constraints do not apply in inverse dynamics

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dani mendez
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constraints do not apply in inverse dynamics

Post by dani mendez » Wed Jun 24, 2020 10:10 am

exo.png
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Hi, I am trying to join the following exoskeleton to the arm, to achieve this I have used a weldconstraint to close the system. The problem is that when doing the inverse dynamic study, the weldconstraint is omitted, obtaining unexpected results. Is there a way to get the resolution to work? In the next post (viewtopicPhpbb.php?f=91&t=11925&p=0&sta ... 0f78d96154) I think there is talk of a possible solution, but I do not finish understanding how to apply it. Any help is welcome.
Thank you

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Dimitar Stanev
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Re: constraints do not apply in inverse dynamics

Post by Dimitar Stanev » Mon Jun 29, 2020 12:19 am

Hi Dani,

Typically, these type of problems are solved using the forward dynamics approach, because ID works only for unconstrained systems. In your case, you can use the CMC tool. After executing CMC you can calculate the joint moments due to all actuators (e.g., muscles and motors) using the AnalyzeTool and MuscleAnalysis. Also, it is possible to append the muscle analysis in the CMC .xml setup file and do this directly in one step.

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dani mendez
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Re: constraints do not apply in inverse dynamics

Post by dani mendez » Fri Jul 03, 2020 1:14 am

Thanks Dimitar, Could it also be solved using MOCO?

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