Estimation body segment

[Sandra Salvador]

Good morning,

I am working with OpenCap and would like to compare the data with 3D marker-based MOCAP systems. How do you estimate the body segment parameters in the OpenSim model?

Thank you very much,

Sandra Salvador

[Matt Petrucci]

Hi Sandra,

All the body segment parameters are stored in the .osim model file. You can either view them in a text editor, or if you open the model in OpenSim, you can inspect them in the GUI.

Hope this helps,

[Sandra Salvador]

Yes, it makes sense!

Thank you very much!!

[Sandra Salvador]

Hello again!

I can't find which markers you use to define the body segments in the OpenSim model.
Do you know If there is any specific paper or document with this information??

And one more question.
Is OpenCap able to track a specific player during a team sports match (handball, football, basketball...)?

Thank you very much,

Sandra Salvador

[Matt Petrucci]

Hi Sandra,

If you select each marker in the GUI, you'll see what body it is attached to (see attached image, /bodyset/femur_r). You can also see this if you open up the .osim file.

OpenCap would struggle to track one player during a match, unless the person of interests appears the tallest through the whole trial.

Hope this helps,

[Sandra Salvador]

Yes, Thank you!!