested by its manufacturer We will do additional testing by comparing known weight values dumbbells to the values displayed by the scale when we place the weights on it 2 1 2 7 Processing Display and Alarm In this design the microprocessor we have chosen to use is the Blackfin ADSP BF535P Digital Signal Processor by Analog Devices This processor is extremely versatile due to the fact that it can function as both a microcontroller and a DSP Digital Signal Processor allowing for either 100 DSP 100 microcontroller or a combination of the two 8 This makes the Blackfin ideal for our design due to the fact that we are going to input and output the data like a microcontroller but use the digital signal processing features to analyze and filter the signals FIR and IIR filters Like the PIC microcontrollers the Blackfin contains an internal analog to digital converter Using DSP one can more easily design and modify their work due to the fact that it is all computer based DSPs are also much faster than microcontrollers A typical P
74. one cohesive work Throughout the semester Jenna focused on group communication and timeliness in completing work And Jenna did research into client needs and the home health care environment 9 Conclusion As healthcare moves out of the hospital and into the home reliable technology for monitoring patients health is needed Vital signs monitors provide basic yet important information about a patient s physical well being Unfortunately many of the vital signs monitoring systems available today are very expensive and inaccessible Most are designed for hospital use and have complicated interfaces that do not blend well with the home environment More devices are needed that are designed specifically for home use by patients their families and caregivers The accessible home vital signs monitoring system described in this report fulfills the need for an accessible user friendly home use vital signs monitor The simple 3 button design makes the device easy to use for all ages and abilities To provide comprehensive health care monitoring our device is designed to record the following six 6 vital signs body temperature blood oxygen saturation heart rate blood pressure weight and respiratory rate Accessibility is addressed through the speech module auditory and visual alarms large LCD screens and buttons customized with Braille or Universal Symbols These features allow us to meet the needs of our clients with a device that is acces
75. or second to the microprocessor controlling the rest of the device will control the inflation of the cuff The sensor used to sense cuff pressure will be the NPC 1210 low pressure sensor from GE Once the pressure sensor determines that the cuff has been inflated to 160mmHg the cuff will deflate slowly at a rate of 2 3mmHg sec Deflation will occur through a release valve brand to be determined As blood begins flowing through the brachial artery again it will cause small pulsations that will be picked up by the pressure sensor in the cuff This waveform will be analyzed by the microprocessor to determine the systolic and diastolic pressures This process is exactly the same as describe in Design 2 Due to the safety issues that arise with automatic blood pressure systems we have incorporated a kill switch into our design Fig 17 18 If at any time during the blood pressure measurement the user wants to stop the inflation of the cuff and rapidly deflate it they just need to press the vital signs monitor On Off button This will cut power to the whole device and open the pressure release valve This method bypasses the microprocessor avoiding any software bugs that an emergency stop button might encounter As stated in Design 2 the automated blood pressure system will be calibrated experimentally This will be done through establishing a threshold voltage by which correct pressure measurements for systolic and diastolic pressures can
76. or starting a fire In addition to the electrical safety issues it was also made sure that the operator of the monitor does no harm to the patient while taking measurements Each instrument used to obtain measurements was carefully chosen to be as simple and safe as possible Out of the four vital signs being obtained the only one which requires any skill to operate is blood pressure Using the blood pressure cuff incorrectly could not only cause the monitor to record the wrong vital signs but also harm the patient Squeezing the blood pressure cuff too tightly could injure the patient To minimize this potential hazard we will use an automatic blood pressure cuff allowing the person who is taking the readings to have no prior skill Since the people taking the vital sign readings may be elderly young or physically impaired the automatic blood pressure cuff makes gathering data relatively simple Even though the automatic blood pressure cuff is simple to use it is still not completely foolproof 5 Impact of Engineering Solutions Much of the technology used in our design for an accessible home vital signs monitoring system is not new but the manner in which it is being employed is valuable There are few if any accessible vital sign monitors currently available Patent and web searches have not revealed devices on the market comparable in that regard to the device that we have designed The design of an accessible vital signs monitor will imp
77. ore suitable code to program the processor When designing a product with Blackfin many helpful tools are provided to the engineer to aide in the design which has already been purchased by the Biomedical Engineering department These include simulation software an evaluation board and an emulator Before the processor is even programmed VisualDSP software will be used to simulate the behavior of the DSP chip Using this software we will be able to build edit and debug our DSP program before we even have the actual processor which is done solely on the computer After the simulation is complete evaluation of the simulation is performed using the EZ KIT Lite evaluation system to determine the specific Blackfin processor that fits our needs This board Fig 31 41 connects up to the computer via a cable allowing us to run our simulation program After the evaluation process the JTAG emulation board Fig 32 will be used to serially scan the I O status of each pin on the device as well as control internal operations of the device This hardware connects our PC to the actual process target board via a USB cable Table 1 Blackfin Specifications Blackfin Specifications Clock Speed MHz 350MHz MMACS MAX 700 RAM Memory Kbytes 308 External Memory Bus 32bit Parallel Periph Interface No PCI Yes USB Device Yes UARTS Timers Yes Watchdog Timer RTC Yes Core Voltage V 1 0 1 6 Core Volt
