OpenSim 4.0 InverseKinematics resets joint reverse

[ANDREW LAPRE]

Hi,

I'm having trouble with the InverseKinematicsTool using OpenSim 4.0. I'm running everything through MATLAB 2014a.

The model is modified in my script, saved, reloaded and initialized before calling the tool so that the model format is up to date for version 30505. I can check get_reverse on the specific joint just before running the tool, and it returns "1". After the tool runs, I check it again and it returns "0". The script works fine with past versions of OpenSim, however I need to use 4.0 so that I can modify the source code and still have access from within MATLAB (the source code on the SimTK website doesn't include the necessary bindings for MATLAB scripting)

Do any of the 4.0 developers know why this is happening? I've dug through the source code quite a bit and can't figure it out.

Thanks in advance,
-Andy

[Christopher Dembia]

Ajay Seth would know more, but version 4.0 builds the multibody tree in a very different way. It uses the Simbody multibody tree builder, which I think decides whether or not the joint is reversed. I'm not sure, though.

This issue would be better suited to a GitHub Issue. Would you be willing to create an Issue on GitHub for this? https://github.com/opensim-org/opensim-core/issues/new

[ANDREW LAPRE]

Yes, I can do that.

Thanks for the response, I knew this wasn't exactly the best place to ask but have been stuck for a couple weeks. I'll submit an issue now.

Thanks!

-Andy