simtk.org

Hi,

We have collected various activities in the lab simultaneously with our Qualisys mocap system and would like to compare the two data sets.
We use Visual3D for processing our Qualisys data and wondered if it is possible to import the data from OpenCap into Visual3D?

Many thanks
Matt

Caveat: we don't use Visual3D here, so I'm not an expert there.

You likely could bring in the marker data from OpenCap into Visual3d just like you would marker data from a marker-based mocap system. This will likely lead to poor kinematic results, since OpenCap benefits from the constrained musculoskeletal model in OpenSim, and I believe Visual3d uses 6DOF joints. We did not design the OpenCap marker set for 6dof joints.

To validate OpenCap against Qualysis, I recommend processing both in OpenSim using the same musculoskeletal model similarly to how we did it in this paper (https://www.biorxiv.org/content/10.1101 ... 7.499061v1). This would involve scaling a model and running inverse kinematics using your Qualysis marker data and the OpenSim model distributed with OpenCap. The model and setup files that we use for this in OpenCap are here https://github.com/stanfordnmbl/opencap ... imPipeline.