Hello.
I ran into this issue while trying to run inverse dynamics on a model. A little background:
I am currently trying to model an infant on opensim, and so I used marker based scaling from motion capture data to scale the GAIT2392 model to a reasonable scale to represent the infant. Since force plate data was unavailable, I created my own (although it is very inaccurate, I agree) to represent just the weight of the infant just to get preliminary results. When running the inverse dynamics tool, however, the GRF from the force plate data is displaced from the infant model. I believe this is causing results that do not make sense in terms of moments calculated.
I wanted to post on here and ask if anyone has had similar issues, or a solution when applying made up force plate data to a model. Thank you very much in advance.