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Final Report - Biomedical Engineering

1. Patient View Clinician View J Lows 4 University of Connecticut Raw Data Signal Analysis Tabulated Results MASSETER CLENCH TIME minutes Right Masseter Right Masseter Right Temporalis Bruxism Events Displays the total amount of time 0 00 0 03 2 spent clenching in minutes Left Masseter Left Temporalis Left Masseter 0 02 0 03 Events 2 TEMPORALIS EVENT TIMES Right Temporalis Right Masseter Left Masseter RightTemporalis Left Temporalis Records the exact 5 Ao p n EE Bruxism Events P times The user FER PM EE PM oum PM FER PM 4 can scroll through 4 28 2011 4 28 2011 4 28 2011 4 28 2011 Left Temporalis FANE using the arrows Bruxism Events E P Figure 38 Tabulated data for easy diagnosis of bruxism It can be seen that the results of the tabulated results are relatively accurate This method will eliminate the need for the clinician to review hours of EMG data and count the number of bruxism events The algorithm for detection is relatively simple but improvements can be made to increase the accuracy of bruxism detection The client has been provided with LabVIEW 2010 development software so changes to the code can be performed in the future The patient will not have access to the code because the application will be an executable file prohibiting any program changes Two members of this design project have Temporomandibula
2. TLO74V AI BI 40 105 C TLO74C AC BC 0 70 C o Example TLO74IN Dual In Line Package 050 D Smell Out ne Package 50 also avaliable In Tape 8 Reel DT Output 4 Inverting Input 4 Non inverting Input 4 Non inverting Input 3 Inverting Input 3 Output 3 March 2001 TMJD Diagnostics System Senior Design Spring 2011 1 11 62 National Instrument s USB 6008 OEM is shown below The USB 6008 is a critical component of this project and therefore the entire datasheet is available for viewing It may also be accessed at http www ni com pdf products us 371728b pdf C o RR UALLZA ZALZZZZZZLLLlu LES USER GUIDE NI USB 6008 6009 OEM This document provides information about the dimensions connectors and other components of the National Instruments USB 6008 6009 OEM device For more information about the device refer to the USB 6008 6009 User Guide and Specifications document available at com manuals Caution There product safety electrogmagnetic compatibility CE marking compliance claims made for the NI USB 6008 6009 OEM devices The NI USB 6008 6009 OEM device is intended to be used as a component of a larger system National Instruments can help developers meet their compliance requirements The end product supplier however is responsible for conforming to any and all compliance requirements Figure 1 USB 6008 6009 OEM Devic
3. TMJD Diagnostics System Senior Design Spring 2011 7 End data acquisition by Sleep gt clicking STOP in LabVIEW program Turn computer Place device ON and confirm over head Bluetooth adjust as connectivity necessary Turn device Take off device turn device OFF Figure 4 Process to activate the device Figure 4 displays the device s user friendly minimal interface the patient does not have to do much to acquire data The reader should note that Alternative Design 1 is a viable option for future applications Alterations to this design concept were implemented to account for time and other constraints ALTERNATIVE DESIGN II An alternative design to the one described previously introduces a change to the mechanical design of the device while maintaining the same modality of signal acquisition and data collection analysis and display The proposed mechanical design resembles that of the existing diagnostic device BiteStrip As in Alternative Design 1 two reusable skin electrodes will be used to collect the electromyography data from one muscle The corresponding circuitry will perform corresponding amplification and filtering to the signals The data will then be sent via Bluetooth to a computer provided to the patient This time however Instead of enclosing the circuitry in the hat worn by the patient it will be integrated into a mini
4. pV p p tk 10k 100k 1M 10M 100M SOURCE RESISTANCE f Figure 2 Total Voltage Noise vs Source Resistance One Technology Way P O Box 9106 Norwood MA 02062 9106 U S A Tel 781 329 4700 World Wide Web Site http www analog com Fax 781 326 8703 Analog Devices Inc 1999 Senior Design Spring 2011 61 5 TL074 low noise JFET quad operational amplifier is shown below TL074 TL074A TL074B LOW NOISE J FET QUAD OPERATIONAL AMPLIFIERS WIDE COMMON MODE UP TO Vcc AND DIFFERENTIAL VOLTAGE RANGE LOW INPUT BIAS AND OFFSET CURRENT LOW NOISE e 15nV Hz typ OUTPUT SHORT CIRCUIT PROTECTION HIGH INPUT IMPEDANCE J FET INPUT STAGE LOW HARMONIC DISTORTION 0 01 typ INTERNAL FREQUENCY COMPENSATION LATCH UP FREE OPERATION HIGH SLEW RATE 13V us typ DESCRIPTION The TLO74 TLO74A and TLO74B are high speed J FET input quad operational amplifiers incorpo rating well matched high voltage J FET and bipo lar transistors in a monolithic integrated circuit The devices feature high slew rates low input bias and offset currents and low offset voltage temper ature coefficient PIN CONNECTIONS top view Inverting Input 1 Non inverting Input 1 Vec Non inverting Input 2 Inverting Input 2 Output 2 DIP 14 Plastic Package D 014 Plastic Micropackage ORDER CODE Temperature Range 074 55 125
5. events occur must also be recorded during the session which poses additional challenge This design is certainly worth considering because of the drastic reduction in cost However the memory availability of integrated circuits needs to be researched more order to determine if this design is feasible Due to the client s request that a notebook computer accompany the device this design is not considered optimal at this time 2 1 Optimal Design 2 1 1 Objective The TMD Diagnostics Device utilizes electromyography EMG to obtain biosignals from the muscles involved in mastication including the left and right temporalis muscles and the left and right masseter muscles These EMG signals will be used to determine if the patient is bruxing or clenching during sleep two major contributing factors to temporomandibular joint disorder TMD EMG is currently utilized in TMD sleep studies with significant efficacy in determining bruxing events However sleep studies are expensive and uncomfortable for the patient resulting in data that is inconsistent with their sleep habits This device allows the patient to perform a comfortable EMG study in their home environment and acquire accurate data The signals are obtained from disposable electrodes without the use of adhesive gel providing a superior level of comfort for the patient The device is comprised of a modified Neuroband a wearable device traditionally used for electroencephalog
6. Action About 1 Saving Images Select Folder Save TEROOO2 BME 100 1 00 25 0ms CH1 gt 1 30 Current Folder 4 4 Figure 18 Bandpass filter at 15 Hz It is evident from Fig 18 that the bandpass filter sufficiently attenuated low frequencies The input signal was 4 44 V pk pk at 15 Hz The output signal was 120 mV pk pk resulting in a gain of 0 027 This filtration was sufficient to meet our needs Tek Trig d Pos 0 0006 SAVE REC Action 2 Saving Images Select Folder Save TEKOO03 BMP CH1 1 00 CH2 100v 1 00ms CH1 Z 1 90 Current Folder is AY Figure 19 Bandpass filter at 200 Hz It is evident from Fig 19 that the bandpass filter sufficiently passed middle frequencies The input signal was 5 08 V pk pk at 200 Hz The output signal was 3 92 V pk pk resulting in a gain of 0 772 Thus the bandpass filter sufficiently passed TMJD Diagnostics System Senior Design Spring 2011 20 middle frequencies which is important because 200 Hz frequencies are within the bandpass of EMG signals Tek Trig d M Pos 0 000s SAVE REC Action 2 Select Folder Save 0004 CH1 1 00V CH2 1 00V 1 00ms CH1 Z 1 90 Current Folder is Figure 20 Bandpass filter at 450 Hz It is evident from Fig 20 that the bandpass filter sufficiently passed upper middle frequencies The input signal was 5 08 V pk pk at 200 Hz The output signal was 2 4
7. a S 1 1 1 1 3 1 1 1 6 24 03 610 PM 6 24 04 000 PM 6 24 04 500 6 24 05 000 6 24 05 500PM 6 24 06 000 6 24 06 500 6 24 07 000PM 6 24 07 500 6 24 08 000 PM 6 24 08 610 PM 4 28 2011 4 28 2011 4 28 2011 4 28 2011 4 28 2011 4 28 2011 4 28 2011 4 28 2011 4 28 2011 4 28 2011 4 28 2011 a lt Figure 48 TMJD Results Application reading EMG files from the four muscles TMJD Diagnostics System Senior Design Spring 2011 42 View EMG Final 2 vi nl Raw Data Signal Analysis Tabulated Results MASSETER Right Masseter Bruxism Events Displays the total CLENCH TIME minutes Right Masseter Right Temporalis Bruxism Events Hotmail mariana_md Document Microsof amount of time 05151 0 22 4 spent clenching Left M t in minutes Left Masseter Left Temporalis asseter 0 00 0 22 Bruxism Events ir TEMPORALIS EVENT TIMES Right Temporalis Right Temporais Left Masseter Right Masseter Left Tempora R d th t a a ig lasseter emporalis Bruxism Events bruxism event 9 9 ze 9 9 times The user esas 29 51 PM sese 4 can scroll through EZEIZ zu the event times Soe 8 49 36 8 49 36 PM Left Temporalis Vising tha arrows 2 LabVIEW 10 0De Figure 49 Signal Analysis tab of the TMJD Results Application showi
8. Fourth order Butterworth cascading lowpass and highpass active filters were initially because they only require two op amps and minimal external components The filters were designed using Microchip s Filterlab software to design the Butterworth saving a significant amount of time Some of the resistor and capacitor values were altered slightly so that realistic components could be ordered The lowpass filter is shown in Fig 14 TMJD Diagnostics System Senior Design Spring 2011 17 C4 0 15uF VCC 0 022uF 9v 9 2 WiNna001GP LOWPASS MWA 10 5kQ 16 2 0 120 V i qe F rms a u 60 Hz L ro En Figure 14 Fourth order lowpass Butterworth filter with cutoff frequency 500 Hz The cutoff frequency of this filter is 500 Hz to ensure that frequencies below the 3 dB passband are attenuated TL074 quad op amps were selected due to their low noise and distortion They are also cost effective and will save space on the PCB due to their quad op amp package An AC simulation was performed using Multisim 11 0 as shown in Fig 14 AC Analysis Magnitude ap 7001 100n 1 4 7 10 40 70 100 400 700 1k 4k 7k 10k 40k 100k Frequency Hz jg lowpass Figure 15 AC simulation for the lowpass filter It is evident from Fig 15 that the filter sufficiently attenuated frequencies above 500 Hz Protoboard testing of the lowpass filter was conducted a
9. The device provided the total number of bruxing events as well as the lasting time of each bruxing event Finally the recorded data was transmitted into the computer via serial port The device was equipped with EEPROM and the data is recorded on the memory to the maximum of 676 data sets in one night Although the authors who carried out the study verified the accuracy of the device and the subjects of the study declared that it was easy to use this device does not provide comfort and mobility to the patients due to the presence of wires Moreover serial communication limits the speed of data acquisition The components of the bruxism monitoring device is shown in Fig 2 The test setup for data acquisition is shown in Fig 3 TMJD Diagnostics System Senior Design Spring 2011 4 button switch Figure 2 Components of the bruxism monitoring and analysis device developed by Sakagami Horii Matoba Kato and Kawanami Masseter Figure 3 Left The temporalis and masseter muscles Center Electrodes attached to the cheek for the data acquisition from the masseter muscles and to the chin for earthing Right Electrodes attached to the temple for the data acquisition from the temporalis muscles and to the forehead for grounding TMJD Diagnostics System Senior Design Spring 2011 5 1 3 2 Patent Search Results The Bitestrip described above has applied for relevant patents and clinical studies are in process in wel
10. and other factors with Bluetooth protocol Initially reusable electrodes were considered to be optimal for this project due to their repeated usage capability They did provide signal quality similar to the disposable adhesive surface electrodes however they were removed from the final product design due to their inability to maintain solid connection to the skin for extended periods of time They also presented problems with sanitation as they were difficult to sanitize with conventional methods and might pose health risks as the device is transferred to other patients 12 2 Microcontroller Code in Embedded C Joe RE KOR EE University of Connecticut Biomedical Engineering BME 4910 Senior Design Temporamandibular Joint Disorder Diagnostics Device Michael Jorgensen Kerry Semle Mariana Hu This code is free to be used by anyone without the consent of the authors A ERE BEE AE EA RE ope sk obe eo A AE A ERE eR EE ok eroe define F_CPU 100000001 include lt avr io h gt include lt avr interrupt h gt include lt util delay h gt Global variables for battery level indicator function unsigned int max value 0 TMJD Diagnostics System Senior Design Spring 2011 55 unsigned int 0 unsigned int decimal unsigned int data unsigned int wholeVin unsigned int tenth_decimal Globa
11. 0 0 25 2 5 6 24 00 309 6 24 01 000 PM 6 24 01 500 PM 6 24 02 000 PM 6 24 02 500 PM 6 24 03 000 PM 6 24 03 500 PM 6 24 04 000 6 24 04 500 6 24 05 309 4 28 2011 4 28 2011 4 28 2011 4 28 2011 4 28 2011 4 28 2011 4 28 2011 4 28 2011 4 28 2011 4 28 2011 Time Right Masseter a l 0 5 E 0 25 0 25 9 57 1 1 1 1 1 1 6 24 27 509 PM 6 24 28 000 PM 6 24 28 500 6 24 29 000 PM 6 24 29 500 PM 6 24 30 000 PM 6 24 30 500 PM 6 24 31 000 PM 6 24 31 500 PM 6 24 32 000 PM 6 24 32 509 PM 4 28 2011 4 28 2011 4 28 2011 4 28 2011 4 28 2011 4 28 2011 4 28 2011 4 28 2011 4 28 2011 4 28 2011 4 28 2011 Time Left Temporalis a 4 0 5 lt 0 5 1 1 1 1 1 1 1 1 1 1 1 6 23 58 311 6 23 59 000 6 23 59 500 6 24 00 000 6 24 00 500 6 24 01 000 6 24 01 500 6 24 02 000 6 24 02 500 6 24 03 311 4 28 2011 4 28 2011 4 28 2011 4 28 2011 4 28 2011 4 28 2011 4 28 2011 4 28 2011 4 28 2011 4 28 2011 Time Right Temporalis al E 0 5 2 px o amp Em 1 1 1 1 1 1 1 1 k 1 1 6 24 03 610 PM 6 24 04 000PM 6 24 04 500 6 24 05 000 6 24 05 500 6 24 06 000 6 24 06 500 6 24 07 000 6 24 07 500 6 24 08 000 PM 6 24 08 610 4 28 2011 4 28 2011 4 28 2011 4 28 2011 4 28 2011 4 28 2011 4128 2011 4 28 2011 4 28 2011 4 28 2011 4 28 2011 Figure 43 Clinician View tab of TMJD Diagnostics Application After awak
