Clamping pelvis_rotation

[antoinefalisse]

@suhlrich why not setting this to false: https://github.com/stanfordnmbl/opencap-core/blob/main/opensimPipeline/Models/LaiArnoldModified2017_poly_withArms_weldHand.osim#L3182

When the subject is turning around, IK fails. You get non-meaningful values if set to false since it can exceed the range, but at least the motion is decent. Other option is to increase the range, as we did for the upper extremities.

[suhlrich]

I assume it is regularized by default cuz the initial guess is prob 0? So for normal camera-facing motions, will we consistently get 0?

[suhlrich]

But yes, it seems we should unclamp