78. ound implies 15 To measure blood pressure an automated system will be used that measures Korotkoff sounds Due to the complexity of the automated system a commercially available system such as the Omcron Automatic Blood Pressure Monitor will be purchased and integrated in our vital signs monitor The resulting measurement for blood pressure will be displayed on an LCD screen on the front of the vital signs monitor 2 1 1 5 Processing Display and Alarm To process the data we will use the Microchip PIC16877F microprocessor After the data has been processed the information will be sent to 4 different areas the LCD displays the speech module the speaker and alarm For the LCD displays 4 displays from Crystal Fontz will be used Each display measures 80mm x 36mm with a viewing area of 66mm x 16mm and a character height of 6 56mm 10 To produce the speech we will use the Magnevation SpeakJet IC It is an 18 pin IC that uses a mathematical sound algorithm to control an internal five channel sound synthesizer to produce sound The SpeakJet can be controlled by a single I O line from our PIC16877F Microcontroller 13 Since this microchip requires phonetics and not text the TTS256 Text to Code IC will have to be used in conjunction with the SpeakJet The TTS256 is an 8 bit microprocessor programmed with letter to sound rules This built in algorithm allows for the automatic real time translation of English ASCII characters into allophone
79. pilled near the device could cause a spark and start a small fire It is for this reason that it will be recommended that all liquids be kept off of and way from the monitor regardless of how good the casing Also it is important for the casing to be made of a non conductive material such as plastic so that if the hot side of the power system touches the side of a casing there is no danger to the user of the monitor The inner part of the monitor should be designed so that neither the hot or neutral part of the power cord touches the casing If the casing were conductive and the hot wire touches the side of the case then the case would be made electrically common to the wire and touching the case would be just as hazardous as touching the bare wire In addition it is always important for an electrical design to have a solid connection to earth ground A power system with no secure connection to earth ground could pose a safety hazard There is no way to guarantee how much or how little voltage will exist between any point in the circuit and earth ground By grounding one side of the power system s voltage source at least one point in the circuit can be assured to present no shock hazard One way to ensure proper ground is to use a three prong plug The third prong on the power cord provides a direct electrical connection from the appliance case to earth ground making the two points electrically common with each other If they
80. piratory Rate In this second design we have incorporated the measurement of respiratory rate To do this the MLT1132 Piezo Respiratory Belt Transducer from AD Instruments will be used Using a piezoelectric sensor placed between two strips this belt measures the changes in thoracic or abdominal circumference due to respiration inhalation and exhalation By stretching the elastic due to respiration strain is placed on the sensor which generates a voltage This voltage is then sent through the transducer and converted into digital signals to be processed by the Blackfin In plotting the voltage sent from the transducer we can count each breath as a peak on the graph which corresponds to the maximum distance the belt traveled for that breath To test the accuracy of this transducer we will compare our results obtained from using this respiratory belt to the results obtained the BioPac software Calibrating the respiratory belt can be done by knowing the voltage of the piezoelectric sensors at rest Ideally there should zero voltage because there is no stress on the sensors If the sensors do exhibit some voltage the device will be zeroed at that corresponding voltage reading 2 1 2 6 Weight Measuring patient weight has also been included in this second design This will be done by purchasing a commercially available digital scale and incorporating it into our device The scale that will be used is the Homedics SC 200 Digital Scale 24 95 at wh
81. pressures and does so often Nevertheless we expect to see some slight differences in the measurements from our device and the sphygmometer because of the inherent degree of imprecision in manual blood pressure measurement This is why it is important to have a professional operating the sphygmometer Their experience with the device and the art of blood pressure measurement should reduce the likelihood of human error Finally the rapid cuff deflation will be tested by experimentation turning the vital signs monitor off during use 2 2 2 4 Respiratory Rate Respiratory rate will be measured using a thermocouple The thermocouple will be clipped to the client s nose and will measure the change in temperature caused by inspiration and expiration Fig 27 The thermocouple will convert the changes in temperature it detects to changes in voltage Through experimentation voltages thresholds will be set to define the changes in temperature that correspond to inspiration and expiration By counting the number of inspiration and expiration pairs that occur in a given period of time we can determine respiratory rate Figure 27 Image of Thermocouple Nose Clip The circuit for the thermocouple will be powered by the battery The voltage from the thermocouple will be linear over our range approx 65 F to 98 F so the signal from the thermocouple only needs to be filtered and amplified resister and capacitor values to be determined before being A D