12. 10 40 70 100 400 700 1k 4k 7k 10 40k 100k Frequency Hz ya esten n Figure 24 60 Hz notch filter AC simulation It is evident from Figure 24 that the filter sufficiently attenuates 60 Hz noise while passing nearby frequencies Protoboard testing was conducted on the 60 Hz notch filter and the results are shown in Fig 25 TMJD Diagnostics System Senior Design Spring 2011 23 Tek Triq d Pos 0 0005 SAVE REL action Saving Images Select Folder Save TEROOO BME 200v CH2 T mV T 0 ms CH2 2 4 8mv 8 10 16 45 118 0 74Hz Figure 25 Protoboard testing of the 60 Hz notch filter It is apparent from Fig 25 that the output signal shown in blue is distorted and noisy The input signal was 5 0 V pk pk at a frequency of 120 Hz The output signal was approximately 200 mV pk pk resulting in a gain of 0 04 Thus the filter significantly attenuated a 120 Hz signal which should not occur Additional testing of the notch filter was conducted using a TL074 op amp The output resulted in no filtering at all which was confirmed by a Multisim AC analysis The AC simulation of the 60 Hz notch filter cannot be verified by Filterlab due to the restriction of building bandstop filters but it may be necessary in the future to confirm the simulation with a program such as PSpice The 60 Hz notch filter was removed from the analog circuit and a 60 Hz notch filter was implemented into the LabVIEW program
13. 1903 12 31 19 name Thu Apr 28 2011 Right Masseter Imv 12 31 1903 12 31 1903 12 31 1903 Files E 21 Left Temporalis View EMG Final 2 vi Right Masseter Left Masseter i e ee a 4 University of Connecticut Raw Data signal Analysis Tabulated Results lvi J Left Masseter 0 5 0 25 pls 0 25 3 57 j i 7 00 00 000PM 7 00 00 500PM 7 00 01 000PM 7 00 01 500PM 7 00 02 000PM 7 00 02 500PM 7 00 03 000 7 00 03 500 7 00 04 000PM 7 00 04 500PM 7 00 05 000 PM 12 31 1903 12 31 1903 12 31 1903 12 31 1903 12 31 1903 12 31 1903 12 31 1903 12 31 1903 12 31 1903 12 31 1903 12 31 1903 Time Right Masseter El Pil 0 5 0 25 15 ip 3 57 1 1 1 1 1 6 23 49 608 6 23 50 000 6 23 50 500 6 23 51 000 6 23 51 500 6 23 52 000 6 23 52 500PM 6 23 53 000PM 6 23 53 500 6 23 54 000 PM 6 23 54 608 4 28 2011 4 28 2011 4 28 2011 4 28 2011 4 28 2011 4 28 2011 4 28 2011 4 28 2011 4 28 2011 4 28 2011 4 28 2011 Time 2 Left Temporalis 3T E 0 5 0 500 PM 7 00 05 000 PM ZJ Hotmail mari Ty Documenti J View EMG Fin Figure 47 TMJD Results Application reading EMG file selected TMJD Diagnostics System Senior Design Spring 2011 41 The raw EMG signals are disp
14. 4 28 2011 4 28 2011 4 28 2011 4 28 2011 4 28 2011 4 28 2011 4 28 2011 4 28 2011 Time a L Left Temporalis RMS 124455178PM 12 44 56 000 PM 1244 56500PM 12 457000 PM 1244 57500 1244 58000PM 1244 58500PM 1244 59000 PM 12 44 59 500 PM 124500178 PM 4 28 2011 4 28 2011 4 28 2011 4 28 2011 4 28 2011 4 28 2011 4 28 2011 4 28 2011 4 28 2011 4 28 2011 Time SSS m Right Temporalis RMS 06 amp 3 04 amp 02 0 7 1 1244 55178 12 44 56 000 12 44 56 500 PM 1244 57000PM 12 44 57500 12 44 58 000 1244 58500 12 44 59000 12 44 59 500 PM 12 45 00 178 PM 4 28 2011 4 28 2011 4 28 2011 4 28 2011 4 28 2011 4 28 2011 4 28 2011 4 28 2011 4 28 2011 4 28 2011 Time 1 Figure 37 RMS voltage signals TMJD Diagnostics System Senior Design Spring 2011 33 It can be seen from Figures 35 36 and 37 that the TMJD Diagnostics System is capable of acquiring accurate EMG data The system was tested over a period of six hours and the EMG data was consistent with short term tests To simplify the diagnosis for clinicians the raw EMG data is converted to tabular form to determine the number of bruxism events per muscle the total time spent bruxing and the exact times when the bruxing occurred These results are shown in FIG 38 for a test of two clenches
15. Project Timeline and kept the other team members up to date and organized expected completion dates for tasks in the project She also kept a running total budget for the team and separated items purchased using the Biomedical Engineering funds from items purchased by the UConn Health Center Kerry also established protocol for testing different electrode types for use in the final project and brainstormed several different electrode housing designs for the team to decide upon Kerry integrated the electrode snap leads into the Neuroband and sewed the device together Before the team decided that they were going to use a serial connection instead of a Bluetooth connection for sending data to the computer Kerry had designed and drew in SolidWorks a custom enclosure for housing the Bluetooth and circuitry TMJD Diagnostics System Senior Design Spring 2011 51 8 3 Mariana contribution to the project includes design and implementation of the LabVIEW program in charge of data acquisition storage and analysis learning to use the LabVIEW VISA functions doing research on methods to interface Bluetooth with the microprocessor doing research on different types of electrodes and helping with parts ordering For the data acquisition stage we were provided the code used for the completion of the Vital Signs Monitoring Project This code read the data sent to the computer via Bluetooth as a serial port and used the LabVIEW VISA functions I
16. Quantity Ext Price Usage Description IC DIP socket 8 0 94 4 3 76 Socket for pin AD620s IC DIP socket 1 63 1 1 63 Socket for 14 pin TLO74 Rocker DPST 6 26 1 6 26 Power switch switch DIN Female 1 63 1 1 63 DC input Transformer 86 58 1 86 58 Wall transformer Enclosure 7 20 1 7 20 Circuit Enclosure PCB 40 73 1 40 73 Printed Circuit Board TOTAL 181 97 Table 54 Budget breakdown for circuit components 8 TEAM MEMBERS CONTRIBUTION TO THE PROJECT 8 1 Michael Jorgensen My contribution to the project included research on electromyography research on biopotential amplifiers for EMG website construction maintenance electrode electrode lead purchasing touch proof connection design circuit design circuit construction microcontroller programming LabVIEW programming Bluetooth interface protoboard testing PCB design and testing enclosure construction and final product testing As part of my research I read numerous articles relating to electromyographic studies of temporomandibular joint disorder particularly those with reference to circuit electronics I referenced several books from the library including John Webster s Medical Instrumentation and Jeffrey Cram s Introduction to TMJD Diagnostics System Senior Design Spring 2011 49 Surface Electromyography which I used as a reference for much of the circuit design and electrode placement methods I shared the information obtained from my
17. The AD620 instrumentation amplifier datasheet is shown below TMJD Diagnostics System Senior Design Spring 2011 60 ANALOG DEVICES Low Cost Low Power Instrumentation Amplifier AD620 FEATURES EASY TO USE Gain Set with One External Resistor Gain Range 1 to 1000 Wide Power Supply Range 2 3 V to 18 V Higher Performance than Three Op Amp IA Designs Available in 8 Lead DIP and SOIC Packaging Low Power 1 3 mA max Supply Current EXCELLENT DC PERFORMANCE B GRADE 50 pV max Input Offset Voltage 0 6 max Input Offset Drift 1 0 nA max Input Bias Current 100 dB min Common Mode Rejection Ratio 10 LOW NOISE 9 nV Hz 1 kHz Input Voltage Noise 0 28 Noise 0 1 Hz to 10 Hz EXCELLENT AC SPECIFICATIONS 120 kHz Bandwidth G 100 15 Settling Time to 0 01 APPLICATIONS Weigh Scales ECG and Medical Instrumentation Transducer Interface Data Acquisition Systems Industrial Process Controls Battery Powered and Portable Equipment PRODUCT DESCRIPTION The AD620 is a low cost high accuracy instrumentation ampli fier that requires only one external resistor to set gains of 1 to 30 000 2 28 000 20 000 Ep csi SUPPLY CURRENT mA Figure 1 Three Op Amp IA Designs vs AD620 REV E Information furnished by Analog Devices is believed to be accurate and reliable However no responsibility is assumed by Analog Devices for its use nor for any infringemen
18. authors 2 1 2 12 Neuroband Data Acquisition Unit TMJD Diagnostics System Senior Design Spring 2011 28 The Neuroband device for housing the electrode snap leads was extensively modified to place snaps over the proper muscles The device houses 9 electrode snap leads two per muscle being analyzed and one on the forehead as a ground The attachment ends are all located on one side of the device to make the connection to the enclosure easy The prototype is fully adjustable to all head sizes The device is shown in FIG 31 Figure 31 Modified Neuroband device housing the snap electrode leads with lead ends coming out of one side 2 1 2 13 Computer The laptop Dell Latitude E6410 FIG 32 was decided upon by the University of Connecticut Health Center s IT department and is used to run the executable LabVIEW file The Dell E6410 is equipped with Windows 7 Intel Dual Core vPro 2 80 GHz processor 4 GB RAM 500 GB hard drive and a 14 1 inches Widescreen The computer receives the electromyographic data from the circuit via the National Instruments USB 6008 OEM Since the computer and the program will be running overnight saving and processing a large amount of data the 500 GB hard drive is optimal for this application TMJD Diagnostics System Senior Design Spring 2011 29 Figure 32 The Dell Latitude E6410 2 1 2 14 LabVIEW program An executable file contains a LabVIEW program that runs in the laptop It acquires the data th
19. by over 3 000 TMJD Diagnostics System Senior Design Spring 2011 47 Component Electrodes Electrode leads Circuit PCB Neuroband Components DAQ Laptop TOTAL Cost 36 33 192 45 117 51 40 73 80 00 169 00 1 200 00 1836 02 Table 53 Budget for final design The circuit components for each device are broken down in Table 53 Part R1 R2 R3 R7 R8 R9 R13 R14 R15 R19 R20 R21 D1 D2 D3 D4 D5 D6 D7 D8 D9 D10 D11 D12 D13 D14 D15 D16 R4 R10 R16 R22 C13 C14 C15 C16 C17 R5 R11 R17 R23 R6 R12 R18 R24 C1 C4 C7 C10 C2 C5 C8 C11 C3 C6 C9 C12 Value 100 kQ FDH333 Diode 1500 1 uF electrolytic 82 330 0 1 uF 1nF 0 1 uF TMJD Diagnostics System Price Each Quantity 5 12 5 0 32 16 5 4 5 5 5 4 5 4 5 4 5 4 5 4 Ext Price E Senior Design Spring 2011 Usage Description Impedance resistors to electrodes Patient protection circuitry Gain resistors for instrumentation amplifier Power bypass coupling capacitors Bandpass filter Bandpass filter Bandpass filter Bandpass filter Coupling capacitors 48 LED Green LED 5 0 11 1 5 0 11 Power indication LED R_LED 2200 5 1 5 A Current limiting resistor to LED U1 U2 U3 U4 AD620 7 06 4 28 24 Instrumentation Amplifier U5 TLO74 5 0 65 1 5 0 65 Bandpass filter op amp ADDITIONAL COMPONENTS Part Value Price Each
20. design proposed This design would make the computer unnecessary but available memory space for a long test like the one described will be difficult to find The memory would need to be wiped in between tests which may require the patient to do that him or herself if the test is to be repeated for several nights Then Alternative Design I was determined to be optimal for the convenience of the clinician and the patient The final product is a slight variation from Alternative Design 1 but does not vary much from its scope brief overview of the three alternative designs is presented below followed by a detailed description of the subunits that comprise the optimal design ALTERNATIVE DESIGN I The optimal proposed TMJD device will consist of two major parts a hat like data acquisition unit and a miniature laptop to acquire and display the data to the user TMJD Diagnostics System Senior Design Spring 2011 6 The hat device will house electrodes battery pack Bluetooth device and a series of filters and amplifiers in an integrated circuit The nine electrodes will be used to acquire signals from the left and right masseter and temporalis of the patient the four muscles associated with bruxing and clenching Two electrodes are needed for each muscle and an extra electrode will be used as a baseline set on the forehead of the patient The electrodes will be reusable to minimize the amount of setup done by the patient in home
21. device to the clinician who will be able to view the results by running the TMJD Results Application This application is also very user friendly At the start of this program the clinician will see the screen shown in Figure 45 The clinician will be able to select the files to view by clicking on TMJD Diagnostics System Senior Design Spring 2011 39 the path controls as indicated in Figure 45 View EMG Final 2 vi Right Masseter Left Masseter pue sr ee 4 University of Connecticut STOP Raw Data Signal Analysis Tabulated Results Left Masseter 0 5 0 25 Eo 3 57 7 00 00 000 PM 7 00 00 500 PM 7 00 01 000 PM 7 00 01 500 PM 7 00 02 000 PM 7 00 02 500 PM 7 00 03 000 PM 7 00 03 500 PM 7 00 04 000 PM 7 00 04 500 PM 7 00 05 000 PM 12 31 1903 12 31 1903 12 31 1903 12 31 1903 12 31 1903 12 31 1903 12 31 1903 12 31 1903 12 31 1903 12 31 1903 12 31 1903 Time litude 0 5 Right Masseter EJ 0 5 0 25 0 lt 0 25 2 5 7 7 00 00 000PM 7 00 00 500 7 00 01 000 7 00 01 500PM 7 00 02 000 7 00 02 500 7 00 03 000 7 00 03 500 7 00 04 000PM 7 00 04 500PM 7 00 05 000 12 31 1903 12 31 1903 12 31 1903 12 31 1903 12 31 1903 12 31 1903 12 31 1903 12 31 1903 12 31 1903 12 31 1903 12 31 1903 Time El mplitude Left Temporalis 1 7 00 00 000
