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

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Block Diagram

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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

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Mounting Wireless Sensor

• 2 XBee Transmitters

• 2 Accelerometers - ADXL335

• Power Source – Coin Battery Rechargeable• Lithium Coin Cell

• 3.7V @ 200mAh

• Inexpensive

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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

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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:

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Accelerometer Model

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Outline

I. Background

II. Key Design Components

III. Demonstration

IV. Complete Design Overview

V. Future + Timeline

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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

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Timeline

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Questions?