Hi all, The simulations that I am trying to re-run with DGF Muscle in OpenSim 4 are walking down a slope at -6 deg and walking on the level ground (0 deg), which were previously published at: https://www.sciencedirect.com/science/article/pii/S002192901630834X . The original study ran CMC with Thelen...

Hi all, As suggested by Nick, I plotted out the muscle-tendon length of Semimembranosus in the failed CMC trial (see the attached pic below; the output log of this trial was posted in my previous post). The Semimembranosus is the muscle that caused the failure of CMC. The MT lengths are about 0.347 ...

Hi John, When you replaced the right vasti muscles, did the CMC go through initially when there were warnings about exceeding maximum contractile velocity and tendon buckling? I am wondering whether the warnings are related to the fail in CMC initialization. I can confirm that the DeGrooteFregly mus...

Hi Nick, We are aware the small differences in the FLV curves in the DGF Muscle compared to the Thelen and Millard Muscle. This is the reason that we would like to re-run some CMC trials previously done with the Thelen Muscle. With regard to your suggestion of plotting muscle fiber lengths and veloc...

Hi all, Thanks for all your testing and thoughts. Here are a few things that I would like to add. To Ross' first comment. The reserve and residual actuators were included in the model I tested, with which the CMC could not initialize when muscles are replaced by DGF Muscle. The same model with Thele...

Hi John, Thanks for sharing your results. How many muscles were the DGF Muscle in the CMC simulation you ran? Were they only the three heads of vasti? I have been able to get CMC to run in the simpler models (Gait10dof18musc and Gait2354_Simbody) coming with the OpenSim4.3 installation with all musc...

Hi, It has been more than a year since this discussion started. Since the Moco is officially in OpenSim and explicit tendon compliance is the default option, I assume that the two issues mentioned in Nick's previous post should have been resolved by now. So, I wonder whether there is an definitive a...

When I am exporting tendon force multiplier in the DeGrootFregly2016Muscle, I get NANs. Does anyone know why? Thanks! import org.opensim.modeling.* DGF_model = DeGrooteFregly2016Muscle(); DGF_tendon_osimDataTbl = DGF_model.exportTendonForceMultiplierToTable(); Example output shown below: time tendon...

When I am exporting tendon force multiplier in the DeGrootFregly2016Muscle, I get NANs. Does anyone know why? Thanks! import org.opensim.modeling.* DGF_model = DeGrooteFregly2016Muscle(); DGF_tendon_osimDataTbl = DGF_model.exportTendonForceMultiplierToTable(); Example output shown below: time tendon...

I have seen the MOCO user guide, discussions in this forum and papers (Miller 2021 PeerJ) that suggest replacing other muscle models with DeGrooteFregly2016Muscle in order to work with MOCO. The reason for this is that DeGrooteFregly2016Muscle has all characteristics (FL, FV curves) C2 continuous (t...