22. noise from a reduced external component count The improved bandpass filter design is shown in FIG 22 Figure 22 Improved bandpass filter design offering 75 power reduction reduced external component count and improved signal quality due to reduced resistor thermal noise Protoboard testing of the improved bandpass filter design was conducted with a sinusoidal input and protocol similar to the above methods but is omitted from this report due to length considerations 2 1 2 7 60 Hz Notch Filter TMJD Diagnostics System Senior Design Spring 2011 22 filter is necessary to remove power line frequency and ambient noise at 60 Hz Since 60 Hz is within the bandwidth of electromyography signals a notch filter must be implemented to only attenuate frequencies in the 60 Hz range The notch filter is shown in Fig 23 9v D1 VW 1N4001GP T U1A OUTPUT R6 WA LM3900D 26 5kQ 26 5kQ 14 vDD T 0 2uF 9V 120 Vrms R8 60 Hz 100kQ 0 R7 13 2kQ c5 C6 0 1uF 0 1uF Figure 23 60 Hz notch filter This filter is a derivative of the Twin T notch filter design This was selected because it has a high Q factor and an infinitely deep notch The LM3900 from Texas Instruments was selected due to its excellent performance characteristics shown in Multisim 11 0 The AC simulation is shown in Fig 24 AC Analysis 400m Y 70m 40m Magnitude 7m 4m 1 4 7
23. op amp The gain equation was obtained from the AD620 datasheet and is given as _ 49 4 G 1 1 RG TMJD Diagnostics System Senior Design Spring 2011 16 Rearranging 49 4 Rg G 1 2 The amplification of the AD620 with a gain of 1000 is shown in Fig 13 Tek Trig d Pos 0 0005 SAVE REC Action About Saving Images Select Folder 1 Le atc cH Save TEKOO01 BMP CH1 5 00 M 10 0ms CH1 27 0 00 Current Folder is Figure 13 Amplification of the AD620 instrumentation amplifier with gain of 1000 This output was taken from a Tektronix TDS 2024B oscilloscope The output voltage was obtained from pin 6 of the AD620 following the coupling capacitor to remove the DC offset The input signal was a 200 Hz sinusoid waveform from a BK Precision 4011A function generator at a peak to peak voltage in the millivolt range Fig 11 shows that the AD620 amplifies the voltage to about 9 V where it becomes saturated Due to this saturation the gain of the instrumentation amplifier was reduced to 330 to maintain the linear operating mode of the IA The bandpass filler provides an additional amplification to the signal to ensure proper amplification 2 1 2 6 Bandpass filter 25 Hz 500 Hz The frequency range of EMG from facial muscles is approximately 25 Hz to 500 Hz Filters were implemented into the circuit in order to attenuate frequencies outside of this range
24. research with the team members to inform them of the current methods for electromyography I created the group website early and maintained it throughout both semesters This account included all updates document uploads and general maintenance issues The email allowed us to communicate effectively and have access to all important documents as well as providing Dr Litt with a means to view the information as well I contacted several companies regarding sample reusable electrodes so that our group could test them before committing to purchase them Of the companies I contacted In Vivo Metric supplied us with a donation of Ag AgCl reusable electrode I researched several disposable electrodes as well and confirmed that the Kendall Tyco ARBO electrodes were the best option for this project I designed and constructed the electromyography circuit throughout both semesters I learned the C programming language over winter break and in my microcontroller applications lab to effectively program the microcontroller in embedded C however this was removed from the project due to time constraints My theory behind circuit construction was to build one stage of the circuit at a time so that each could be tested separately and completely isolated from the other circuit stages For final circuit testing protocol the stages were connected and EMG signals were acquired from the temporalis and masseter muscles of a test subject I maintained the
25. the signals available on the I O connector are described in the USB 6008 6009 User Guide and Specifications document available for download at ni com manuals Table describes additional signals on the connector of the OEM devices Note The 2 5 V signal is not available on the USB 6008 6009 OEM device Table 1 Signal Descriptions LED Status LED Driver For more information about USB signals refer to the Universal Serial Bus Specification accessible at www usb org USB 6008 6009 OEM User Guide 4 TMJD Diagnostics System Senior Design Spring 2011 66 Using the 34 Pin Connector with a Board Mount Socket The USB 6008 6009 OEM device can be mounted to a motherboard using the 34 pin connector as shown in Figure 4 and Figure 5 1 Board Mount Socket 4 USB 6008 6009 OEM Device 2 34 Pin Connector 5 Mounting Standoff 3 Mounting Screws Figure 4 Mounting Using a 34 Pin Connector N Note Refer to the Device Components section for more information about mounting components Figure 5 USB Device Installed on Motherboard National Instruments Corporation 5 N USB 6008 6009 OEM User Guide TMJD Diagnostics System Senior Design Spring 2011 Connecting to USB You can use the USB connector on the USB 6008 6009 OEM device to connect to the USB host In this case leave the D and D signals on the 34 pin connector and VBUS unconnected If 5 V is needed supply it from the 34 pin connector You c
26. 11 4 27 2011 4 27 2011 4 27 2011 4 27 2011 4 27 2011 4 27 2011 4 27 2011 Time 3 E Figure 36 Electromyography data recorded from the TMJD Diagnostics System FIG 35 Displays the raw EMG signals acquired from the four facial muscles Per request of the client the raw data is plotted as voltage amplitude versus time The user may also view the signal analysis tab which displays the rectified FIG 36 and RMS voltage FIG 37 signals TMJD Diagnostics System Senior Design Spring 2011 32 cian View stop 4 University of Connecticut Patient View Cli Raw Data Signal Analysis Tabuiated Results Rectified RMS Right Masseter Rectified 15 i H 05 0 XE 1 1 1 1 1 1 D 12 44 13 810 12 44 14 500 12 44 15 000 12 44 15 500 12 44 16 000 12 44 16 500 12 44 17 000 12 44 17 500 12 44 18 000 12 44 18 810 PM 4 28 2011 4 28 2011 4 28 2011 4 28 2011 4 28 2011 4 28 2011 4 28 2011 4 28 2011 4 28 2011 4 28 2011 Time 4 l Left Masseter Rectified 08 3 06 04 2 0 7 T 1 1 T 1 T 1 0 12 44 13 811 12 44 14 500 12 44 15 000 12 44 15 500 12 44 16 000 12 44 16 500 124417000PM 12 44 17 500 124418000 12 44 18 811 PM 4 28 2011 4 28 2011 4 28 2011 4 28 2011 4 28 2011 4 28 2011 4 28 2011 4 28 2011 4 28 2011 4 28 2011 Time Right Temporalis Rectified
27. 8 V pk pk resulting in a gain of 0 488 Thus the bandpass filter sufficiently passed upper middle frequencies which is important because 450 Hz frequencies are at the upper end of the bandpass of EMG signals The attenuation at 450 Hz compared to 200 Hz is due to the fact that the cutoff of the filter is at 500 Hz so the filter begins attenuating frequencies just below 500 Hz Tek RI Trig d Pos 0 0006 SAVE REC Action Save Image Format BMP About Saving 2 Images Select Folder Save TEKOOOS BMP CH1 1 00 CH2 100 M500us CH1 Z 1 90 Current Folder is A N Figure 21 Bandpass filter at 1 kHz TMJD Diagnostics System Senior Design Spring 2011 21 It is evident from Fig 21 that bandpass filter sufficiently attenuated high frequencies as well The input signal was 5 04 V pk pk at 1 kHz The output signal was 760 mV pk pk resulting in gain of 0 151 This filtration was sufficient to meet our needs The cascaded highpass and lowpass filters were sufficient for filtration but they take up more space on the PCB and require additional components Additionally there was too much current consumption for the four quad amplifiers to be considered for battery applications Therefore the cascaded filters were substituted with a simpler bandpass filter that reduced power consumption by 75 Unexpectedly the new bandpass filter design actually improved the signal quality which is likely due to reduced thermal
28. D Diagnostics System Senior Design Spring 2011 35 TMJDiagnosticsTest_Final 1 1 vi gt Patient View Thresholds Clinician View University of Connecticut Instructions The Program Running LED will turn green indicating that the program is running In the Thresholds tab enter the values of threshold indicated by the clinician Stop the application by selecting the STOP button located in the upper middle of the screen For additional help select the HELP button located in the upper middle of the screen or consult your user manual Program Running 6 m s 2 Internet E TMUDiagnostic Search Desktop 94 Figure 40 TMJD Diagnostics Application Showing instructions and light indicating the program is running TAJDiagnosticsTest_Final 1 1 vi gt Patient View Thresholds Clinician View University of Connecticut Instructio The Pro 17 the Thresholds tab enter the threshold valuesindicated by the dinician The program wil start the data acquisition P To stop the application slect the STOP button located in the the T upper middle of the screen The data from the session wil be automatically saved For additional help and troubleshooting topics please consult Stop the the user manual the For addi Cx upper middle of the screen or c
29. Final Report Temporomandibular Joint Disorder Diagnostics Device Michael Jorgensen Mariana Hu Kerry Semle Team 5 Client Dr Mark Litt Ph D University of Connecticut Health Center 263 Farmington Avenue Farmington CT 860 679 4680 TABLE CONTENTS hcc 2 IB anus insana 2 13 Background a l e ead da cT Aide eee iat 2 1 2 Purpose of the ana qa al cases ceases enne ren nnne enn enne s 2 1 3Previous Work Done by Others ene ennemi nn tnn 3 1 3 1 eee esee reet 3 1 3 2 Patent Search 6 1 4 for Rest of the Report ener enne enn 6 PA ivo uod DI AI OPTED REP EE 6 Alternative oae nds tap Da ceo ond Deest 6 2 10ptimal 620 eene nnnm tentent nennen 10 2 1 10bJ ctiVe RERO E RO ra do aA 10 2 22 SU DU 11 22 Prototype 31 Realistic ett tenis 43 A Safety ISSUES iiaiai ANE NNNNA ENE 44 5 Impact of Engineering Solutions dre eate rcp POR ere t eo 46 6 Lit
30. J 24 15 Tos 05 07 T D 7 1 1 i 1 T i 12 44 13 807 12 44 14 500 124415000PM 12 44 15 500 124416000 12 44 16 500 PM 12 44 17 000 12 44 17 500 12 44 18 000 PM 124418807 PM 4 28 2011 4 28 2011 4 28 2011 4 28 2011 4 28 2011 4 28 2011 4 28 2011 4 28 2011 4 28 2011 4 28 2011 Time a ms Left Temporalis Rectified 154 05 1 T T U 7 i 12 44 13 807 PM 12 44 14 500 PM 12 44 15 000 12 44 15 500 12 44 16 000 12 44 16 500 PM 12 44 17 000 12 44 17 500 12 44 18 000 PM 124418807 4 28 2011 4 28 2011 4 28 2011 4 28 2011 4 28 2011 4 28 2011 4 28 2011 4 28 2011 4 28 2011 4 28 2011 Time J n I Figure 36 Rectified EM G signals 4 University of Connecticut Patient View Clinician View Raw Data Signal Analysis Tabulated Results Rectified RMS Left Masseter RMS ad 124455182PM 124456000 1244 56500 1244 57000 12 44 57 500 PM 1244 58000 PM 12 44 58 500 PM 1244 59000PM 12 44 59 500 PM 124500182 PM 4 28 2011 4 28 2011 4 28 2011 4 28 2011 4 28 2011 4 28 2011 4 28 2011 4 28 2011 4 28 2011 4 28 2011 Time 2 Right Masseter RMS T 1 0 n 1 0 1 1 0 1 1 12 44 55 179 12 44 56 000 PM 12 44 56 500 PM 12 44 57 000 12 44 57 500 PM 12 44 58 000 PM 12 44 58 500 PM 12 44 59 000 12 44 59 500 PM 12 45 00 179 4 28 2011 4 28 2011
31. PM 7 00 00 500 PM 7 00 01 000 PM 7 00 01 500 PM 7 00 02 000 PM 7 00 02 500 PM 7 00 03 000 PM 7 00 03 500 PM 7 00 04 000 PM 7 00 04 500 PM 7 00 05 000 PM D gt I w Figure 45 TMJD Results Application showing path controls displays for the four muscles and the tabs for selecting Raw Data Signal Analysis or Tabulated results TMJD Diagnostics System Senior Design Spring 2011 40 View Final 2 vi Right Masseter Left Masseter Ap e U Jap University of Connecticut Raw Data Signal Analysis Tabulated Results Left Masseter Look in C Local Disk osem 3 sonata threshold T ium 5 Latitude E6410 resholdRM My Recent E Documents and Settings E thresholdRM lum Documents One 18 thresholdaT C LabvIEw Runtime Engine 2010 E threshold Ed Thu Apr 28 2011 Left Masseter Imv y L 7 00 00 500 PM 7 00 01 00 l 7 00 04 000 PM 7 00 04 500 PM 7 00 05 000 PM 12 31 1903 12 31 1903 12 31 19 me 12 31 1903 12 31 1903 12 31 1903 3 2 E Packages E Thu Apr 28 2011 Right Temporalis mv 3 Right Masseter Program Files TradkitAudit id 0 5 Qwinoows done txt 4 az 8 threshold 0 i ES thresholdLM Ium H 0 25 Ed threshold T 0 5 1 7 00 00 000 7 00 00 500 7 00 01 00 7 00 04 000PM 7 00 04 500 7 00 05 000 12 31 1903 12 31
32. The electrodes RC filtering diode protection and amplification circuitry is shown in Figure 2 The 1N4001 diodes will be replaced by FDH333 low leakage diodes in the physical to ensure that no current is transferred to the patient Multisim does not have a library consisting of FDH333 diodes Additionally a 1N4001 diode will be added to each diode at the positive terminal of each op amp to ensure maximal protection of the power supply circuit This limits the damages that may be caused if the user inserts the batteries backwards Two nine volt batteries will power the electrical devices The power supply circuit is shown in Figure 1a and its simulation is shown in Figure 1b It is evident that the dual power supply can provide 9 V and 9V for a total of 18 V A dual power supply is necessary to power the AD620 instrumentation amplifier The two 22 pF tantalum capacitors stabilize the current The filters and amplifiers will receive signals sent by the electrodes They will filter out ambient and artifact noise and amplify the signal so that it can be transmitted via Bluetooth to the laptop First order RC filters will be coupled directly to the electrodes and active filters will follow each instrumentation amplifier The lowpass active filter circuitry is shown in Figure 3a along with its AC analysis in Figure 3b The passband drops sharply at 500 Hz indicating that the filter has been designed properly The phase shift shown in Figure 3b will
