SMART BRACETaylor Ellsworth

Advisor: Professor Buma

Motivation and Goal• Knee injuries are prevalent in today’s society• Rehab programs are not geared towards the specific

individual• Is there a way to track an individual’s rehab progress?

User Requirements• What will the Smart Brace record?

• Range of Motion • Velocity

• When to use?• Rehab Exercises

• How long to record?• 1 Hour Total• 2 Minute Exercises

• User Interface?• Max values of Range of Motion and Velocity• Plot showing Angle and Velocity vs Time

System Block Diagram

Outside of Knee Inside of Knee

PotentiometerGyrometer

Arduino Uno

Sensor• Potentiometer

• 5K Ohms• Linearity = +/- 0.25%• Tolerance = 5%

• Gyrometer• Measurement Scale = +/- 500 degrees/sec

Microcontroller

• Arduino Uno• 14 Digital I/O Pins• 2KB SRAM• Bluetooth Communication

Data Transmission via Bluetooth• Length of Exercise

• 2 minutes

• Sampling Rate• 100 samples/sec

• Memory Used Up• 0.047KB of SRAM

• Transmitting Data• Package and send 5B of data at a time to Smartphone using

Bluetooth

Smartphone App• User Display

• Samsung Galaxy S4• Start/Stop button to begin and end capturing data• Max value of knee angle and angular velocity• Plot showing Angle and Velocity vs Time

Testing and Schedule • Potentiometer/Gyro

• Using basic circuit and lab equipment• Attached to knee brace

• Obtaining data with microcontroller• Send data to laptop• Smartphone Application

• Fall Term:• Week 7-10: Test potentiometer/gyro

• Winter Term:• Week 1-5: Transfer of Data to Computer• Week 6-8: Transfer of Data to Smartphone App• Week 9-10: Final Project Report

BudgetItem Price

Breg Fusion Knee Brace --

Arduino Uno $24.95

SparkFun Bluetooth Modem for Arduino Uno

$24.95

Potentiometer $17.35

Gyrometer $49.95

9V Battery Snap Connector with Power Plug

$1.50

Energizer LA522 Batter – 9V

$6.95

Samsung Galaxy S4 --

Total Cost $125.65

Questions?

Microcontroller• Arduino Uno

Digital I/O Pins 14

Analog Input Pins 6

Flash Memory 32 KB

SRAM 2 KB

Weight 25 g

Size 58.6 mm x 53.4 mm

Potentiometer• ETI Systems 882-MW22B-3-5K

Resistance 5K Ohms

Linearity +/- 0.25%

Tolerance 5%

Number of Turns 3

Weight 0.8 oz

Size 1.57” x 0.88”

Gyrometer• SparkFun Tri-Axis Breakout L3G4200D

Measurement Scales +/- 250, +/- 500, +/- 2000

Sensitivity 17.50 mdps/digit

Supply Voltage 2.4V-3.6V

Size 2.3cm x 1.75cm

Calculations