Electrical and Computer Engineering
Motion Analyzer for Physical Therapy
(MAPT)
SDP10 - Comprehensive Design Review
Arjuna Baratham (CSE) - Sean Klaiber (EE) - James Rutter (EE) - Constantina Tyes (EE)
Professor Soules
Advisor, Senior Lecturer, ECE
February 12th, 2010
2Electrical and Computer Engineering
Outline
I. Design Review
II. Key Design Components
III. Demonstration
IV. Complete Design Overview
V. Future + Timeline
3Electrical and Computer Engineering
Problem and Solution
Reliable Quantitative Data in Physical Therapy (PT) can only be Collected with a One-on-One Patient/Therapist Interaction
Create a simple, inexpensive, and portable device that can accurately measure physical therapy related motion
4Electrical and Computer Engineering
Block Diagram
5Electrical and Computer Engineering
Progress Since MDR
• Beagleboard platform:
• Wireless USB interface
• Processing sensor data in Python
• Audio feedback
• Shell scripts for files and memory
6Electrical and Computer Engineering
Outline
I. Background
II. Key Design Components
III. Demonstration
IV. Complete Design Overview
V. Future + Timeline
7Electrical and Computer Engineering
Wearable Sensor
• Zigbee Transmitter
• 45mA @ 3.3V
• ADXL335 Accelerometer
• 4mm x 4mm x 1.45mm, 350uA @ 3.3V
• 9V Battery-Power Supply
• Voltage Regulator 3.3V
8Electrical and Computer Engineering
Mounting Wireless Sensor
• 2 XBee Transmitters
• 2 Accelerometers - ADXL335
• Power Source – Coin Battery Rechargeable• Lithium Coin Cell
• 3.7V @ 200mAh
• Inexpensive
9Electrical and Computer Engineering
Processing and Display
• Counterpart XBee wireless receiver plugged into USB on BeagleBoard
• All pitch values plus timestamp logged into .txt file
• Gobetwino software listens to serial port for specific commands• Logs all pitch values with timestamp in .txt file
• GNU Octave processes info in .txt file• Plots Pitch vs. Time
10Electrical and Computer Engineering
Demonstration
11Electrical and Computer Engineering
Outline
I. Background
II. Key Design Components
III. Demonstration
IV. Complete Design Overview
V. Timeline
12Electrical and Computer Engineering
Wireless Transceivers
• XBee Series 1 radios• 1 mW transmit power
• 250 Kbps data rate
• Flexible pin arrangement
• Configuration• 3 analog sample every 3ms (100 Hz)
• 57600 bps baud
• 30 byte packets
Start Byte Data ChecksumLength
MSB LSB0x7E Up to 105 bytes 1 Byte• XBee packet format:
13Electrical and Computer Engineering
Accelerometer Model
14Electrical and Computer Engineering
Outline
I. Background
II. Key Design Components
III. Demonstration
IV. Complete Design Overview
V. Future + Timeline
15Electrical and Computer Engineering
Team Roles
Sean
GNU Octave, Gobetwino script, power research
User/PT Interface
James
Accelerometer code, BeagleBoard research
Accelerometer development, BeagleBoard processing
Arjuna
Wireless links, accelerometer research
Both wireless sensors and integration with PSFD
Constantina
Mounting WS, power and accelerometer research
SD card storage, Wireless sensor mounting and power
16Electrical and Computer Engineering
Finances
Already purchased:
Anticipated costs:
Part # Description Quantity Unit Price Total PriceWRL-08664 Xbee Radio 2 22.95 $45.90
v1.1 Xbee Adapter Kit 2 10.00 $20.00900.002 Xbee USB Board 1 29.95 $29.95
SEN-09269 3D Accelerometer 1 24.95 $24.95EPS050100-P6P 5V Power Supply 1 7.16 $7.16
Total $127.96
Part # Description Quantity Unit Price Total PriceWRL-08664 Xbee Radio 1 22.95 $22.95
v1.1 Xbee Adapter Kit 1 10.00 $10.00SEN-09269 3D Accelerometer 1 24.95 $24.95
Wireless Sensor PCB 3 33.00 $99.00
Total $156.90
17Electrical and Computer Engineering
Timeline
18Electrical and Computer Engineering
Questions?