33. This will likely be sufficient to meet EMG filtering standards as the environment in which our product will be used will likely not have a significant amount of electromagnetic interference EMI and therefore digital filtration in LabVIEW is an acceptable means for filtration 2 1 2 8 Microprocessor If a microprocessor is used in future applications it should be responsible for acquiring four muscle signals post amplification and filtration performing analog to digital conversion on the signals multiplexing the four signals into one output and then passing the data to a Bluetooth module by means of RX and TX The microcontroller was attempted but was substituted due to time constraints A description of the microcontroller progress will be discussed herein TMJD Diagnostics System Senior Design Spring 2011 24 ATMega644PA microcontroller from was selected for use in this project It is an 8 bit microcontroller with 64 Kbytes of Flash memory 8 channels of 10 bit A D single ended channels all of which satisfy the requirements of the project The ATMega644PA is shown in FIG 26 Figure 26 ATMega644PA microcontroller Some code was written to perform analog to digital conversion ADC of the EMG signals well as inform the user of low battery status both of which functioned correctly and are available for viewing in the Appendix of this report The function ReadADC was used to convert the analog EMG signals to digital s
34. a common symptom of TMJD that clinicians use to diagnose it Currently patients who are suspected to have TMJD or exhibit signs of bruxism through wear on the teeth are subject to spend a night in a sleep lab in which they are connected to electrodes while sleeping Those electrodes are connected to machines through wires that record and analyze the activity of the masseter and temporalis A trip to the sleep lab is inconvenient for many patients many of whom also have sleep apnea and typically use a breathing machine 1 2 Purpose of the Project The TMJD Diagnostics Device aims to make sleep labs for TMJD diagnosis superfluous It will make it possible for the muscular activity associated with TMJD Diagnostics System Senior Design Spring 2011 2 bruxing to be recorded in the patient s home This would take the necessity of transporting a breathing machine out of the diagnosis of TMJD for patients with sleep apnea and be more cost effective for patients as well as their insurance companies 1 3 Previous Work Done by Others 1 3 1 Products A current low cost bruxism diagnostic device is in the market The BiteStrip is a single use disposable device used by the patients at home It is a miniature electronic system consisting of two pre gelled skin EMG electrodes and an EMG amplifier for acquiring nocturnal EMG signals from the mastication muscles a CPU for running real time software that analyzes EMG strength patterns and for detecting a
35. an also use a USB connector on your motherboard to connect the USB 6008 6009 OEM device to the USB host through the 34 pin connector In this case do not connect to the USB connector on the USB 6008 6009 OEM device Using the Status LED Driver TheLED signal indicates the device status as described in Table 2 An open collector driver drives the LED signal For applications that use the LED signal connect a 4 7 kQ resistor from the LED signal to the 5 V signal Table 2 Device Status LED Signal Behavior USB device enumerated configured and not Square wave with frequency of 2 Hz suspended USB device is not enumerated not configured Not driven pulled up or is suspended Two possible uses of the LED signal are as follows Todrive an LED to give a visual indication that the device is active To drive a watchdog timer circuit that monitors the device state Electrical Characteristics Table 3 lists the LED electrical characteristics Table 3 Electrical Characteristics USB 6008 6009 OEM User Guide 6 ni com TMJD Diagnostics System Senior Design Spring 2011 68 Device Components Table 4 lists the components used for interfacing and interacting with the USB 6008 6009 OEM device Table 4 NI USB 6008 6009 Device Components Reference Designator s Manufacturer Component Part Number USB cable 2 m 34 pin mating connector or equivalent 745798 01 female to female 14 mm long Mounting St
36. and filter the electrical signals obtained from the facial muscles The electromyography EMG circuit can be visualized by means of a flowchart created using Microsoft Visio 2010 as shown in Fig 5 Protection Instrumentation Bandpass Filter Wu J Circuitry Amplifier 25 Hz 500 Hz Analysis w LabVIEW USB 6008 Storage and Notebook PC J Program DAQ lt Display Figure 5 Electromyography circuit flowchart The components of Fig 5 will be discussed herein 2 1 2 2 Power Supply The circuit operates from a 12 V 12 V 5 V AC DC wall transformer 12 V was necessary to provide sufficient voltage to the operational amplifiers op amps Future applications should employ a DC DC converter with a switching inverting regulator with buck boost capabilities to convert the positive voltage supply to that of opposite polarity This was not included in the final product due to a relatively late change in design that did not allow for additional circuit design The power supply circuitry is shown in Fig 6 TMJD Diagnostics System Senior Design Spring 2011 11 2 63 GJ e I Figure 6 Power supply simulation using Multisim 11 0 The power supply circuit provides 12 V to the op amps This was verified by protoboard testing using a BK Precision 1760A DC Power Supply and a Fluke 8808A 5 1 2 digital multimeter In Alternative Design 1 the power supply consisted of two 9 V b
37. andoff 3 16 in HEX female to female 1 4 in long To order contact NI National Instruments Corporation 7 NI USB 6008 6009 OEM User Guide TMJD Diagnostics System Senior Design Spring 2011 69 USB 6008 6009 OEM Device Specifications Most specifications of the USB 6008 6009 OEM device are listed in the USB 6008 6009 User Guide and Specifications document on ni com manuals The following sections contain exceptions to the main specifications External Voltage hy Note 2 5 V output is not available Physical Characteristics 8 76 cm x 5 72 cm x 1 55 cm 3 45 in x 2 25 in x 0 610 in IA 7 UU 4 wall header part number N2534 6002RB USB 6008 6009 OEM User Guide 8 ni com TMJD Diagnostics System Senior Design Spring 2011 70 Where to Go for Support The National Instruments Web site is your complete resource for technical support At ni com support you have access to everything from troubleshooting and application development self help resources to email and phone assistance from NI Application Engineers National Instruments corporate headquarters is located at 11500 North Mopac Expressway Austin Texas 78759 3504 National Instruments also has offices located around the world to help address your support needs For telephone support in the United States create your service request at ni com support and follow the calling instructions or dia
38. atteries to provide an operating voltage range of 9 V Testing methods were implemented in order to determine the battery life of the device which must be at least 12 hours to accommodate for one night of sleep A voltage level indicator was coded in embedded C to inform the user of battery life A warning LED emitted when the battery life was below 12 hours as well as a warning message in the LabVIEW program to inform the user of low battery The code for the battery level indicator and other microcontroller functions are included in the Appendix of this report It should be noted that the code may not compile due to formatting issues with this report 2 1 2 3 Electrodes Electrical potentials from the four muscles of mastication were be acquired from nine Ag AgCl surface electrodes Each muscle requires two electrodes one electrode for positive and one electrode for negative An additional electrode must be used as a reference electrode to provide adequate grounding Reusable electrodes were initially considered because they improve the comfort and simplicity of the device They can potentially be removable from the device so that the fabric may be washed and they can also be easily replaced if they TMJD Diagnostics System Senior Design Spring 2011 12 fail The first consideration for reusable electrode was the E272 LS SLIM TRODE manufactured by In Vivo Metric Healdsburg CA shown in FIG 7 e Figure 7 In Vivo Me
39. ature lightweight film similar to the one of BiteStrip The device will be self adhesive to be placed by the patient over the Masseter and Temporalis muscles before going to sleep As in the previous design a program contained in a LabVIEW executable file will be used for collecting data and performing corresponding analysis and display of relevant information to the clinician The integration of the elements into a miniature film would avoid exposure of wires and circuit components to the user The small size and the light weight of the device would also provide major comfort to the patient during sleep However since ideally the clinician would require collection of electromyography signals from the four muscles the cost of the device would increase significantly since four Bluetooth modules would be needed for this design This design maintains the advantage of wireless data transfer to the computer presented in Alternative Design 1 while introducing an alternative to the mechanical design of the device that seems to provide comfort to the patient However four identical devices would be required for a more accurate and complete diagnosis This translates into a significant increase in the cost for this TMJD Diagnostics System Senior Design Spring 2011 8 design On the other hand the Alternative Design 1 uses the same modality of data acquisition transfer and analysis but at lower cost Moreover it introduces a unique hat design Due to t
40. chanism for the Effectiveness of Splint Therapy Journal of Oral Rehabilitation 34 2007 97 104 Print Galaros Alan G Karen Williams and Leonard Lausten Diurinal Variation in Pain TMJD Diagnostics System Senior Design Spring 2011 53 Reports in Temporomandibular Disorder Patients and Control Subjects Journal of Orofacial Pain 22 2 2008 115 21 Print Gallo Luigi M Gilles Lavigne Pierre Rompre and Sandro Palla Reliability of Scoring EMG Orofacial Events Polysymnography Compared with Ambulatory Recordings European Sleep Research Society 6 1997 259 63 Print Kato Takafumi Norman M Thie Jacques Y Montplaisir and Gilles J Lavigne Bruxism and Orofacial Movements During Sleep Dental Clinics of North America 45 4 2001 657 84 Print Philips Semiconductor UART to Bluetooth Interfacing NXP Semiconductors Philips 43 Kraus Steven Temporomandibular Disorders 2nd ed New York NY Churchill Livingstone Inc 1994 Print Robertson Gordon Electromyography Processing University of Ottawa 05 11 2007 Web Apr 2011 www health uottawa ca biomech courses apa4311 emg p2 pps Webster John Medical Instrumentation Application and Design 2nd ed Boston MA Houghton Mifflin Company 1992 Print 11 ACKNOWLEDGEMENTS We would like to thank the following people for their contribution to our project Dr Mark Litt Ph D Dr John Enderle Ph D Emily Jacobs Marek Wartenberg Sonia Hel
41. device to liquids or flammable materials Some improvements to the enclosure may include aluminum or steel casing however these were avoided due to the ease of manufacturing with a plastic enclosure I designed and programed the LabVIEW program to acquire the EMG signals as well as write the data to a LabVIEW measurement file My program interfaced with Mariana s program so that the data could be read in by a second VI Additionally I took a major role in final product testing With real time EMG data acquisition I was able to alter the LabVIEW code accordingly to present the user with the most accurate results and intuitive graphical user interface Overall I was very satisfied by the progress of the project and the cooperation and effort by my team members It is rewarding to witness the final product and it is my hope that this device will continued to be manufactured and used to help temporomandibular joint disorder patients in the United States and around the world 8 2 Kerry Semle Kerry s contributions to the project were primarily organizational and aid related Kerry organized and saved all literature used on the project to a Google Documents account The Google Documents account gave the team a place to save documents so that they could all access them These documents included reports presentations literature the project timeline the total budget spreadsheet and individual purchase orders Kerry managed the Microsoft
42. e NATIONAL INSTRUMENTS TMJD Diagnostics System Senior Design Spring 2011 63 Figure 2 shows the USB 6008 6009 OEM device dimensions 0 650 16 51 6 0 125 3 18 s 2 725 69 22 2 305 58 55 3 300 83 82 PIN 1 0 450 11 66 0 344 8 74 PIN2 0 119 3 0 000 295 20 150 3 81 212 20 575 714 61 I nu 0 725 18 42 a de ok 1 645 41 78 1 300 33 02 1 025 26 04 0 887 22 53 0 413 10 49 0 275 6 99 0 000 0 00 70 150 3 81 1 775 45 09 0 475 12 07 0 345 8 76 4 1 0 5059 0 546 13 11 0 433 11 00 r 0 063 1 60 0 000 0 00 i lt 2 250 57 15 _ 004 209 Figure 2 USB 6008 6009 Device Dimensions in Inches Millimeters USB 6008 6009 User Guide 2 TMJD Diagnostics System Senior Design Spring 2011 1 0 Connector Figure 3 shows the USB 6008 6009 OEM device I O connector pinout signal names are shown in single ended mode Differential mode signal names are in parentheses AI GND Al 0 Al 0 Al 1 Al 1 Al 2 Al 2 Al 3 Al 3 Al GND 0 Figure 3 USB 6008 6009 Terminal Assignments National Instruments Corporation 3 NI USB 6008 6009 OEM User Guide TMJD Diagnostics System Senior Design Spring 2011 65 Signal Descriptions Most of
43. e 1 BatteryLevelIndicator SignalMultiplexer OCR B sig1 1 OCROA41 128 1 Duty cycle 0 to 100 12 3 Bluetooth Connection Main Code in Embedded C include lt stdlib h gt standard include files include lt pic h gt include lt htc h gt CONFIG DUNPROT amp PWRTDIS amp amp WDTDIS amp BORDIS amp LVPDIS ifndef _XTAL_FREQ Unless already defined assume 4MHz system frequency This definition is required to calibrate _ delay us and _ delay ms define _XTAL_FREQ 7372800 endif TMJD Diagnostics System Senior Design Spring 2011 58 void InitLCD void void DisplayC unsigned char position const char str void DisplayCharacter unsigned char pos unsigned char c void clear_display void void InitSerial void void SerialString const char str void SerialCharacter unsigned char c char SerialReception void int Speed This subroutine performs all initializations of variables and registers void Initial void ADCS80 1 Use A D FOSC 8 ADCON1 0x44 Select PORTA pins for ADC or digital 1 0 TRISA 0x0B Set I O for PORTA TRISB 1 Set 0 for PORTB TRISC 0xB7 Set I O for PORTC TRISD 0 00 Set I O for PORTD TRISE 0 04 Set I O for PORTE PORTD 9 Turn off LEDs OPTION 0b00000100 Timer 0 prescale set 32 1 Nigh INTCON 0611100000 Enable Timer 0 interrupts InitLCD InitSerial void ADConvert v
