Control COnstraints CMC

[Christian Greve]

Dear OpenSim Team,

I am using CMC to compute muscle and ligament forces during gait. I am interested in the effect of adding EMG-based control constraints. So I add the EMG based control constraints in the CMC tool. The tool is finishing but there is no difference in the activations when I do or do not add control constraints.

Thinks I already checked:
1. The constraints do not resemble the original acitvations too much
2. I load the constraints file in the tool and do not manually adjust the excitations without saving and re-loading
3. The .xml file has the same structure as the example files provided in the tutorial, except for the default description.

Do you have any suggestion?

Kind regards

Christian

[Thomas Uchida]

The Messages Window may provide some useful information. You could also try comparing your files to those from an existing simulation that uses Control Constraints (e.g., https://simtk.org/projects/runningsim).

[Christian Greve]

Thank you.

Regarding the Messages window: the simulation finishes fine so I do not receive any error message. I also see no warnings concerning the constraints file.
Regarding existing files: I modify the output from a successful CMC solution.....so the file should be fine I guess. Also it has the same structure as the example files in for example the gait2354 folder.

Could it be useful to limit the constraints file only to those activations which I actually manipulated?

Regards

Christian