Markers not aligned correctly in Inverse Dynamics & Marker Tracking simulation - MoCap model correction

Hello,

I am trying to improve/correct my MoCap model. In both marker tracking and inverse dynamics simulations, there remains a distance between the experimental and AnyBody marker pairs. At each running stride, this distance (mainly at the thigh cluster markers) is increased to a maximum at a certain point and then gets reduced. There remains a gap between other marker pairs as well. How can I improve my marker tracking and inverse dynamics simulation in this case? Please see the picture below (1 & 2).

In the optimization using the static trial (RunParameterIdentification), all these markers were properly aligned with each other. Please see the picture (3) below for the results after optimization. What could be the reason of this mis-alignment between experimental marker and AnyBody Marker pairs, even though I have obtained good alignment in the optimization? I have checked for loose markers, and this is probably not the case, since I have this issue with other subjects and most of the marker pairs in my model.

Your feedback would be highly helpful to improve my understanding of the model and the simulation. Thank you in advance.

Best Regards,
Arif

Hi Arif,

Have you tried to use a dynamic trial for the parameter optimization?, it might provide a better fit, in the dynamic trials. And secondly you are sure that you have setup the LoadParamterFrom correctly in the TrialSpecific.any file so that it is using the optimized values (it looks like this is done otherwise your errors would likely be larger :wink: )

Best regards
Søren