Static optimization tool locking up at certain time-steps

[Tom Augenstein]

When I run the static optimization tool in the GUI, it will lock up at certain specific times and never achieve a solution. I checked both the IK and ID outputs to see if there were any larger accelerations at these times that the program was trying to match, but I couldn't find any. Also, I tried relaxing certain integration parameters like error to see if I could get the program to give me any answer, but that didn't work either. I'm filtering the input kinematic data at 6 Hz. In addition, I appended coordinate actuators at each unlocked joint.

I'm fairly confident in the accuracy of my model, but locking certain joints saves the program from getting hung up, so I'm not sure.

Does this problem sound familiar to anyone?

[Dimitar Stanev]

1) You can look at the message window
2) If the model has constraints they may cause problems

[Tom Augenstein]

1.) There is no message that is out of the ordinary. The program just won't continue, no error/warning messages.

2.) Thanks, I'll give that a try, although the constraints didn't trip up the IK or ID

[Erica Beaucage-Gauvreau]

Are the muscles in your model Thelen? It could be reaching a discontinuity?

Try switching to Millard Muscle and see if it helps solving the problem maybe?