44. e 51 Electrical shock to patient Courtesy of National AG Safety Database Electrical current in the hundreds of milliampere range may result in cardiac arrhythmias that degenerate into ventricular fibrillation and ultimately death It is crucial that the patient is protected against any possibility of an electrical shock A parallel diode configuration has been implemented into the design as shown in Fig 9 to limit the voltage in contact with the user to 700 mV The electrode potentials will likely never reach anywhere near this level however it is of vital importance to protect the patient regardless Additionally the wall transformer isolates the patient to ensure that there is no galvanic connection between the patient and the wall The only possible current that could pass through to the patient is DC which is not nearly as hazardous as AC current The possibility of this event occurring is nearly impossible however in the event of electric shock the user should disconnect the power cable from the circuit enclosure immediately There may be a biological hazard as a result of the electrode skin interaction Some patients may be allergic to Ag AgCl silver silver chloride electrodes and may potentially have adverse reactions A life threatening anaphylaxis is unlikely however skin irritation may persist on the areas where the electrodes are connected The Kendall Tyco ARBO disposable electrodes are latex free and throughout extensive test
45. e long Eearning aire ge reperi den eren rene ree 47 F BUGS 47 8 Team Members Contribution to the cess nn 49 n red 49 3 2 Kerry oo RE 51 9 9 HU ene nee on He RAE 52 9 Conclusion acini nde toa ie Bie in vete reete eem te eee 52 10 References cete Ia Pe tek iere ire ed rer ard inc deat ei ee Tn dnd 53 Ti Acknowledgeiments o ea 53 IZAppendix 4e ce G e Qa asa need temp ria su Nawa puas a dett as as 54 12 1 Updated Specifications sow on Fre e ton bn rr brit 54 12 2 Microcontroller Code in Embedded C 55 12 3 Bluetooth Connection Main Code in Embedded C sss 58 12 4 Bluetooth Serial Connection Code in Embedded C 60 12 5 Datash C6ts cercano A EUR e tree sm qasa Trudi 60 TMJD Diagnostics System Senior Design Spring 2011 ABSTRACT The purpose of this project is to develop a wearable device to record bruxism tooth grinding and clenching events and joint sounds during sleep Diagnostic screening of bruxism is currently conducted in sleep labs through the use of electromyography EMG EMG re
46. el offers a low cost alternative to data acquisition and USB interfaces to embedded designs For the final product it is contained within the circuit enclosure for ease of use for the patient The USB 6008 was tested extensively and it acquires data similar to higher model PXI DAQ devices and completely satisfied the data acquisition requirements for the project 2 1 2 10 Protoboard testing The test setup is shown in Fig 28 TMJD Diagnostics System Senior Design Spring 2011 26 36 Tm 1011 gm t assi A m Figure 28 Protoboard test setup Power was supplied to the circuit via a BK Precision 1760A DC power supply A BK Precision 4011A 5MHz function generator was used to generate the sinusoidal input waveforms A Tektronix TDS 2024B Four Channel digital storage oscilloscope was used to capture the input and output signals A Fluke 8808A digital multimeter was used to test voltage and current levels throughout the circuit 2 1 2 11 Bluetooth Bluetooth is a wireless technology standard and was initially selected as the communication protocol of choice Bluetooth allows for a wireless interface significantly reducing the complexity of the device and making it user friendly for set up and maintenance Bluetooth modules can generally be powered from low voltage supplies and work excellent when powered by battery The range can be anywhere up to 350 feet or more which is desirable since
47. ena Contreras Ortiz Dave Kaputa Antonio Costa Penny Dobbins Kerrie Wenzler Jennifer Desrosiers These individuals were instrumental in the development of the TMJD Diagnostics System 12 APPENDIX 12 1 Updated Specifications TMJD Diagnostics System Senior Design Spring 2011 54 The circuitry underwent several revisions throughout both semesters and will be described herein Initially RC lowpass and highpass filters were implemented into the design to provide a first order filtering of the non amplified EMG signals These were removed per request of Dr John Enderle due to the fact that they would filter out frequencies in the bandwidth This was tested on the protoboard and they did not provide sufficient filtering characteristics Thus they were been removed from the final design Secondly the 60 Hz notch filter was initially designed to remove 60 Hz frequencies utilizing a Twin T filter with a high Q factor The filter was tested with physical components and the results were that of severe distortion of the EMG signal Due to the fact that the device will not be used in an environment of high electromagnetic interference it was removed from the final product design A Bluetooth connection was described as the optimal design for this project and it still stands to offer many benefits over the final product This was removed from the project due to time constraints with microcontroller programming data encryption auto play script
48. ew Clinician View s 4 University of Connecticut Raw Date Signal Analysis Tabulated Results Left Masseter 05 025 8 9 025 05 1 7 40 02 970 PM 74003500PM 740 4000 7 40 04500 74005000 7 40 05 500 7 40 06000 740 06500PM 7 40 07000 17 4007500 7 4 07970 PM 4 27 2011 4 27 2011 4 27 2011 4 27 2011 4 27 2011 4 27 2011 4 27 2011 4 27 2011 4 27 2011 4 27 2011 4 21 2011 Time Right Masseter 4 0 5 0 25 0 0 25 0 5 7 40 02970 PM 7 4003 50 740 04000 7 40 04 500 PM 74005000 7400550 740 06000 74006500PM 74007000PM 74007500 740 07970 4 21 2011 4 21 2011 4 21 2011 4 21 2011 4 21 2011 4 21 2011 4 21 2011 4 21 2011 4 21 2011 4 21 2011 4 1 2011 Time J j Amplitude Left Temporalis ii 0 35 5 o 5 Amplitude 0 74002968 PM 74003500PM 74004000PM 7400450 74005000PM 74005500PM 7 40 06 000 74006500PM 740 07000PM 74007500PM 75007968 PM 4 27 2011 4 27 2011 4 27 2011 4 27 2011 4 21 2011 4 27 2011 4 21 2011 4 21 2011 4 27 2011 4 27 2011 aon Time Right Temporalis a 05 Amplitude 5 d 1 7 40 02 968 PM 7 40 03 500 7 40 04 000 7 40 04 500 7 40 05 000 7 40 05 500 7 40 06 000 7 40 06 500 7 40 07 000 PM 7 40 07 500 PM 7 40 07 968 PM 4 27 2011 4 21 2011 4 27 2011 4 27 20
49. ey are entirely protected from electric shock 2 1 2 5 Instrumentation Amplifier TMJD Diagnostics System Senior Design Spring 2011 15 biopotential amplifier has several requirements including high input impedance typically gt 10 GQ low output impedance and a high CMRR typically gt 100 dB A three op amp instrumentation amplifier encompasses all of these parameters and was selected as the optimal amplifier design The AD620 instrumentation amplifier IA from Analog Devices was selected because it is a low cost high accuracy instrumentation amplifier with gains from 1 to 10 000 set by one external resistor Its low noise low input bias current and low power makes it ideal for medical applications such as electromyography Its low power also makes it well suited for battery operation The instrumentation amplification circuitry is shown in Fig 12 PatientProtection lt lt Vout gt gt PatientProtection lt VDD Figure 12 Instrumentation amplifier utilizing the AD620 The op amp is configured as a differential amplifier to amplify only the difference between the positive and negative electrodes 1N4001 diode is placed in series with the components positive power supply to ensure maximal protection of the op amp This will eliminate the possibility of reversing the power supply potentially damaging the component A gain of 330 was selected using a resistor of 150 Q connected between pins 1 and 8 of the
50. have a slight effect on signal but will not distort the amplitude The highpass active filter circuitry is shown in Figure 4a along with its AC analysis in Figure 4b Once again the passband to stopband transition is steep indicating that the filter will perform sufficiently The phase shift shown in Figure 4b will likewise slightly effect the signal but will have no effect on the amplitude The 60 Hz notch filter is shown in Figure 5a along with its AC simulation in Figure 5b This filter is based on the Twin T design which provides a high Q and deep notch suppressing only frequencies in the 60 Hz range The lowpass and highpass active filters were designed with FilterLab software to quickly design fourth order Butterworth filters whereas the 60 Hz notch filter was designed from previous knowledge of the Twin T notch filter The miniature laptop will be Bluetooth enabled and will be equipped with an executable file designed in LabVIEW This executable file will acquire data and save important events as well as convert the hertz units to Newtons to make the data something tangible for the clinician The program will be setup so that the patient simply has to turn on the laptop and press start on the program for it to start recording The program will automatically save the necessary data and process it so that it will be usable for the clinician once the laptop is brought back to them The steps to activate the device are displayed in Figure 6
51. his the Alternative Design 2 is not considered the optimum for now ALTERNATIVE DESIGN III An electromyography circuit will be secured into the hat design and positioned superior to the patient s head similar to Alternative Design 1 Positioning the circuit on top of the patients head eliminates the possibility that the patient will damage the circuit during sleep This placement also improves the comfort of the device as the patient will never lean on the circuit The circuit will acquire signals from nine electrodes placed over the muscles of mastication provide protection to the patient and the components filter data outside of the EMG bandwidth and amplify the signals to a desired level The circuit is similar to alternative design 1 however the communication protocol and memory storage is altered to reduce the final product cost Once the data is processed and amplified by the AD620 instrumentation amplifier it will be sent to a memory storage component in the circuit When the user has finished recording the data will be loaded onto a computer equipped with LabVIEW via serial RS 232 communication protocol To avoid the necessity of the computer having a license for LabVIEW software an executable file of the program will be stored on an accompanying CD ROM The user will simply connect a serial cable to the device and to the computer and the data will be automatically transferred to a LabVIEW measurement file The LabVIEW program w
52. ignals for the microcontroller The function BatteryLevelIndicator was used to alert the user when the battery was low This indicator was designed to work with a Red Green LED so that when the battery power was sufficient to power the device a green color would be emitted low battery emitted a yellow color and immediate replacement yielded a red color A red color indicates that the device will not last much longer Time division multiplexing was selected to combine the four EMG signals into one output Time division multiplexing TDM is a type of digital in which two or more bit streams are transferred apparently simultaneously as sub channels in one communication channel but are physically taking turns on the channel The function SignalMultiplexer in this appendix was the preliminary method to multiplex signals Shift registers may also be considered in future applications TMJD Diagnostics System Senior Design Spring 2011 25 2 1 2 9 Data Acquisition To acquire data from the circuit and perform analog to digital conversion the USB 6008 OEM from National Instruments was selected It has 12 bit analog input resolution of 12 bits and has a maximum sampling rate of 10 kS s both of which satisfy the criteria of this project Its maximum voltage range and minimum voltage accuracy are also suitable for EMG signal acquisition The USB 6008 OEM is shown in FIG 27 Figure 27 USB 6008 OEM DAQ from National Instruments The OEM mod
53. ill be simple and easy to use The clinician will load the executable file onto a computer of their choice and run the program A serial port will then connect the device to the computer and data transfer will commence Once the data has been loaded onto the clinician s computer additional processing will be implemented to present useful diagnostic information This may include the total time spent bruxing the total number of bruxing events the time at which bruxism occurred and the maximum force and pressure during bruxism This alternative design eliminates the necessity for a notebook computer which reduces the cost by nearly 70 This cost reduction is incredibly desirable but memory availability becomes an issue Since data will be sent to a memory chip overnight eight or more hours of data could be stored It may not be possible to store this amount of information onto one memory chip Additional memory chips may need to be implemented and entire memory wipes may need to be used each time the device is powered on The transfer of data may also become an issue as there would be no way to check if the data displayed in the LabVIEW program is valid or if it were corrupted or overwritten in the storage or transfer process A direct link to the LabVIEW program as described in the first alternative design is the most desirable method per request of the client The exact time at which bruxing TMJD Diagnostics System Senior Design Spring 2011 9