82. r commercial device to those detected by our pressure sensor Once 4 pulsations peak above the threshold level the voltage will be recorded and from that value the systolic pressure determined The microprocessor will continue to monitor the blood pressure readings and diastolic pressure will be taken when the voltage drops below the threshold voltage for 2 pulsations After the diastolic pressure is determined a command from the microprocessor will deflate the cuff quickly and completely 14 Figure 4 Block Diagram of Automatic Blood Pressure Measuring System Due to the safety issues that arise with automatic blood pressure systems we have incorporated a kill switch into our design Fig 16 18 If at any time during the blood pressure measurement the user wants to stop the inflation of the cuff and rapidly deflate it they just need to press the vital signs monitor On Off button This will cut power to the whole device and open the pressure release valve As stated previously the automated blood pressure system will be calibrated experimentally This will be done through establishing a threshold voltage by which correct pressure measurements for systolic and diastolic pressures can be made Final testing of the device will be done by comparing its blood pressure readings to those of a sphygmometer Finally the rapid cuff deflation will be tested by experimentation turning the vital signs monitor off during use 15 2 1 2 5 Res
83. ransmission 2 1 3 10 Pushbuttons An important feature of our design is the buttons involved We will include buttons with a Universal Symbol or Braille so individuals with vision impairment can use them A company that offers customizable buttons is Grayhill The model button from Grayhill that fits our project is a rectangular button that is about 15 by 20 millimeters These buttons are very easy to secure The buttons require a proper size whole to be drilled in the area where the buttons will be placed The buttons will then be snapped into the hole Once the button is snapped into the hole it has wings which will open to secure it The only visible problem with this product is that the button may be too small and also that we are not yet aware of the price We are awaiting a price quote from the Gray Hill Company The buttons will act like a switch either turning the power on or off The start button will be connected to the beginning of the circuit There will be a switch in the circuit that will either be open if the device is off or closed if power is to be given to the entire circuit When the start button is pressed the switch on the circuit will close allowing for the power supply to be sent to and power the rest of the circuit 2 1 3 11 Casing In order to safely enclose the internal circuitry of our design a plastic enclosure needs to be manufactured We will use the company Toolless Plastic Solutions to manufacture our casi
84. rmocouple Nose Clip Optimal Design oooooccccccncccnconccnncnnacos 39 28 Circuit for Respiratory Rae ar oo a rues coda vester ORI URER OR dedu Febr ads 40 29 Homedics SC 200 Digital Scale ooooroncoccconcncacoronononconcroncnc nro nononenno nos 40 30 Blackin HAE A A aes uUo aa Ep SU na IM UD CEU UN E OLI 42 31 BZ KitLine Byaluation Bodtd i ce e I o erbe EOD DE 42 LITA A O as CUT oS oS woah ate 43 39 A e veo lo PE tab e ev Ea dues 44 A PHP HEP 45 35 Pin Diagrariof TITS ir raa tieu decas ban EV ee ER UV UE ddaltecg au ud 45 36 Small Speaker for Audio Output cepi eeNu Eo Oe ATE IR TA EA E HAT ERE ares 46 AT oA Ta BOL 322r os denne o vx edad otio cual Cr M Leer 47 38 Voltage Repulatot CTEGUI 4 A ive i Ete ede 48 39 USB Schematic user ete OR YR LR RR EES SER CO ERO ERRARE RR RA TEC E IG 49 40 EmbeddedBlue eb100 SER OEM Bluetooth Serial Module 49 4 Preliminary AutoCad Skeleton of Casing esee 32 42 Preliminary AutoCad Illustration of Casing eee 53 43 Accessible Vital Signs Monitor Circuit Diagram esses 54 44 Bruising Caused by One Use of an Automatic Blood Pressure Cuff 56 45 Number of Current Home Heath Care Patients with Aides and Devices in 2000 58 46 Table ot Home Gare Cost Savings desea toux ii EUER 59 Fable 1 Blackfin Speerficatiofis oes ero ioco ea ds 42 Table 2 Core Clock Requirements co oce eee e ee A
85. rove the quality of life for those individuals with hearing and vision impairment who need to have their vital signs monitored This device will allow those individuals the ability to go home to recuperate while still being effectively monitored by their health care provider This is especially important in cases where home health care would be a treatment option for someone without visual or hearing impairments but not for someone with them Home health care is a growing industry Approximately 7 6 million individuals receive home care in the United States The Center for Disease Control reported that in the United States in 2000 317 600 individuals in home care were using medical devices Fig 45 Medical Total with medical devices 317 600 15 900 31 700 58 300 74 300 84 800 52 600 Blood glucose monitor llis 132 500 z 11 800 19 200 38 600 37 300 25 000 Endoral foodirig cw so cca eee ee ewes eae 30 700 t y 3 Intravenous WOY 2c o rrr mmn 52 300 17 100 x M M Dx NA A Dra Ld 114 600 A 18 200 25 700 43 400 19 900 Other respiratory therapy lt o oooo o 45 300 E 15 000 E id M AAA wea shoal IL EL 187 500 11 600 23 600 33 100 28 200 58 600 32 400 Figure does not meet standard of reliability or precision because the sample size is less than 30 if shown without an estimate If shown with an estimate the sample size is between 30 and 59 or the sample size is greater than 59 but has a relative stand
