View Full Version : Question about calculating COP without Moment data

06-16-2009, 10:52 PM
Hi there,

I am trying to process standing posture data collected from two
adjacent AMTI forceplates. One foot was placed on each forceplate,
however body weight may not have been equally distributed. Our system
was set-up so that the X-axis is medial-lateral (+X to the left), the
Y-axis is anterior-posterior (+Y pointing straight ahead of the
subject) and the +Z direction is down. We have force and moment data
for all three axes for each of the forceplates. Unfortunately, a
loose connection has rendered some of our Moment-about-Y data for one
of the forceplates unusable (the forceplate under the subject's right
foot). I was just curious if anyone knows of a way in which we can
calculate the center of pressure for the right foot without actually
having Y-moment data for that foot? We can assume that the test
subject is a rigid body with rotation about the ankle. All other data
channels are in tact.

Thanks so much in advance for any suggestions,


Katie Mountjoy, M.Sc.Eng
Laboratory Technician
Motor Performance Laboratory
School of Rehabilitation Therapy
Queen's University
Kingston, ON Canada