54. ing the patient stops the data acquisition by clicking the Stop button located in the upper middle of the screen A summary of the results can be viewed under the Tabulated results tab shown in Figure 44 showing total number of bruxing events of each muscle total duration of the events and the exact times of these events TMJD Diagnostics System Senior Design Spring 2011 38 View EMG Final 2 vi FS u Raw Data Signal Analysis Tabulated Results s MASSETER CLENCH TIME minutes Right Masseter 2 Right Masseter Right Temporalis Bruxism Events Displays the total amount of time 05151 0 22 4 spent clenching Left M t in minutes Left Masseter Left Temporalis e asseter 0 00 0 22 Bruxism Events il TEMPORALIS EVENT TIMES Right Temporalis Right Temporais Left Masseter Right Masseter Left Temporais Records th t gt Bruxism Events bruxism event 9 pezam 9 F z 7 ees O times The user esas o ZEEN 4 can scroll through EZEIZ ft T r li the event times 5 45 35 Pm 4 36PM sisse Pm z emporalls using the arrows Events 5 Hotmail mariana_md Document Microsof LabVIEW 10 0 Figure 44 Signal Analysis tab of the TMJD Results Application showing rectified signals of the four muscles The patient will return the TMJD Diagnostics
55. ing did not cause any adverse reactions TMJD Diagnostics System Senior Design Spring 2011 45 Clinical trials should conducted prior to release into the market Institutional Review Board IRB was been drafted by our client Dr Mark Litt Ph D and is currently in the process of approval During clinical trials it is of utmost importance to ensure the safety of the volunteers One member of the group Mike has been certified by the Collaborative Institutional Training Initiative CITI to perform clinical trials at the Storrs campus Dr Litt can likewise conduct trials at the UConn Health Center Another safety issue is that of sanitation between uses The final product is machine washable and the circuitry and electrode electrode lead components are easily removable The device is capable of being disassembled and reassembled by users who have been informally trained The hat design of the project accommodates for this safety issue 5 IMPACT OF ENGINEERING SOLUTIONS If the proposed device were to be successful and widely accepted by the dentistry community it may change the industry First the device would be more convenient and economical for the patient than staying overnight in a sleep lab Fig 52 The patient would no longer be required to sleep outside of the comforts of his or her home for the diagnosis of TMJD This device will be much cheaper for insurance companies than the traditional sleep labs since there is no
56. ize void InitADC void voltage important TCCROA TCCROB TCCROA TCCR B 1 1 lt lt WGM 2 1 1 lt lt CS01 clk 8 OCR A 62 5 set frequency at 16kHz with clk 8MHz and CS 1 TMJD Diagnostics System Senior Design Spring 2011 56 OCR B ADCH 1 OCR A 1 128 1 set the duty cycle TIMSKO 1 lt lt OCIE0B 1 lt lt enable COMPB and OVF interruptions EE sb eb RE eb oe FOE E Ob Io EIE Battery level indicator designed for use with a bi color LED Green Red ope oe ae ee ee ope ae ae AE ee J void BatteryLevelIndicator void DDRD data ReadADC 0 Vin 100 data 5 001 1023 decimal Vin 100 wholeVin Vin 100 0x30 Whole number voltage tenth_decimal 1 10 0 30 Tenths place decimal if wholeVin gt x35 Greater that or equal to 5 0 V Green PORTD OXFB if wholeVin gt 0x34 amp amp wholeVin 0x35 if tenth_decimal gt 0x39 Greater than or equal to 4 9 V GREEN PORTD 0xFB if tenth_decimal lt 0x39 amp amp tenth_decimal gt 0x35 Range 4 5 V 4 9 V YELLOW if tenth_decimal lt x35 Less than 4 5 V RED PORTD OXF7 if wholeVin lt 0x34 PORTD 0xF7 eoe opo ke
57. l 512 795 8248 For telephone support outside the United States contact your local branch office Australia 1800 300 800 Austria 43 0 662 45 79 90 0 Belgium 32 0 2 757 00 20 Brazil 55 11 3262 3599 Canada 800 433 3488 China 86 21 6555 7838 Czech Republic 420 224 235 774 Denmark 45 45 76 26 00 Finland 385 0 9 725 725 11 France 33 0 1 48 14 24 24 Germany 49 0 89 741 31 30 India 91 80 41190000 Israel 972 0 3 6393737 Italy 39 02 413091 Japan 81 3 5472 2970 Korea 82 02 3451 3400 Lebanon 961 0 1 33 28 28 Malaysia 1800 887710 Mexico 01 800 010 0793 Netherlands 31 0 348 433 466 New Zealand 0800 553 322 Norway 47 0 66 90 76 60 Poland 48 22 3390150 Portugal 351 210 311 210 Russia 7 095 783 68 51 Singapore 1800 226 5886 Slovenia 386 3 425 4200 South Africa 27 0 11 805 8197 Spain 34 91 640 0085 Sweden 46 0 8 587 895 00 Switzerland 41 56 200 51 51 Taiwan 886 02 2377 2222 Thailand 662 278 6777 United Kingdom 44 0 1635 523545 National Instruments NI ni com and LabVIEW are trademarks of National Instrumants Corporation Refer to the Terms of Use section ni com 1ega1 for more information about National Instruments trademarks Other product and company names mentioned herain are trademarks or trade names of thair respective companies For patents covering National Instruments products refer to the appropriate location Help in your software the patents txt file on your CD or ni com pstents 2005 2006 Natio
58. l known sleep labs to prove the accuracy of this device In addition after patent search only one more device was vaguely related to the purpose of our project It is a Measuring device for quantifying the severity of bruxism US patent 5 911 576 comprising of a thin shell formed to the shape and elastically retained to one or more teeth The shell consists of many layers of different colors The outer layer of the shell when worn out by clenching and grinding reveals an inner layer This way the regions of wear may be analyzed to determine the extent of the bruxing activity However this device does not provide the EMG signals for accurate diagnosis and may not be comfortable to use since it may interfere with normal breathing 1 4 Map for the Rest of the Report The remaining portion of this report will consist of the design constraints safety issues impact of engineering solutions life long learning budget timeline individual team member contributions and additional data to support our final proposal 2 PROJECT DESIGN Originally we had proposed three alternative designs for the realization of the project Alternative Design I had been chosen as the optimal since it is more economic and would require less setup than Alternative Design II which incorporates four BiteStrip like adhesives with Bluetooth wired into each one Alternative Design III would be significantly less costly by incorporating memory into the unique hat
59. l variables for signal multiplexing unsigned char 151 unsigned char sig2 unsigned char sig3 unsigned char sig4 Vini1 0 Vin2 0 Vin3 0 Vin4 0 MuxOut unsigned int unsigned int unsigned int unsigned int unsigned int analog to digital converter ADMUX 0 Select channel ADCSRA 0xC3 Enable ADC amp start 1st dummy conversion Set ADC module prescalar to 8 critical for accurate ADC results while ADCSRA amp 10 Check if conversation is ready ADCSRA 0x10 Clear conv rdy flag set the bit unsigned int ReadADC unsigned char channel unsigned int binary_weighted_voltage binary_weighted_voltage_low unsigned int binary weighted voltage high weighted binary ADMUX channel Select channel ADCSRA 0x43 Start conversion Set ADC module prescalar to 8 critical for accurate ADC results while ADCSRA amp 0x10 Check if conversion is ready ADCSRA 0x10 Clear Conv rdy flag set the bit binary weighted voltage low ADCL Read 8 low bits first Read 2 high bits multiply by 256 binary weighted voltage high unsigned int ADCH 8 binary weighted voltage binary weighted voltage low binary weighted voltage high return binary weighted voltage ADCH ADCL void PWM B_init void DDRB 1 lt lt PORTB4 set output channel PWMOB COMOB1 no inverting mode lt lt WGMO1 1 lt lt wGMOO fast mode 7 Initial
60. layed under the Raw signals tab the rectified and rms EMG signals can be viewed under the Signal Analysis tab and the tabulated results are shown under the Tabulated results tab All of these features make this application significantly helpful for the clinician to diagnose TMJD View EMG Final 2 gt Left Masseter 0 5 4 0 25 2 pj Fas 2 5 1 1 1 1 1 1 1 1 1 1 6 24 00 309 6 24 01 000PM 6 24 01 500 6 24 02 000PM 6 24 02 500 PM 6 24 03 000 6 24 03 500 6 24 04 000 6 24 04 500 PM 6 24 05 309 PM 4 28 2011 4 28 2011 4 28 2011 4 28 2011 4 28 2011 4 28 2011 4 28 2011 4 28 2011 4 28 2011 4 28 2011 Time Right Masseter ai lt t d 0 54 0 25 a Ma 0 25 3 57 1 1 1 6 24 27 509PM 6 24 28 000PM 6 24 28 500PM 6 2429 000 6 24 29 500 6 24 30 000PM 6 24 30 500PM 6 24 31 000PM 6 24 31 500PM 6 24 32 000 6 24 32 509 PM 4 28 2011 4 28 2011 4 28 2011 4 28 2011 4 28 2011 4 28 2011 4 28 2011 4 28 2011 4 28 2011 4 28 2011 4 28 2011 Time Left Temporalis zil E 0 5 0 E 5 0 5 di D D 1 6 23 58 311PM 6 23 59 000PM 6 23 59 500 6 24 00 000PM 6 24 00 500 6 24 01 000 6 24 01 500 6 24 02 000 6 24 02 500 PM 6 24 03 311PM 4 28 2011 4 28 2011 4 28 2011 4 28 2011 4 28 2011 4 28 2011 4 28 2011 4 28 2011 4 28 2011 4 28 2011 Time Right Temporalis J 0 5 a
61. mum period an error will occur Moreover this device does not save the EMG signals which may be useful for the clinician in order to assess an accurate diagnosis Bitestrip only provides the number of bruxing events This information will not allow the clinician to distinguish between teeth grinding and clenching nor record the intensity of the clenching or grinding the time when these events occur Sakagami Horii Ino Matoba Kato and Kawanami developed a portable nocturnal bruxism monitoring and analysis device in 2002 and verified its accuracy and easiness of use Their bruxism diagnostic system consisted of two parts the portable bruxism monitoring and analysis device and the software that was installed to a computer The monitoring and analysis device Morita MFG was equipped with a microcomputer to auto analyze the data Due to the small size of this device and its light weight it could be either placed on the forehead or inserted in a pocket of a jacket The device had two sets of data import connectors for pick up cables which were hooked to the disposable electrodes Duotrode Myotronics Inc USA attached either to both sides of the cheek over the masseter muscles or to both sides of the temple over the temporalis muscles In order to launch the device the user would push the start button on the side of the device After amplification and processing of the EMG signals these were compared to a manually set threshold level
62. n the voltage exceeds 700 mV forward biased The diode protection circuitry is shown in Fig 11 Electrode Amplifier lt gt 01 FDH333 FDH333 Figure 11 Patient protection circuitry FDH333 high conductance low leakage diodes were utilized due to their low reverse current when they are forward biased This ensures that maximum current is shorted to ground when a large voltage potential exists across the diodes The FDH333 diodes were tested and successfully shorted the current to ground when the voltage exceeded 600 mV Thus this configuration provides good electrical protection for the patient s safety Another method for electrical shock protection is the use of the AC DC wall transformer providing isolation from the patient and the AC wall voltage Since there is no galvanic connection between the patient and the wall current cannot flow directly from the wall to the patient The cautious user should however always plug the TMD Diagnostics System into a surge protector to ensure that no electrical surge damages the components and cause potentially harmful current to pass to the patient The reader should note that EMG signals typically do not exceed 90 mV however it is important to protect the patient regardless The diode circuit and wall transformer design is inexpensive and easy to implement into the circuit and therefore should always be included in future applications The patient should be rest assured that th
63. nal Instrumants Corporation All rights reserved 371728B 01 Apr06 TMJD Diagnostics System Senior Design Spring 2011 71
64. nd counting each bruxing episode a permanent chemical display for presenting the study outcome in the morning and lithium battery All the elements are integrated onto a small lightweight plastic film that is attached to the patient s cheek The BiteStrip device is shown in Fig 1 Electrochemical display Indicator light 2 pre gelled CPU and electronics EMG electrodes on back Figure 1 Components of the BiteStrip Its indications correlate well with comparable indications from formal sleep lab studies It is available through health providers worldwide at a very low price to the public as a self administered or prescription test Relevant patents were applied for and clinical studies are in process in well known sleep labs to prove its accuracy In using Bitestrip the patient is required to perform at least two maximal voluntary clenches during the first 30 minutes by biting on a wooden spatula provided in order to establish the threshold which is set at 30 of the average EMG amplitude The BiteStrip counts each EMG peak stronger than the threshold for a TMJD Diagnostics System Senior Design Spring 2011 3 period of up to six hours The patient then returns the Bitestrip to the clinician for interpretation of the results Despite the advantages offered by Bitestrip the device presents some limitations In the first place the study requires a minimum of 5 hours If the Bitestrip is removed earlier than this mini