86. sed as the main microprocessor for the device For the PDIUSBDI2 an additional microcontroller is needed to make it easier to connect with the chip The microcontroller we chose is the PIC16F874 This allows for easy communication between the two chips By writing a computer program in the microcontroller we will be able to send the data received by the vital signs monitor to the USB device and then to the computer The following image shows the schematic of a how the USB device will connect with the microcontroller Fig 39 48 bab Conc habt parla 1 1 ape Redland Figure 39 USB Schematic 2 2 2 13 Bluetooth To increase accessibility we will add a Bluetooth option to transmit the data collected by the vital signs monitor to the client s computer wirelessly This will be in addition to the USB port We will purchase the EmbeddedBlue eb100 SER OEM Bluetooth Serial Module from A7 Engineering for 40 to integrate into our vital signs monitor to provide Bluetooth connectivity Fig 40 49 Parr Figure 40 EmbeddedBlue eb100 SER OEM Bluetooth Serial Module This module contains all the components of the Bluetooth stack on the board so that no additional host processor code is needed The interface between our host processor and the eb100 SER radio will be done through UART communication When a connection is made to another Bluetooth device the link will appear as a cabled serial connection which eliminates the need for any sp
87. sible home vital signs monitoring system The alternative designs show the changes that our vital signs monitoring system went through on its way to the final design the optimal design Following this section are the realistic constraints safety issues and impact of engineering solutions The realistic constraints and safety issues were factors that had to be kept in mind when designing our device The impact of engineering solutions section describes how our design affects different areas in society including the environment the economy and the global stage Next discussed is life long learning and how our device and its design has contributed to our life long learning The report concludes with a timeline for the construction of our device our budget and each team member s contribution to the report and design of the device Acknowledgements references and an appendix containing updated device specifications are also included 2 Project Design Engineering design is a process that involves research and revision This section contains the three design alternatives created for our accessible home vital signs monitoring system and the optimal design that was chosen In each design section any changes made are discussed followed by an explanation of each subunit of the design The optimal design was chosen because it keeps costs down while still being an effective home vital signs monitoring system It is also the design that is safest will la
88. sible to the hearing and visually impaired those with motor skills impairment and patients of all ages To create a reliable medical device existing technologies were brought together and combined into a single functioning unit As in the optimal design body temperature is measured by a thermistor circuit involving a Wheatstone bridge Blood oxygen saturation and pulse are calculated from pulse oximetry readings An automated blood pressure system using the oscillometric method measures blood pressure To measure respiratory rate a thermocouple registers the changes in the temperature of air being inhaled and exhaled This rate is analyzed by a microprocessor to determine the respiratory rate Finally a simple scale is used to measure weight By keeping realistic constraints in mind throughout the design process cost timelines resources we were able to design an affordable and manufacturable device Safety was always in consideration during the three alternative designs and the optimal design so as to design a vital signs monitor that would be a help to our clients health rather than a hindrance Aside from physical safety personal safety and privacy is ensured by the password protected website through which clients can upload their vital signs to their physicians or healthcare providers It is from all this that our accessible home vital signs monitoring system will improve quality of life by improving the quality of care 66 10 Refere
89. signs from home for the next 90 days Mat does not like devices that are very technologically advanced but lives with his vision impaired wife who loves the internet Sani is a 31 year old female who recently experienced a head injury from an automobile accident This accident left the right side of her body paralyzed her dominant side Sani is a lawyer and is now working part time from home She must sleep in a hospital bed and she administers pain medication to herself using an infusion pump Her doctor monitors her vital signs by a computer system that is installed in her home Sani does not want to appear sick to her family and friends She would like a vital signs monitoring device that blends in with the other furniture in her home Our last client is Dolores She is an 86 year old female who lives with her son his wife and their son Dolores is deaf and has severe arthritis She also has heart problems that cause her to receive infusions at home These infusions are normally administered by one of her family members Dolores grandson Tyler is 11 years old and he likes all kinds of electrical gadgets He loves to help his grandmother collect her vital signs and send them to her doctors on the computer 1 2 Purpose of the Project The purpose of this project is to create an accessible home vital signs monitoring system Although there are already similar devices on the market it is our goal to design a monitoring system that meets our clie
