Biofeedback System for Propulsion Training February 22, 2007 Group Members: Noah Reding Nick Chadwick Tom Soike Project Sponsor: Dr. Mark Richter, MAX Mobility Faculty Advisor: Dr. Paul King, Vanderbilt University

MAX Mobility Lab Operating Treadmill with possible incline Multiple PCs for data collection Radio transmitters for communication

Lab Safety Precautions Rising elevator for patients’ use Safety harness attached to chair on treadmill Discomfort scale for patients Emergency stop button for treadmill

Problem of Interest Currently, there are over 2.5 million 1 Americans who are confined to wheelchairs. Some users propel themselves improperly, leading to damage of their upper extremities later in life.

Project Goal Develop software that works with an established propulsiometer to effectively “teach” new and existing wheelchair users proper propulsion methods, in hopes of reducing their chances of developing injuries of the upper extremities later on.

People Affected Approx. 65% wheelchair users experience upper extremity pain or injury 2 Research has linked a relationship between impact stresses placed upon the wrist, elbow, and shoulder during propulsion to upper extremity injury 2

Market Analysis Currently, the personal mobility device industry is a $2-3 Billion operation 3 Constructive surgeries for extremities start at $10,000 and can greatly increase US demand for mobility devices and wheelchairs is projected to increase 6.9% annually and is expected to reach $7.4 Billion by Our primary targets are physical therapist treating handicapped individuals, In the US alone there are more than 77,000 practicing physical therapists 5

Population Change

Performance Criteria To improve a pre-existing device for the capturing of real-time propulsion data Relay this data to a user-friendly interface, allowing for instantaneous alterations of one’s push tendencies. Data to be collected and analyzed: –Push frequency –Push angle –Peak force –Tangential force –Peak loading rate

Existing Solutions Smart Wheel from 3Rivers Measures: 1. Average force of push 2. Length of push 3. Smoothness of push 4. Push frequency Disadvantages: 1.Only fits one size of wheel 2.No real-time data relay 3.Costs $22,500

Our Primary Objective Collect and analyze data in real-time Fits any size wheel Develop a program in LabVIEW that can collect and analyze real-time data from the device. The data will be compared to the proper propulsion technique determined from research companies in the future.

Hardware Work Mini-Dat Computer collects all data with load cells Radio transmitter sends data to PC Frame with hardware fits on all-size wheels Connected new angle sensor to existing hardware for data collection

Solution Description 7 Different Channels of Data Separate Into Each Channel Gather Offset Data for Each Subtract Offset From Each Perform Calculations Obtain 5 Variables of Choice

Further Breakdown of Solution Offset Removal –Apply to each channel –Coincide with each angle Filtering of Data –If needed Calibration Matrix –Comes from manufacturer –Scales data

Factors Involved 1. New angle sensor More sensitive measurements ($40) 2. Simplify software so that only one application is needed Enables faster data collection and calculation Matlab and LabVIEW combined into one ($0) 3. Providing data to the user in an interface Currently in developed stages

Performance Metrics Perform all calculations in < 1 sec. Sampling rate of 200 Hz Relay information through user-friendly interface Improving Cost/Benefit –New device will be cheaper than existing technology ($22,500 vs. $12,000) and provide real time measurement

System and Environment Wheelchair User Propels Data collected Sent to computer Programs analyze and Interpret data LabVIEW program(s) Data read by user; Improves method Data sent to user interface

Project Flow Chart Learn to use Programs Collect Sample Data Interpret Sample Data Assess Problems / Concerns Redesign Programs Interpret Real Time Data Assess Progress / Direction For Interface Meet with Advisor / Discuss Direction and Programs Divide Programs Among Members Collect Real Time Data Completed Work Current Work Future Work

References Mkt.html y.asp?productid= &xs=r&SID= &curr=USD

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