A method for determining minimal sets of markers for the estimation of center of mass, linear and angular momentum
2009 (English)In: Journal of Biomechanics, ISSN 0021-9290, E-ISSN 1873-2380, Vol. 42, no 3, 361-365 p.Article in journal (Refereed) Published
A new method is proposed for finding small sets of points on the body giving sufficient information for estimating the whole body center of mass (CoM), as well as the linear momenta (LM) and angular momenta (AM). In the underlying model each point (whose trajectory is tracked by a marker) is a point mass: Hence the body is represented by a simple system of point masses. The first step is to determine the appropriate set of points and the mass of each point, which is assumed to be specific for the movement performed. The distribution of the mass to each marker is determined from training data for which the true (or reference) trajectories of the CoM, LM or AM are known. This leads to a quadratic optimization problem with inequality constraints. The use of the method is demonstrated on data from discus throw. Results indicate reasonably small errors, considering the magnitude of other error Sources, in CoM position (average magnitude of estimation error 1-2 cm), and moderate errors in AM (13-20% of peak Value).
Place, publisher, year, edition, pages
2009. Vol. 42, no 3, 361-365 p.
Motion analysis, Motion capture, Optimization, Momentum
IdentifiersURN: urn:nbn:se:kth:diva-32218DOI: 10.1016/j.jbiomech.2008.10.029ISI: 000263657600027ScopusID: 2-s2.0-58649093295OAI: oai:DiVA.org:kth-32218DiVA: diva2:409753
QC 201104112011-04-112011-04-112011-04-11Bibliographically approved