90. signs on a USB flashdrive These measurements could then be uploaded to the secure website and accessed by doctors anywhere 6 Life Long Learning During the research of this design we were introduced to new and challenging engineering applications In updating our processing technique we learned about the Blackfin and digital signal processing Although we have already learned about FIR and IIR filters thus far in our engineering curriculum we were now able to apply these concepts to a real life situation Through researching digital signal processing we were able to compare it to traditional microcontroller design and see the differences Digital signal processing is not only substantially faster it also eliminates additional hardware associated with analog circuits Although analog circuits are cheap and easy to assemble software based DSPs provide flexibility in modification and maintenance We learned to integrate microcontroller based data gathering with digital signal processing to achieve a cheaper more efficient way of data analysis Also the text to speech function in our design was a new and exciting function to learn about Since none of us have ever worked with such a unique and advanced tool it made the research enjoyable and informative There are many devices out there used for speech synthesis but we needed to find the one that would be compatible with the microcontroller we selected as well as capable of converting the text o
91. so uses a new method to measure blood pressure without unnecessary constriction of the patient s limb U S patent number 5 613 495 by Mills et al is for a high functional density cardiac monitoring system for captured windowed ECG data It is a very small device that is lightweight and worn on the wrist It uses dry skin electrodes that come in contact with the patient s skin to take readings This device also includes a speaker and method for transmitting the recordings over a phone line U S patent number 5 553 609 by Chen et al is an intelligent remote visual monitoring system for home health care service This device is a way for a health care professional to monitor a patient in their home from a remote location This is done through normal telephone lines and uses two main databases for storing and sending information Finally a vital sign remote monitoring device patented by Money et al U S patent number 5 919 141 describes a device for the remote monitoring of a hospitalized patient s vital signs This device provides interfaces for pulse oximetry ECG respiration temperature and blood pressure transducers Readings are sent by a RF transmitter to a remote monitoring station 1 4 Map for the Rest of the Report The remainder of the final report covers design budget and other engineering considerations The next section details the design process by discussing the three alternative designs and the optimal design of the acces
92. ssure sensors pressure release valves and air pumps Blood pressure waveforms were studied and the oscillometric method for blood pressure measurement was introduced to us In addition to learning new technical engineering applications senior design has also taught us to work and function as a group By working as group we learned to interact and communicate with each other to assess and resolve problems as well as rely on each other to make deadlines Since communication is an essential element of being an engineer working on these skills before we graduate will give us an edge over the majority of graduating engineers Whether we will be working with an engineering design team a team of healthcare professionals or in a corporate environment when we graduate we will need to use these group skills we are currently developing to drive a successful career 61 7 Budget and Timeline 7 1 Budget Table 3 Design Budget Part Cost Shipping and Handling res oco Snap in Style Pushbutton Mouser AC DC Power Converter shop com 29 95 10 47 5 68 each 6 49 9V Rechargeable Battery Digital Scale Homedics 19 95 6 95 PIC Microprocessor 5 84 Unknown Philips USB Chip 3 49 6 41 Linear Voltage Regulator S Arm Cuff CVS 9 99 N A Digital Thermometer Vicks 11 99 N A CTS Single Head Micro Air Pump 48 00 9 18 MPX2200 Pressure Sensor Digikey 12 76 11 41 827 37 each
93. st the longest and be the easiest to manufacture 2 1 Design Alternatives 2 1 1 Design 1 2 1 1 1 Objective Our accessible home vital signs monitoring system will have the capability to non invasively gather the client s heart rate blood pressure blood oxygen saturation level and body temperature and then send this data to their healthcare provider The data will be sent via a USB flash drive to a password protected encrypted website This accessible home vital signs monitoring system design is an accurate and consistent way to obtain a patient s vital signs regardless of the caregiver s skill level The buttons on the front panel of the monitor will be large and printed with either Braille or a universal symbol allowing patients who are vision impaired or who have arthritis to successfully operate the monitor Also to accommodate vision impaired clients a text to speech function will be implemented to allow the monitor to audibly communicate current vital signs readings In addition four bright LCD screens with wide viewing angles will be used to display the patients vital signs A visual and audio alarm will be installed to alert clients if their vital signs are abnormal To collect the data medical transducers will be commercially purchased and integrated into the accessible vital signs monitoring system The items to be purchased are a finger pulse oximeter probe an oral temperature probe and an automatic blood pressure cuff 2
94. t Current to voltage converter circuit Sample and hold circuit LCD T A RE Bandpass filter Amplifier Photodiode detector PES NIR LED driver Red LED driver Timing circuit Timing circuit circuit circuit Automatic gain Automatic gain control circuit control circuit Low pass filter Low pass filter Figure 14 Pulse Oximeter Circuit Block Diagram To build the finger probe that we will use with our device we will need a red LED a NIR LED and a photodiode The LEDs will be placed opposite the photodiode within a casing that can be clipped to a finger Fig 15 LEDs Probe __Lasing Finger Photodiode Figure 15 Finger Probe Diagram One LED will work at a red wavelength 660nm and the other at a near infrared NIR wavelength 910nm Also in the probe is a photodetector that will detect the light transmitted through the finger The red LED used in the probe will have been manufactured to give high intensity output and the NIR LED will have been designed to 30 be pulsed so that its peak power can be increased without increasing its average power By pulsing both light sources only one photodiode is needed to detect the light transmitted through the finger 16 To transmit light the LEDs need to be driven by a constant current source This can be done by a non inverting op amp combined with a FET Fig 16 In this circuit the current driving the LED is given by ILep Vin 1