65. nd it proved to sufficiently attenuate frequencies above 500 Hz The highpass filter is shown in Fig 16 TMJD Diagnostics System Senior Design Spring 2011 18 5 24 3 vcc 10 5 9v 01 9v 1N4001GP D2 1N4001GP C5 C6 UB 0 1uF 0 1uF x C1 HIGHPASS EE 120 Vrms L074ACD 0 022uF 60 Hz 14 0 VDD 9V Figure 16 Fourth order highpass filter with cutoff frequency 25 Hz The cutoff frequency of this filter is 25 Hz to ensure that frequencies below the 3 dB passband are attenuated Once again the TL074 quad op amps were utilized in the design An simulation was performed using Multisim 11 0 as shown in Fig 17 AC Analysis 10 1 400m 100m 40m 10m 4m Magnitude 1 400p 100 40 10 1 4 7 10 40 70 100 400 700 1k 4k 7k 10k 40k 100k Frequency Hz Figure 17 AC simulation for the highpass filter It is evident from Fig 17 that the filter sufficiently attenuated frequencies below 25 Hz Protoboard testing of the lowpass filter was conducted and it proved to sufficiently attenuate frequencies below 25 Hz The lowpass and highpass filters were connected in the physical circuit for protoboard testing using the TL074 JFET quad operational amplifier The results are shown in FIGS 18 19 20 and 21 TMJD Diagnostics System Senior Design Spring 2011 19 Tek Trig d Pos 0 0005 SAVE REC
66. ng rectified signals of the four muscles 3 REALISTIC CONSTRAINTS There are a number of constraints related to our design of the device that are worth mentioning Many studies have found that bruxism is highly associated with Obstructive Sleep Apnea Patients who are under treatment of this sleep disorder wear a Continuous Positive Air Pressure CPAP device which is a mask like machine that provides a constant stream of air which keeps the patient breathing passages open while they sleep An illustration of a standard CPAP device is shown in Fig 50 TMJD Diagnostics System Senior Design Spring 2011 43 Figure 50 Standard device Due to the fact that patients who suffer from Obstructive Sleep Apnea are likely to brux when constructing the design of our wearable hat we took into consideration that it could not interfere with the CPAP device Ideally the patient suffering from Obstructive Sleep Apnea should be able to wear both the CPAP device and the bruxism diagnostics device as comfortably as possible Another observation is that most of the temporalis muscle is covered by hair If the electrode were to be placed on hair the signal may be significantly distorted due to the high input impedance from the electrode skin interface Therefore it is important to correctly place the electrode to ensure optimal acquisition of the signal Another constraint has to do with the size of the hat Because patient
67. odes were utilized in the final design however any electrode with a snap connection may be substituted The disposable electrodes are shown in FIG 9 Figure 9 Kendall Tyco ARBO surface EMG electrodes These electrodes have a unique patented pre gelled adhesive side with non irritating gel especially developed to prevent allergic reactions They are latex free and therefore suitable for every skin type The snap on connector can easily be pushed on or removed from the electrode lead resulting in optimal user friendliness The gel adhesive is not greasy compared to other electrode gels and maintains incredible adhesion despite rigorous stress and strain tests The electrode circuitry is shown in Fig 10 Electrode V R1 PatientProtection 100kQ Figure 10 Electrode input circuitry The 100 resistor increases the input resistance which is desirable for biopotential amplifiers Patient protection circuitry follows the 100 resistor to ensure that both the patient and the circuit components are protected 2 1 2 4 Patient Protection TMJD Diagnostics System Senior Design Spring 2011 14 A major safety concern is that of electrical shock to the patient Since the patient will have electrodes attached to them with potentially harmful voltages during long periods of unconsciousness protection from electrical shock is of vital importance Silicon diodes offer excellent protection to patients by conducting current whe
68. oid 50 1 Use channel 1 ADON 1 Turn A D on __ 1 30 delay 30 usec to settle A D acquisition ADGO 1 Start conversion while ADGO wait for ADGO to go off signalling end of conversion Speed ADRESH int main void int 1 0 Initial DisplayC 0x80 Lab 10 SerialString UCONN Huskies for t c SerialReception if i 16 0 clear_display TMJD Diagnostics System Senior Design Spring 2011 59 DisplayC 0x80 Lab 10 DisplayCharacter xC0 i c i 12 4 Bluetooth Serial Connection Code in Embedded C include lt htc h gt void InitSerial void 5 0600100100 Enable TXEN and BRGH RCSTA 0610011000 Enable SPEN and CREN SPBRG 47 9600 Baud for 7 37MHz TRISC7 1 Set C7 RX as input TRISC6 0 Set C6 TX as output RPO 0 Force bank 0 void SerialString const char str for str str while TXIF set when register is empty continue TXREG str void SerialCharacter unsigned char c while TXIF set when register is empty continue TXREG c char SerialReception void while RCIF set when register is not empty continue return RCREG 12 5 Data Sheets Due to the size of the datasheets for the AD620 and 074 they have been shortened to show critical information including important parameters and applications information
69. ok Signal Multiplexing time division MUX of four inputs into output SN EE AE AE ok oe doles a A a aE EE void SignalMultiplexer void PORT directions DDRD xFE DDRA exE6 Read in signals 181 ReadADC 1 sig2 ReadADC 2 TMJD Diagnostics System Senior Design Spring 2011 57 77 153 154 ReadADC 3 ReadADC 4 Convert to voltage I Vin1 100 sig1 5 001 1023 27 Vin2 100 sig2 5 001 1023 Vin3 100 sig3 5 001 1023 Vin4 100 sig4 5 001 1023 Time Division MUX 77 1 MuxOut _delay_ms 1 MuxOut Vin2 77 _delay_ms 0 1 77 MuxOut Vin3 _delay_ms 0 1 y MuxOut Vin4 delay ms 0 1 Vin1 OC2A pt picop k kk ik 2K K 2K K K x K X X K X XK X X X X XK X K XK X X K K X K K X K K K X XX oe X K K X K K CE CE CE K CE CE K K X K CE K K CE CE K K CE CE K OK K X K K K K K K MAIN PROGRAM KK K K K K K K K K K K K K K K K K K K K K K K K K K K K K K K K K K K K K K K K K K K K K K K K K K K K K K K K K K K K K K K K K K K K K K K K K K K deo ELE ELE ESS PELE EEL PEER qot doe dee y int main void Initialize ADC InitADC Initialize PWM PWM B_init whil
70. onsult your user ERU Program Running I n em 2IntermetE Bi TMDDiagnostic Search Desktop 5 Figure 41 TMJD Diagnostics showing instructions and light indicating the program is running The patient will click on the Thresholds tab in order to enter the values of thresholds indicated previously by the clinician as shown in Figure 42 TMJD Diagnostics System Senior Design Spring 2011 36 E TMJDiagnosticsTest_Final 1 1 vi Patient View Thresholds Clinician View W University of Connecticut Right Masseter Threshold 9 02 Left Masseter Threshold g o Right Temporalis Threshold B o Left Temporalis Threshold D 0 2 2 Internet E gt 2 Windows TMIDiagnostic Figure 42 Threshold tab of TMJD Diagnostics Application program for data acquisition At this point data acquisition will begin and the patient should verify that signals are displayed on the Clinician View tab when clenching and grinding as shown in Figure 43 After this verification the patient can proceed to sleep Data will be displayed in real time and acquired over the period of time until the patient awakens TMJD Diagnostics System Senior Design Spring 2011 37 View Final 2 vi Left 0 5 E 0 25 8
71. ortable and expensive In addition the design of the Neuroband is unique in that it secures the electrodes in place efficiently and allows for repeated usage since it can be washed The TMJD Diagnostics device also provides the clinician with valuable diagnostic information Not only the raw EMG signals are displayed but also the rectified and rms EMG signals Moreover data is processed to provide tabulated results showing total number of bruxing events per muscle the total duration of the events and the exact times of occurrence of these events Current devices do not offer these features which are helpful for an accurate diagnosis of TMJD Finally the light weight and portability of the system make it optimal for home use All of these features are vast improvements on the current techniques for temporomandibular joint disorder diagnosis 10 REFERENCES Cram Jeffrey Introduction to Surface Electromyography 1st Jones amp Bartlett Publishers 1998 Print Crider Andrew Alan G Glaros and Richard N Gevirtz Efficacy of Biofeedback Based Treatments for Temporomandibular Disorders Applied Psychophysiology and Biofeedback 30 4 2005 333 45 Print Doering S J Boeckmann S Hugger and P Young Ambulatory Polysymnography for the Assessment of Sleep Bruxism Journal of Oral Rehabilitation 35 2008 572 76 Print Galaros A G Z Owais and L Lausten Reduction in Parafunctional Activity a Potential Me
72. quires patients to wear adhesive electrodes with wire attachments limiting the patient s mobility and comfort during sleep Studies utilizing these methods can produce inconsistent results due to the patient s discomfort in a different environment and the complexity of the equipment attached to their body This design project seeks to eliminate the necessity for sleep labs and allow patients to be screened comfortably in their homes while maintaining the accuracy and efficacy of standard sleep labs Our design has unique features such as the hat like data acquisition unit that the patients will be able to wear comfortably in their home environment and a laptop to acquire store and display data to the user As a result the end product will be comfortable and user friendly for both the patient and the clinician The data acquisition in the patient s home will ensure that it is consistent with their natural sleeping habits All in all our design will greatly improve the screening and diagnosis of TMJD 1 INTRODUCTION 1 1 Background Temporomandibular Joint Disorder TMJD affects approximately 35 million people in the United States It can cause problems with eating drinking swallowing talking making facial expressions and even breathing in people who suffer from it Bruxism can wear down the fibrocartilage discs in the jaw which makes it difficult to open and close the mouth Bruxism the act of grinding or clenching of the teeth is
73. r Joint Disorder thus they were tested against the team member that did not have the disorder as a control Tests were done over periods of 4 6 hours to ensure that data could be TMJD Diagnostics System Senior Design Spring 2011 34 collected over this extended period of time The tests were successful as accurate EMG signals were obtained as well as accurate tabulated results The Neuroband Data Acquisition unit is made up of nine snap electrode leads and Diane s Neuroband FIG 39 The nine snap leads are organized over the four muscles associated with bruxism as well as over the forehead for ground Figure 39 Neuroband unit with snap electrode leads built in The leads of the Neuroband are organized by color for the muscle and plug into the DIN ports to connect to the circuitry enclosure These ports are labeled with a Y for yellow B for blue G for green for red and a black dot for black LABVIEW PROTOTYPE DESCRIPTION Two LabVIEW executable files were developed for data acquisition storage analysis and display The TMJD Diagnostics Application will be run by the patient before sleeping The interface is user friendly and instructions are provided at the start of the program as shown in Figure 40 Additional help is also provided by clicking on the Help button located in the upper middle of the screen as shown in Figure 41 green light indicates that the program is running TMJ
74. r data acquisition Display HIE View EMG TRUE Select muscle Select file Read from file Rectify EMG Rms EMG Fig 34 LabVIEW program flowchart for data display 2 2 Prototype The Temporomandibular Joint Disorder Diagnostics System employs electromyography on the facial muscles to detect bruxism events for the diagnosis of TMJD The EMG signals are amplified and filtered by the circuit The USB 6008 DAQ acquires the data from the circuit converts it to a digital signal and passes the data to the laptop equipped with LabVIEW software The LabVIEW software then further processes the data and allows the user to see raw rectified and RMS voltage electromyographic data The program also tabulates the raw data so that the clinician can view the amount of bruxing events per muscle how long each muscle spent bruxing and the exact times each muscle bruxed TMJD Diagnostics System Senior Design Spring 2011 31 The circuit consists of protection circuitry to protect the patient from electric shock an instrumentation amplifier to amplify the EMG signals from the uV range to usable potentials a bandpass filter to remove undesired frequencies and a data acquisition board to acquire and convert to digital signals The circuit is discussed in detail in the Subunits section of this report The results of the electromyographic data tests are shown in FIG 35 Patient Vi
75. raphs EEG The disposable electrodes are secured in the Neuroband using snap electrode leads placed inside the device over the muscles of mastication The snap electrode leads are removable so that the device can be washed between uses The electrode leads are connected to a DIN connector cable which is attached using a D sub connector to the circuitry The circuit is enclosed and is connected via USB to the laptop computer Velcro is utilized to allow for minor adjustments and achieve an optimal fit The EMG signals are sent serially to a laptop computer An executable LabVIEW program automatically loads each time the computer is powered on The interface is easy to use and provides sufficient help information in addition to a detailed user manual The user will simply run the program and initiate the data acquisition process The program will have the capability to analyze send store and display data The raw data will be processed into useful diagnostic information that may be presented to the clinician In order to test the device subjects with TMD and control subjects will be employed in clinical trials Therefore an institutional review board IRB must be TMJD Diagnostics System Senior Design Spring 2011 10 applied for in consideration of clinical trials This will be possible with the help of the UConn Health Center and School of Dentistry 2 1 2 Subunits 2 1 2 1 EMG Circuit Analog circuitry must be utilized in order to amplify
