Much thanks to all that have responded so far. In reading the replies, I realized I should have made my question clearer. I have been given a data set of human subjects standing and walking on a treadmill recorded with a Phase Space optical tracking system. The data has 6 degrees of freedom information about each active marker (x, y, z, yaw, tilt, roll all relative to a fixed origin) and there is only one active marker on each limb segment (shank, thigh, pelvis, trunk, upper arm, forearm, head). I am looking for code (not commercial software) that would provide me with a method of deriving joint angles from the marker data. I do not have more than one marker on each segment. I am familiar with many software programs available, but do not know of any open source or freeware software that would allow me to process such a data set.

Some of the options mentioned in the replies to date that I am looking into:

http://www.innovision-systems.com/Products-MaxMATE.aspx

http://isbweb.org/software/movanal/kinemat/index.html

http://www.bodymech.nl/

http://www.kiboho.co.za/GaitCD/gaitbook.htm

KineMat package for Matlab (on isbweb.org)

www.internationalshouldergroup.org

Visual 3D (http://www.c-motion.com/ )

Thanks again to all that have replied.
df


Dan Ferris, Ph.D.
Associate Professor
Division of Kinesiology
Department of Biomedical Engineering
Department of Physical Medicine and Rehabilitation
University of Michigan
http://www-personal.umich.edu/~ferrisdp/

currently on sabbatical at:
Institute for Neural Computation
UC San Diego
(858) 534-9662

ferrisdp@umich.edu