We at the motion lab at Childrens Hospital L.A. are noticing issues in Vicon
Workstation regarding knee and ankle width measurements in "Subject
Measurements" effecting calculated joint centers of the knees and ankles in
an unpredictable way. We are having a hard time finding a definite pattern,
but sometimes changing a measurement after static processing, say left knee
width, followed by reprocessing, we notice any one of the following: the
left ankle joint center is affected, the opposite knee joint center is
affected, both ankle joint centers are affected, nothing is affected, or the
correct joint center is affected.

The stick figure in workspace as well as exported 3-d data reflect these
behaviors. Reconstructing between static reprocessing, saving, reloading
processed data, and opening and closing trials all seem to have an affect on
the outcome of which ankle joint centers are affected by which measurements,
but the exact pattern does reveal itself to us.

In any case, if anyone has experience with the matter and can comment, we
would much appreciate your input.

Greg Stanczak
Childrens Hospital of Los Angeles