Inertial sensor-based knee flexion/extension angle estimation

Cooper, G, Sheret, I, McMillian, L, Siliverdis, K, Sha, N, Hodgins, D, Kenney, LPJ ORCID: and Howard, D ORCID: 2009, 'Inertial sensor-based knee flexion/extension angle estimation' , Journal of Biomechanics, 42 (16) , pp. 2678-2685.

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A new method for estimating knee joint flexion/extension angles from segment acceleration and angular velocity data is described. The approach uses a combination of Kalman filters and biomechanical constraints based on anatomical knowledge. In contrast to many recently published methods, the proposed approach does not make use of the earth’s magnetic field and hence is insensitive to the complex field distortions commonly found in modern buildings. The method was validated experimentally by calculating knee angle from measurements taken from two IMUs placed on adjacent body segments. In contrast to many previous studies which have validated their approach during relatively slow activities or over short durations, the performance of the algorithm was evaluated during both walking and running over 5 minute periods. Seven healthy subjects were tested at various speeds from 1 to 5 miles/hour. Errors were estimated by comparing the results against data obtained simultaneously from a 10 camera motion tracking system (Qualysis). The average measurement error ranged from 0.7 degrees for slow walking (1 mph) to 3.4 degrees for running (5mph). The joint constraint used in the IMU analysis was derived from the Qualysis data. Limitations of the method, its clinical application and its possible extension are discussed.

Item Type: Article
Themes: Subjects / Themes > R Medicine > R Medicine (General)
Subjects / Themes > T Technology > TJ Mechanical engineering and machinery
Health and Wellbeing
Subjects outside of the University Themes
Schools: Schools > School of Computing, Science and Engineering
Schools > School of Computing, Science and Engineering > Salford Innovation Research Centre
Schools > School of Health and Society > Centre for Health Sciences Research
Journal or Publication Title: Journal of Biomechanics
Publisher: Elsevier
Refereed: Yes
ISSN: 0021-9290
Related URLs:
Depositing User: Professor Laurence Kenney
Date Deposited: 23 Dec 2010 11:26
Last Modified: 15 Feb 2022 15:49

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