95. t Mat who is blind and cannot see the monitor Even though his wife is around to help him she is also vision impaired The output text from each pin on the microcontroller will need to be converted to sound To do this we will use the Magnevation SpeakJet IC Fig 34 It is an 18 pin IC which uses a mathematical sound algorithm to control an internal five channel sound synthesizer to produce sound The SpeakJet can be controlled by a single I O line from the Blackfin 13 Since this microchip requires phonetics and not text the TTS256 Text to Code IC will have to be used in conjunction with the SpeakJet The TTS256 is an 8 bit microprocessor programmed with letter to sound rules This built in algorithm allows for the automatic real time translation of English ASCII characters into allophone addresses compatible with the Magnevation SpeakJet Speech Synthesizer IC This IC is Compatible with Basic Stamp OOPic Pic and any processor with a serial port like our microchip 13 We will use pin 5 TX to output the phonetics from the SpeakJet and pin 18 RX to receive the data from the Blackfin Fig 35 The pin diagram of the TTS256 is shown below The final sound will be sent from the Voice Output pin 718 of the SpeakJet using 5V and a speaker Since the SpeakJet is preconfigured with 72 speech elements 43 sound effects and 12 DTMF touch tones we will also use the SpeakJet to produce an alarm when the vital signs are out of range range to be
96. t Recommend preventing large amounts of dust from settling on the device Operating Temperature 50 105 F Storage Temperature 40 110 F 70 12 2 Purchase Requisitions and Quotes PURCHASE ORDER REQUISITION UCONN BME SENIOR DESIGN LAB Instructions Students are to fill out boxed areas with white background Each Vendor will require a different purchase requisition Date November 25 2006 Student Name Michael Kapinos Team Total Expenses Ship to University of Connecticut Biomedical Engineering U 2247 260 Glenbrook Road Storrs CT 06269 2247 Attn Project Name Accessible Home Vital Signs Monitor Lab Admin only FRS Student Initial Budget Student Current Budget Project Sponsor ONLY ONE COMPANY PER R EQUISITION Catalog Description Unit Amount 693 1241 6634 1121 Snap in Style Pushbutton 103 20 0 00 0 00 0 00 0 00 0 00 Comments Price Quote File Name Yes or No Vendor Accepts Purchase Orders Vendor Mouser Electronics Address www mouser com Phone Contact Name 0 00 103 20 Shipping Total Authorization 71 PURCHASE ORDER REQUISITION UCONN BME SENIOR DESIGN LAB Instructions Students are to fill out boxed areas with white background Each Vendor will require a different purchase requisition Date Nov
97. t and output the data like a microcontroller but use the digital signal processing features to analyze and filter the signals FIR and IIR filters The Blackfin will function like the traditional microcontroller taking the electric signals from the transducer passing them through an analog to digital converter and processing the information Like the PIC microcontrollers the Blackfin contains an internal analog to digital converter There are many advantages for us in using digital signal processing rather than traditional 100 microcontroller functions Microcontrollers can be cheap and easy to assemble but are difficult to calibrate and modify Using DSP one can more easily design and modify their work due to the fact that it is all computer based Thus one can rely on their software based filters much more DSPs are also much faster than microcontrollers A typical PIC microcontroller has a clock speed of about 20 MHz whereas the Blackfin has a clock speed of 350 MHz Table 2 We will use the PF pins I O ports on microcontrollers on the Blackfin to function as inputs for the transducers and outputs for the LCD screens and speaker Due to the Blackfin s abilities it should be the only microprocessor we need for our device We also chose to use the Blackfin due it its versatility in programming code The Blackfin can take C C code as well as LabVIEW VI s Since we have had more experience using LabVIEW we felt that LabVIEW would be a m
98. t to an automatic gain control circuit The gain control circuit adjusts the light intensity from the LEDs so that the d c level always remains at the same value whatever the thickness of the patient s skin tissue etc This circuit is implemented by feeding the d c signal to one input of a differential amplifier The other input to the amplifier is a constant reference voltage The output of the differential amplifier the voltage difference between the two inputs is used to generate the voltage that sets the value of the LED currents 16 Heart Rate Pulse oximetry will also be used to determine heart rate There are pulsatile signals detected in the intensity of the detected light by the photodiode These pulses can be counted within a given time period to determine heart rate This will be done by the microprocessor and displayed on an LCD screen 2 1 1 4 Non Invasive Blood Pressure One way in which blood pressure can be measured non invasively is through use of an occlusive cuff Automated blood pressure measurement includes two systems the cuff control system and the microphone system to measure the Korotkoff sounds generated The cuff control system involves inflating the cuff then deflating it at a slow rate to produce the Korotkoff sounds A complex circuit is used to detect the Korotkoff sounds The circuit must differentiate between the Korotkoff sounds background noise and the heart beating It also must determine which phase a s
