Coordinates Visualization

[Daniel Iordanov]

Hello, I am trying to modify some OpenSim models for integrating them with C++.

My aim is to simplify a model, so when it is executed through C++ I can visualize only some of the coordinates of the whole model for an IK and ID process.

My question is if it is there any way to hide a coordinate in the Coordinate window? I have thought about removing the undesired coordinates in my model, for which I specify and modify them from CustomJoint to WeldJoint.

An example to explain myself better. For example, by default in a lower limb model I have coordinates that define 3 rotations for hip, 1 for knee and 1 for ankle. What I really want is to be able to visualize only the knee coordinate in the Coordinate Window and the others to be hidden or unexisting. Is there a way to do that? Hide in some way the visualization of coordinates that are not interesting for me?

Thank you very much.

Best regards,
Dani

[Dimitar Stanev]

This can be done only through welding the joint. In this case you are removing the coordinates of the joint. For simulation you can lock the coordinates, but this will not remove them from the model.

[Daniel Iordanov]

Thank you for the answer Dimitar.

After performing the coordinates removing by defining WeldJoints among joints I have faced a new problem.

In my case I was interested in removing all the coordinates except 3 defining the torso movement: lumbar extension, lumbar rotation and lumbar bending. My problem is that I already have the model with only 3 coordinates but when I visualize it in OpenSim and change the value of these nothing is moving in the visualizer.

Is there a limit of WeldJoints that can be defined in the model?
Concerning the topology view, it could be that the model is not answering because I have converted the ground-pelvis joint from a CustomJoint to a WeldJoint? (I was not interested in pelvis tilt, list, rotation and translations)

Thank you.

Best regards.