Hi Nick, thanks for your answer. I built a lumbar spine model with 12 DGF muscle fascicles in this manner: (just as example) dgf = osim.DeGrooteFregly2016Muscle() dgf.set_max_isometric_force(79.58) dgf.set_optimal_fiber_length(0.1034) dgf.set_tendon_slack_length(0.0363) dgf.set_tendon_strain_at_one_...

I noticed that there is another forum for moco... So if any mod sees this you can delete the post as I opened another one in the moco forum.
This is the post: viewtopicPhpbb.php?f=1815&t=16766&p=0&s ... f516bf4353

Sorry about that!

Hello to all, I already posted this in the OpenSim forum, but I wasn't aware that there also is this forum! Sorry for any potential confusion.. I'm trying to calculate muscle forces for a specific motion with MocoInverse. I based my code on the examples I found in the docs (https://simtk.org/api_doc...

Hello to all, I'm trying to calculate muscle forces for a specific motion with MocoInverse. I based my code on the examples I found in the docs (https://simtk.org/api_docs/opensim/api_docs/). Unfortunately, when evaluating the results, I noticed that the muscle activation was the same as the force, ...

Hello Ton, first of all, thank you very much for this explanation. I am still new to the topic and appreciate your experience! For clarification: Both Moco and the Integrator are open-loop and since they are on different time grids, errors accumulate and the forward simulation becomes unstable? I ha...

I noticed that this issue of diverging forward dynamics only occurs when there is gravitational force turned on. I ran the whole process (obtaining torques from moco, feeding those torques in the FD) without gravity and it went smoothly and the error between the first predicted kinematics and the on...

Hello, for me this helped:
I guess you are using windows...
I had to add these two lines before every opensim import...

import os
os.add_dll_directory("C:/OpenSim 4.4/bin")

"C:/OpenSim 4.4/bin" could be different depending on where you installed Opensim

Quick update: Now, the forward sim results look ok(ish) until about 1.4secs (total simulation time 3s). I made a mistake in the model, and basically wrong controls where assigned to an actuator. However, I still not understand why the state values diverge so much after 1.4secs. Could anyone help me?...

Hello, I'm trying to verify some Moco outputs that I receive when running a predict study on my model. While the results from moco appear to be correct and also the visualization is nice and smooth, I get really weird (much higher) results for my states in the forward simulation. Also the visualizat...