simtk.org

Hello,

I am attempting to scale a model (based on Caruthers full body model 2016), and I'm having some issues with the scale tool stalling and OpenSim keeps giving me an "unexpected exception." There is a snip attached of the settings that I'm using in the scale tool, as well as the "exception" popup that happens when I try running the scale tool. I also attached the printout of the messages tab in OpenSim, as well as the scale factors and static pose weights tabs in the scale tool.

I am fairly confident that my .trc and .mot files are okay, and the time points that I'm averaging measurements and markers between have numbers for data (no NaN's or anything for any markers during any of the .trc and .mot files). And I'm fairly confident that all markers are labeled correctly (including the heavily weighted ones). So I am thinking that there is some problem with how my model is structured in my .osim file? Any advice or guidance on how to address this java exception would be appreciated. (My model is slightly different from Caruthers 2016 full body, so I am guessing that I structured something poorly in my customized model. But would like to confirm that I am using the scale tool correctly.)

If any other background info would be helpful, please let me know and I'd be happy to add more snips/attachments.

Thank you!
Katie

Hi Katie,

The stack trace of the exception suggests this has to do with failing to assemble the model rather anything to do with the data or data-processing. If the model has constraints it's likely that the scaling step caused them to be violated before even trying to place the markers on the model. I'd suggest you uncheck the "adjust model markers option", disable some/all constraints, do the scaling then engage the constraints to see what breaks. The scaling process doesn't have a generic method to handle constraints so you may need to adjust those on your own.

Please let us know how that goes,
-Ayman

Hi Ayman,

Thanks so much for the quick reply! I'll try this and follow up with how it goes.

Thanks!
Katie

Hi Ayman,

This worked! I found the constraint that is getting violated when I try to scale.

A weld constraint in my model is violated when I try to scale because the location of the weld is not scaling with the bodies. I tried scaling the location of the weld by the same factor that I am scaling the bodies with, by editing the "scale factors" within the weld constraint of the model (screenshot attached), but this doesn't seem to scale the location of the weld because I'm still getting a model assembly error in OpenSim.

Do you or anyone else following this thread have advice for how to scale the weld location? Happy to provide more details of things I've tried, if that's helpful for background

Thanks!
Katie