Cosimulation, Motion view/Motion solve and Simulink/Matlab

Hi Jasmin-

One initial suggestion, make sure the MotionSolve model solves first without cosimulation.  

Also, you may want to try one of the co-simulation example/tutorial models (if you haven't already), just to make sure the workflow and software setup work (this would eliminate any potential issues with your modeling setup)

Best,

Chris

Hi Chris,

I checked that the MotionSolve model solves without the cosimulation and the tutorials for co-simulation worked fine.

Is it possible that the Plant_Input variables of the motions could be the cause? that they can't be differentiated two times?

best regards

Jasmin

I don't see a reason why you can't differentiate two times.  However, with some mechanical systems, 2nd derivatives can become noisy, or very discontinuous.  This may be the source of the issue.

Chris

The cosimulation does't run  though. I tried to  run the motionsolve model without the cosimultion to make sure that the model is fine. I used curves as Inputs and It worked in pure MS simulation because the curve points are interpolated with cubic polynomials that can form first and second time derivatives. However the convergence problem is still there. Could it be that the problem is caused by the use of  Angle sizes as Plant_Inputs for which no derivation information is available?

Jasmin

I guess it's possible.  At this point, there appears to be something specific in your model that's causing the issue.  I would take a step back, and try a simpler co-simulation setup.  Without seeing the model, and understanding the specific details, it's really hard to make useful suggestions.

One thing you can do while testing your model, is to create outputs that report what the solver variables are calculating what is being passed through cosimulation.  That way you can verify that what you expect to be passed to the cosimulaton has the correct scale, etc.

Chris