Hi again,

The classical inverse dynamics now works perfectly on my sit-to-stand model.

Thanks again.

But now, when I run the muscle recruitment analysis, I get:

ERROR(OBJ1) : C:\Documents and Settings\Jean-Olivier

Racine\Desktop\LIO\Anybody\Repository.6\ARep\LIO\STS Test

4\MuscleStudy.any(1) : ‘MuscleStudy’ : Muscle recruitment analysis

failed, simplex solver reports that solution does not satisfy all

constraints.

My questions:

- From the (Damsgaard, Rasmussen, Christensen, 2001, ASME) article on

the min/max optimization criteria, I see that the constraints used for the

min/max criteria are quite classical and are 1) the dynamics equilibrium

equations and 2) the muscle pull constraint. Is there a way to know which of

these two constraints is not satisfied by the simplex solver? I know the

simplex solver, in essence, doesn’t naturally allow it. but we never know. - I tried running the analysis with 4 different trials (data set) and

in each case, the error appears exactly at seat-off. Knowing that currently

I do not include the seat force but only the ground force, could that be the

problem? If it is, what interactions within anybody explain that problem? I

am surprised that the problem does not appear right from the beginning, when

the seat force is missing, and not when the seat force disappears

(seat-off).

I uploaded the model to the group. Filename is JeanOlivier2.rar.

Thanks,

Jean-Olivier

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