You can run a MuscleAnalysis in the GUI or in Python ( https://opensimconfluence.atlassian.net/wiki/spaces/OpenSim/pages/53088479/How+to+Use+the+Analysis+Tool , https://simtk.org/api_docs/opensim/api_docs/classOpenSim_1_1MuscleAnalysis.html ) which will generate a file containing the fiber force for...

Does this mean that P=C (see image B) for this joint? Yes. This is true for most joints, a notable exception being the knee in models like gait2392 (which is defined as a CustomJoint with nonzero translations between the origins of the parent and child frames). It might be helpful to visualize the ...

Some general ideas can be found on the following pages of the documentation: - Collecting Experimental Data -> Collecting Marker Data ( https://opensimconfluence.atlassian.net/wiki/spaces/OpenSim/pages/53089986/Collecting+Experimental+Data ) - Getting Started with Scaling -> Best Practices and Troub...

Please take a look at OpenSense (https://simtk.org/projects/opensense). Once you have the kinematics of the model, you could write a script to pose the model, store the location of each marker with respect to ground, and iterate over all time points.

How do I know when my actuators are too high? One might define an unacceptably large amount of error as being an amount of error that would affect the answer to the research question. This likely depends on the quality of the data, the model and calibration process, what movement you're investigati...

You could place markers on the points of interest, then run a forward dynamic simulation where you apply the activations (as excitations), disabling activation dynamics if you wish. You can use the Output Reporter ( https://simtk.org/api_docs/opensim/api_docs/classOpenSim_1_1OutputReporter.html ) to...

It depends on which OpenSim Tool you are using. If you're running Inverse Kinematics, for example, you can set the report_marker_locations property to True. Another method is described in Forum Topic 16938 (viewtopicPhpbb.php?f=91&t=16938).

The getComponentsList() method does not take an argument; it returns a list of all components and does not downcast. Here is an example use case (from test_access_subcomponents.py): num_components = 0 for comp in model.getComponentsList(): num_components += 1 There do not seem to be Python bindings ...

The error is of the form "GCVSpline: there must be # or more data points." This string can be found on line 99 of GCVSpline.cpp ( https://github.com/opensim-org/opensim-core/blob/ae4fcd2076cce6de9ca3d9c5a854cc72fc9b7841/OpenSim/Common/GCVSpline.cpp#L99 ). Presumably you are requesting a quintic spli...

what should i do to add the conditionnal pathpoint to the pathpointset of the muscle?

I think it would be something like this: I've used upd... methods here but the get... versions should work equally well in Matlab.