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Gunter Siegmund
03-24-2003, 06:30 AM
Greetings...



The onset of movement is often estimated from biomechanical data using one of the following techniques:

a) the time at which a signal reaches a threshold (usually based in some way on the noise level in the pre-movement signal), or

b) the time at which a signal last crosses through zero (or some other baseline value) before the movement is clearly in progress.



We are attempting to quantify the bias introduced with these techniques for different transducers, movement rates, etc. and have the following questions for the group:



1. Are there other techniques that we should also consider?

2. Are there existing articles/references/sources that develop or evaluate techniques for estimating movement onset?



Our search of the biomechanical literature, the biomch-l archives and the web has yielded no primary sources for these techniques, only many examples of their use. A review of a number of signal processing books has also yielded nothing.



A summary of responses will be posted if there is sufficient interest.



Thank you,

Gunter

__________________________________________________ _____

Gunter Siegmund, Ph.D., P.Eng.
gunters@maceng.com

Adjunct Professor
School of Human Kinetics
University of British Columbia, Vancouver, BC, Canada
http://www.hkin.educ.ubc.ca

Principal
MacInnis Engineering Associates
11-11151 Horseshoe Way, Richmond, BC, Canada, V7A 4S5
http://www.maceng.com

office: 604 277 3040
fax: 604 277 3020
tollfree: 800 565 3040
__________________________________________________ _____

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