By Topic

Lower extremity angle measurement with accelerometers-error and sensitivity analysis

Sign In

Cookies must be enabled to login.After enabling cookies , please use refresh or reload or ctrl+f5 on the browser for the login options.

Formats Non-Member Member
$33 $13
Learn how you can qualify for the best price for this item!
Become an IEEE Member or Subscribe to
IEEE Xplore for exclusive pricing!
close button

puzzle piece

IEEE membership options for an individual and IEEE Xplore subscriptions for an organization offer the most affordable access to essential journal articles, conference papers, standards, eBooks, and eLearning courses.

Learn more about:

IEEE membership

IEEE Xplore subscriptions

3 Author(s)
A. T. M. Willemsen ; Dept. of Electr. Eng., Twente Univ., Enschede, Netherlands ; C. Frigo ; H. B. K. Boom

The use of accelerometers for angle assessment of the lower extremities is investigated. This method is evaluated by an error-and-sensitivity analysis using healthy subject data. Of three potential error sources (the reference system, the accelerometers, and the model assumptions) the last is found to be the most important. Model calculations based on data obtained by the Elite video motion analysis system showed the rigid-body assumption error to be dominant for high frequencies (>10 Hz), with vibrations in the order of 1 mm resulting in errors of one radial or more. For low frequencies (<5 Hz), the imperfect fixation of the accelerometers combined with a nonhinge-type knee joint gave an error contribution of +or-0.03 rad. The walking pattern was assumed to be two-dimensional, which was shown to result in an error of +or-0.04 rad. Accelerations due to rotations of the segments could be neglected. The total error computed for low frequencies (+or-0.07 rad) is comparable to the experimental difference between the current and the reference system.

Published in:

IEEE Transactions on Biomedical Engineering  (Volume:38 ,  Issue: 12 )