99. t value the systolic pressure determined The microprocessor will continue to monitor the blood pressure readings and diastolic pressure will be taken when the voltage drops below the threshold voltage for 2 pulsations After the diastolic pressure is determined a command from the microprocessor will deflate the cuff quickly and completely 37 Systole pressure detected Figure 26 Block Diagram of Automatic Blood Pressure Measuring System Due to the safety issues that arise with automatic blood pressure systems we have incorporated a kill switch into our design Fig 26 18 If at any time during the blood pressure measurement the user wants to stop the inflation of the cuff and rapidly deflate it they just need to press the vital signs monitor On Off button This will cut power to the whole device and open the pressure release valve This method bypasses the microprocessor avoiding any software bugs that an emergency stop button might encounter As stated previously the automated blood pressure system will be calibrated experimentally This will be done through establishing a threshold voltage by which correct pressure measurements for systolic and diastolic pressures can be made Final 38 testing of the device will be done by comparing its blood pressure readings to those of a sphygmometer In the testing the sphygmometer will be operated by a nurse or other individual who is familiar with manually measuring blood
100. th Braille or Universal Symbols for the vision impaired The monitor includes rechargeable back up batteries in case of power failure or if the client just does not to be homebound by their health monitoring needs 1 Introduction To fully understand this project and its drive certain background information is necessary This section explains the purpose of our design and our client Also to give an understanding of the technology this section contains information on vital signs monitors and similar devices that monitor health and wellness 1 1 Background With the aging baby boomer population home health care is a growing and changing industry The advent of telemedicine and advanced communications technology has allowed patient monitoring to move from the hospital to the home By monitoring patients statuses remotely health care facilities can free up hospital beds and doctors time for more critical patients An integral part of remotely monitoring a patient s condition is the vital signs monitor There are many clients who are in need of an accessible home vital signs monitoring system To make this device as accessible as possible we have to address the many needs of our clients An overview of these needs can be seen in three of our clients Mat Sani and Dolores Mat is a 52 year old male in good physical condition He is blind and works as a radio commentator Mat just had a small stroke and his doctor wants to monitor his vital
101. tient s vital signs regardless of the caregiver s skill level To accommodate all users including our clients the monitoring system was designed as simple and user friendly as possible To maximize the simplicity of our design and make it accessible to all of our clients the buttons on the front panel of the monitor will be large and printed with either Braille or a universal symbol allowing patients who are vision impaired or have arthritis to successfully operate the monitor Also to accommodate vision impaired clients a text to speech function will be implemented to allow the monitor to audibly tell the patients what their current vital signs are In addition six bright LCD screens with wide viewing angles will be used to display the patients vital signs A visual and audio alarm will be installed to alert clients if their vital signs are abnormal An illustration of our design followed by a flowchart of our system operation can be seen in Figs 9 and 10 24 Figure A 10cm Alarm Handle Crystalfontz LCD Screen 12cm Viewing Area 10cm 1 gt Blood Oxygen Level Heart rate ico sse 55 BPM sna Area 2 4cm Instruments 20cm Blood Pressure Body Temperature Respiratory Rate 1201180 98 6 F Exa 15 2 MENE EX i c 41cm Speaker Figure B On Off Instrument Ports USB Port 20cm Figure C Power Cable 20cm Ios A 41cm Figure 9 Illustration of Design 23 Power Button
102. to voltage conversion Fig 19 The photodiode provides a high junction resistance so the op amp should be a FET type with high input impedance 16 The negative input of the op amp acts as a virtual ground making the output of the op amp v IR Thus it is common practice to make the value of R as high as tens of MQ with the value of C as 47pF 16 C Figure 19 Current to Voltage Photodiode Conversion Circuit 32 Because the LED light is pulsed sample and hold circuits are needed to reconstitute the waveforms at each of the two wavelengths The timing circuits that were used to control the red and NIR LED drivers also are used to provide the control pulses for their corresponding sample and hold circuits 16 A simple sample and hold circuit can be created from a FET switch capacitor and op amp Fig 20 MIY vs c3 T in gt 0 Figure 20 Sample and hold Circuit Once the signal goes through the sample and hold circuit it is sent through a band pass filter with cutoff frequencies 5Hz and 5Hz to eliminate high frequency noise and the d c offset Then it is amplified resistor values to be determined and sent through an A D converter and the microprocessor to be analyzed A lookup table stored in the microprocessor will be used to calculate SpO values This signal is also sent through a low pass filter f 1Hz to extract the d c value of the transmitted signal which is then sent to an automatic gain
103. urrent home health care patients by type of aids devices used sex and race United States 2000 Current Home Care Patients Feb 2004 http www cdc gov nchs data nhhesd curhomecare00 pdf 13 SpeakJet User s Manual Magnivation 2004 lt http www speechchips com downloads speakjetusermanual pdf gt 14 Safe Circuit Design All About Electric Circuits 2003 lt http 72 14 209 104 search q cache HYM2hyPm4rcJ www allaboutcircuits com vol_1 chpt_3 8 html 67 circuit design safety amp hl en amp gl us amp ct clnk amp cd 1 gt 15 Townsend Neil Non Invasive Blood Pressure Medical Electronics Michaelmas Term 2001 lt http www robots ox ac uk neil teaching lectures med_ elec notes7 pdf gt 16 Townsend Neil Pulse Oximetry Medical Electronics Michaelmas Term 2001 lt http www robots ox ac uk neil teaching lectures med_elec notes6 pdf gt 17 Volk Karl R Using thermistors in temperature tracking power supplies EDN August 2 2001 lt http www edn com article CA149117 html gt 18 Wattanapanitch Woradorn and Warut Suampun Portable Digital Blood Pressure Monitor Cornell University lt http www people cornell edu pages ws62 gt 19 Webster J G ed Design of Pulse Oximeters Philadelphia IOP Ltd Publishing 1997 11 Acknowledgements We would like to acknowledge the following people to thank them for their support and assistance with
