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Should I remove Coordinate Limit Forces for Static Optimisation?

Posted: Mon Jul 12, 2021 6:13 am
by nicolasnie
Hello everybody,

I would like to use the "Upper Extremity Dynamic Model" (https://simtk.org/projects/upexdyn) with the Static Optimization algorithm to calculate Joint Reaction Forces (using Joint Reaction Analysis).
However, as I understand, there are Coordinate Limit Forces (CLFs) present in the musculoskeletal model. These are used to enforce the limits when using a forward dynamic simulation like CMC (right?).

As I want to use Static Optimization instead of CMC, I should be able to simply remove the CLFs from the model and get proper muscle forces, as well as JRFs.

Could you confirm this assumption?
- A big thank you in advance!


(Let me know if you need more input!)

PS: Also, the CLFs would make the calculated JRFs obsolete, as OpenSim would "include their contribution as part of the resultant joint load" (https://simtk-confluence.stanford.edu/d ... s+Analysis). Is this correct as well?

Re: Should I remove Coordinate Limit Forces for Static Optimisation?

Posted: Tue Jul 13, 2021 1:32 am
by nicolasnie
... or is it possible, that the model I'm using is only compatible with CMC/forward dynamics?