76. rough the DAQ Assistant and splits the signals into the four different muscles for analysis Before handing the device to the patient the clinician selects the thresholds above which he desires EMG data to be saved The patient will be in charge of clicking a Start button located under the EMG Acquisition tab in order to begin data acquisition A green light will indicate that data acquisition has begun When the signal of a muscle exceeds a threshold preselected by the clinician indicating relevant muscle activity a portion of the signal is written to the file corresponding to that specific muscle This way we save memory by not storing data when bruxism events are not present The Stop button will end the data acquisition When the patient returns the device to the clinician he is able to view the EMG data saved The clinician can select a muscle through the different tabs Using a path control the clinician selects which muscle s activity he wants to view and of what date There is also the option to adjust the speed at which the data is displayed Moreover a scrollbar allows the clinician to scroll over the data Fig 33 displays the flow charts that describe the functionality of the LabVIEW code TMJD Diagnostics System Senior Design Spring 2011 30 Data Acquisition Data gt Threshold Start DAQ TRUE Split signal Extract Portion of Signal Write to file Fig 33 LabVIEW program flowchart fo
77. rovide a better solution for the diagnosis of this sleep disorder For example we proposed non adhesive electrodes that will improve the comfort of the individuals when placing them in the different locations on the face and the use of wireless technology to allow more freedom of movement for the patient during sleep We also gained experience working as a team having to exchange opinions and debating different ideas as well as having to meet strict deadlines Moreover we experienced the relationship with a client and the fact of dealing with a limited budget to carry out the project This implies that every specification of our design should meet the needs of our client in order to ensure the satisfaction of the final product at the same time that we carefully select our design in order to stay within our budget In our design we included the EMG circuit and a LabVIEW program to process the data Although we were familiar with both tools throughout academic courses this time we are applying them to solve a real need By collecting EMG signals from individuals who suffer from bruxism we learned the patterns that characterize clenching and grinding of the teeth that allow for the diagnosis of the disorder 7 BUDGET 7 1 Budget The total prototyping costs came to a total of 2 451 07 The total cost device would 1836 02 The cost of each device 15 outlined in Table 53 We were allotted a total budget of 6 000 were under budget
78. s head shapes and sizes vary we designed a device that is fully adjustable for all head sizes This is accomplished using a Velcro hook and loop fastener system Finally the use of the device requires handling a large amount of data throughout a long period of time without technical supervision Hard disk memory is also limited Therefore the LabVIEW program that will continuously receive the EMG data analyze it and store it might experience unexpected errors while operating during the night This would imply that the whole set of data would be lost In order to avoid this we maximized the efficiency of data transfer and storage by writing to a LabVIEW measurement file 4 SAFETY ISSUES This project is relatively safe and does not pose significant harm to any of the users However great care must go into considering all aspects of safety so that nothing is overlooked TMJD Diagnostics System Senior Design Spring 2011 44 The patient using the device will be in unconscious period of sleep when in use Thus they will not have the cognitive capacity to react quickly to a safety hazard One safety concern is that of electrical shock The patient will have numerous electrodes attached to their skin that may exhibit hazardous voltage potentials Fig 51 depicts the levels of electrical current corresponding to physiological response Millamperes Irregular Heart Rhythm Muscular Control Let go Threshold Perception Figur
79. staff required to observe the patient and assure that the test is going well This would also make the device less expensive for the patient Secondly since sleep labs would no longer be needed for the diagnosis of TMJD some may close due to a decreased demand and some technicians may be out of work There is no similar device to this one on the market so if successful this product may be the only one like it and would initially have a monopoly on the market share This would not last very long as it would create competition within the industry TMJD Diagnostics System Senior Design Spring 2011 46 Figure 52 Patient wired sleep lab The proposed device is desirable for patients as well as clinicians TMJD goes undiagnosed in many sufferers due to the inconvenience of going through testing in a sleep lab The TMJD diagnostic device will take less time out of the patient s day than trip to the sleep lab would This could ultimately result in more activity for specialists in the sleep disorders field and comfort from treatment for those who suffer from TMJD 6 LIFE LONG LEARNING In order to carry out the project new knowledge was acquired through intensive research of material To begin with we learned about the bruxism sleep disorder characteristics and symptoms Moreover we explored the current diagnosis methods for bruxism and their drawbacks Based on these we searched for new materials and methods with the aim to p
80. t was modified in order to adapt to our application However due to a change in our project design this code was not used I also did research regarding Bluetooth interfacing but due to a time constraint this design was not used I have also contributed to the selection of the disposable electrodes that have integrated gel and features a snap on connector that can easily be pushed on or removed from the electrode lead I created a front panel design that is very user friendly and includes different tabs for the specific functions of the program There is one tab per muscle one tab that allows the clinician to set the thresholds and another tab for the patient s view The muscles tabs include the views of the EMG of the rectified EMG and the RMS EMG There is also a path control for selecting the file to view A push button initiates and stops the display of signals The tab for threshold selection allows the clinician to select a threshold for each muscle for signal recording A Save button saves the value into a file The tab for the patient s view includes a Start Stop button and a green LED that indicates that data acquisition has begun On the left side of the front panel there is a slider control to adjust the velocity at which signals are displayed I also carried out research on existing products and concluded that our design would offer advantageous features compared to them Our design features a unique Neuroband Data Acquisi
81. team website throughout both semesters by uploading all recent documents and ensuring that all information was current I contacted multiple companies for the electrode leads and had difficulty in finding male 1 5 mm touch proof connectors to interface with the snap electrode leads Ultimately I discovered Bioconnect who provided us with some free samples as well as the cables that are utilized in the final product A Bluetooth wireless interface was attempted but was eliminated from the final product strictly for time constraint reasons For future applications adding Bluetooth capability will be a major improvement over a wired connection The circuit was designed to operate from 9 V so portability is possible and the PCB would not have to be significantly altered I designed ordered populated and tested the PCB The design stage took about a week because I checked connections multiple times to ensure that another PCB would not have to be order Fortunately the PCB worked right from the power up and never presented any problems I can confidently say that the design is solid and all future improvements should keep a relatively similar design TMJD Diagnostics System Senior Design Spring 2011 50 I designed ordered and assembled the enclosure In terms of durability the enclosure should provide a good level of protection to the circuit and internal components It is advisable that the user should not drop the device or expose the
82. the receiving laptop may TMJD Diagnostics System Senior Design Spring 2011 27 be across the user s room A Bluetooth interface was attempted early in the semester but was substituted with a wired connection later in the semester due to time constraints Future applications should consider employing Bluetooth due to its improvements over a wired connection The BlueSMiRF Gold Bluetooth module by SparkFun Electronics was selected due to its low cost 64 95 and RX TX capabilities It consumed a low amount of current 25 mA featured an encrypted connection had a range of 350 feet and could be operated by a single power supply of 3 3 6 V The BlueSMiRF module is shown in FIG 29 Figure 29 BlueSMiRF Bluetooth module from SparkFun Electronics A Bluetooth USB dongle AZiO BTD V201 USB 2 0 Micro Bluetooth Adapter was ordered to interface with any laptop By using this device any computer equipped with the TMD Diagnostics System Application could be used to acquire data provided that the computer met the specifications The USB dongle is shown in FIG 30 Figure 30 USB Bluetooth dongle for adaptation to nearly any personal computer Some code Embedded C was attempted to establish a Bluetooth connection This code was designed for use on a Microchip microcontroller but can be modified to operate with any library file such as AVR This code is included in the Appendix of this report and may be used by anyone without the consent of the
83. tion Unit and provides the clinician with useful information for TMJD diagnosis Not only it provides the raw EMG data but also the rectified and RMS signals Finally in order to make our design safer for the patient I proposed the use of a coiled cable to connect the laptop to the circuit enclosure This way the movement of the patient will not pull the laptop away so easily 9 CONCLUSION TMJD Diagnostics System Senior Design Spring 2011 52 TMJD Diagnostics device improves the screening and diagnosis of TMJD by providing benefits to both the clinician and the patient The device proved to acquire accurate data while allowing the patient to be screened comfortably at home It also presents advantageous features such as user friendliness portability and the possibility of repeated usage since it is washable The fact that this device maintains the accuracy and efficacy of sleep studies while providing the patient with the comfort to be screened in their home environment make it extremely beneficial for the patient and the patient The clinician does not need to instruct the patient in the usage of the device since simple instructions are provided to the patient at the beginning of the TMJD Diagnostics application The interface is very user friendly and additional help is provided if needed The patient will be screened in the natural sleeping habits since he will not be required to stay overnight in a sleep lab which is often uncomf
84. tric s reusable Ag AgCl electrodes These particular electrodes are designed for applications requiring lightweight and smaller electrodes They may be applied to the skin with or without electrode gel but for our purposes they were applied without gel The lead wires are strong flexible and fatigue resistant providing for long life and sustainability The results of reusable electrodes are shown in FIG 8 Signal Power Spectrum RMS Rectified Integral Compilation Unfiltered 2 Amplitude V 3041 3 49 08 647 3 2 2011 Time Rectified 2 D 3 49 13 647 PM 3 2 2011 E aie E 34908545 3 2 2011 3 2 2011 wwmna H RMS 2 TE Amplitude V Ir cg e 3 49 08 646 PM 34913546 PM 3 2 2011 3 2 2011 uu 3l Filter Selection DC Offset STOP 25 500Hz 10 1582 Volts Figure 8 Reusable electrode test It can be seen from FIG 9 that the signal quality of the reusable electrodes is excellent and reproducible However they were difficult to maintain adhesion to the skin for extensive periods of time and for this reason they were removed from the final product design Alternatively disposable surface electrodes were implemented in the final product due to their superior adhesion and improved signal quality Kendall Tyco TMJD Diagnostics System Senior Design Spring 2011 13 ARBO 24 mm surface EMG electr
85. ts of patents or other rights of third parties which may result from its use No license is granted by implication or otherwise under any patent or patent rights of Analog Devices TMJD Diagnostics System CONNECTION DIAGRAM 8 Lead Plastic Mini DIP Cerdip Q and SOIC R Packages TOP VIEW 1000 Furthermore the AD620 features 8 lead SOIC and DIP packaging that is smaller than discrete designs and offers lower power only 1 3 mA max supply current making it a good fit for battery powered portable or remote applications The AD620 with its high accuracy of 40 ppm maximum nonlinearity low offset voltage of 50 uV max and offset drift of 0 6 uV C max is ideal for use in precision data acquisition systems such as weigh scales and transducer interfaces Fur thermore the low noise low input bias current and low power of the AD620 make it well suited for medical applications such as ECG and noninvasive blood pressure monitors The low input bias current of 1 0 nA max is made possible with the use of Superfieta processing in the input stage The AD620 works well as a preamplifier due to its low input voltage noise of 9 nV VHz at 1 kHz 0 28 uV in the 0 1 Hz to 10 Hz band 0 1 2 input current noise Also the AD620 is well suited for multiplexed applications with its settling time of 15 ts to 0 0196 and its cost is low enough to enable designs with one in amp per channel RTI VOLTAGE NOISE 40 1 1092

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