104. use of the device might cause Since 55 this is a medical monitoring device one of its safety constraints is that it should not be explosive It should not spark or create flames which could cause an explosion when used in the presence of pure oxygen Most components of our design are relatively benign provided that basic electrical safety is followed but a major point of health and safety constraint was the design and incorporation of the automatic blood pressure measuring device Self inflating blood pressure cuffs can cause injury if not properly calibrated and used Fig 44 Figure 44 Bruising Caused by One Use of an Automatic Blood Pressure Cuff 15 Bruising can result if the cuff inflates too much Pain and circulation cutoff can occur if the cuff does not deflate and at the extreme this could lead to tissue death Our accessible vitals signs monitoring system has really no political constraints but it does have social and privacy constraints Part of our system includes the transmission of vitals signs of the internet to a health care provider To protect patient privacy and abide by the Health Insurance Portability and Accountability Act HIPAA the transmission of vital signs will be done via a secure password protected website This will protect our clients personal information while still giving them flexibility in the transmission of their vital signs to their physicians or HMOs This is an important and valid constra
105. utput from the microcontroller to sound Most algorithms associated with speech chips cannot convert English text straight to audio which is why we integrated the TTS256 Text to Code microcontroller to convert text to phonetics which is compatible with the SpeakJet Through designing the thermometer for the accessible vital signs monitor we have learned about the Steinhart Hart equation and the properties of thermistors It is important to realize that thermistors behave nonlinearly and to understand what effects this has on designing a thermometer In order to use the thermistor output it must be linearized This can be done over a small temperature range but any readings outside the 60 temperature range will be increasingly inaccurate the farther away they are This means that one should only use an oral thermometer to measure oral body temperature not air temperature or a cold beverage We learned about the optical properties of blood and the Beer Lambert law to design a pulse oximeter circuit Also from the pulse oximeter we saw the application of transistors to switching and timing Research into an automated blood pressure measurement system highlighted the importance of control systems in medical devices Even for something as seemingly benign as an automatic blood pressure cuff system safety precautions have to be taken to ensure that a patient is not harmed through the use of the device This design also required us to learn about pre
106. will be calibrated through UART communication with any extra equipment necessary provided by the BME 252 lab It will be programmed to set up a network with the Bluetooth USB dongle when it detects it The Bluetooth system will be tested by acquiring vitals signs from the monitor and sending them to a computer in the design lab to which the USB dongle is installed The vital signs monitor will be placed at different ranges within 10 meters to determine signal strength at different ranges and the optimum range for data transmission 2 2 2 14 Pushbuttons Along with our design we decided one of our most important features was going to be the buttons that were involved We need to have our buttons customizable so we can include a universal sign and also Braille so they can be used by people vision 50 impairment After searching for a while we determined that there were not many sites which made this option available but we did find one called http www grayhill com pushbuttons Through this site it is possible to determine the option of your pushbuttons including a Braille option We will also be able to choose what colors we want the buttons to be The model button that will fit our project the best is a rectangular button that is about 15 by 20 millimeters in size These buttons are very easy to secure by a short simple process The buttons require a proper size hole to be drilled in the area where the buttons will be placed The buttons will t
107. xpenses Ship to University of Connecticut Lab Admin only Biomedical Engineering FRS m U 2247 260 Glenbrook Road Student Initial Budget Storrs CT 06269 2247 Student Current Budget mr Attn Project Sponsor prn Project Name Accessible Home Vital Signs Monitor ONLY ONE COMPANY PER REQUISITION Catalog Description Unit QTY Unit Price Amount 122mm 44mm PCB Size Green LED CFAH1602L Backlight 6 27 37 164 22 0 00 0 00 0 00 0 00 0 00 0 00 0 00 0 00 0 00 0 00 0 00 0 00 0 00 0 00 Comments Price Quote Shipping 12 75 File Name Total 176 97 Yes or No Vendor Accepts Purchase Orders Vendor Crystalfontz Address www crystalfontz com Authorization Phone 1 888 206 9720 Contact Name 80 PURCHASE ORDER REQUISITION UCONN BME SENIOR DESIGN Instructions Students are to fill out boxed areas with white background LAB Each Vendor will require a different purchase requisition Date November 25 2006 Team Project Name Accessible Home Vital Signs Monitor Student Name Robert Croce Total Expenses Ship to University of Connecticut Biomedical Engineering FRS U 2247 260 Glenbrook Road Student Initial Budget Storrs CT 06269 2247 Student Current Budget Attn Project Sponsor Lab Admin only ONLY ONE COMPANY PER REQUISITION Catalog Description Unit Unit QTY Price Amount ADSP BF537BBCZ5A Blac

BME 290 Final Report - Biomedical Engineering

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