Kinetically over-constrained mechanical system error

Main Forum
#1

I have created a simplified knee joint model for my project and I have been getting this error whenever I run an InverseDynamics operation.

"The muscles in the model are not loaded due to kinetically over-constrained mechanical system".

I have tried to remove the ligaments and some muscles but with no solution. What should i do?

Thanks.

#2

Please check that the drivers you have added to the model do not have the reactions switched on by mistake, the default is on.

This means that if you are driving e.g. a knee flexion with a driver on a kneeflexion dof it will add a torque reaction by default and the muscles will not need to carry this dof.

Please in the driver write e.g. (for a driver with one dof)

AnyKinEqSimpleDriver MyDriver ={
...
Reation.Type={Off};
...

};

This will ensure that the driver does not carry the load.

Best regards
Søren

#3

Thank you very much for the reply.

but now i have another error popping up which says.

Muscle recruitment solver : solver aborted after maximum number of line-search iterations

which now stops the solver.

#4

This error means that one or more DOF in the model can not be balanced by either muscles, ligaments or reactions forces.

Please try to add back again the reactions you removed one by one to reveal which DOF is causing the problem. Once you know which DOF it is you will need to evaluate the cause for it, e.g. lack of muscle being able to balance the DOF.

Please also see

Best regards
Søren

Best regards
Søren

#5

This topic was automatically closed 125 days after the last reply. New replies are no longer allowed.