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Dear OpenSim users,

I am trying to use the thoracoscapular model. However, when I scale the model in the GUI, the humerus and radius are not attached anymore in my scaled model. Does anybody know how to fix this? I have unlocked all coordinates of the original model. Also, when I scale this model through Matlab I get the following error after initializing the system or using the scaling tool:

Body 'scapula' not connected by a Joint.
A FreeJoint will be added to connect it to ground.
Java exception occurred:
java.io.IOException: Attempting to assign an invalid SimTK::MobilizedBodyIndex
In Object 'cp_in_clavicle' of type PhysicalOffsetFrame.
Thrown at PhysicalFrame.cpp:73 in setMobilizedBodyIndex().
at org.opensim.modeling.opensimSimulationJNI.Model_initSystem(Native Method)
at org.opensim.modeling.Model.initSystem(Model.java:848)

Is there a way to fix this in the model?
It also says that the model is not recognized:Object::newInstanceOfType(): object type 'ScapulothoracicJoint' is not a registered Object!
Object type ScapulothoracicJoint not recognized

Thank you in advance for any advice.

Kind regards,

Maud

Dear Maud,
I know that your question is a bit old but maybe I can try to help you (or help others who are in your same situation).
I am also scaling the thoracoscapular shoulder model, both in the GUI and in Matlab, and I haven't run in your issue. Which setup file were you using for the scaling? Were you using the same markerset that comes by default on the model itself?

I really hope that you were able to solve this problem, and in case it would be great if you could post here what was going wrong!

Best regards,
Italo

Dear Italo,

Sorry to bother you. I have some questions for the marker in this model which I want to consult with you.
How could you make sure the position of marker "gu", it seems like this marker is in the humerus bone.
And how do you attach marker "centelbow"? Did you attach EpL and EpM marker during experiment and calculate centelbow marker position later?

Best regards,
Jiale

Dear Jiale,
note that I was not involved in this study, I am just using the model and the data myself. So, I was not present during the experiments and digitalization of the markers. However, in general, you are right when you say that the position of certain markers has been calculated during the post-processing step, as they are physically impossible to place (like the "centelbow" one). There exist some regression techniques that, given the position of a few bony landmark, can estimate quite accurately the position of other point of interest (such as the center of a joint, or particular points on the scapula). For what concerns the "gu" marker, I am not sure how it was tracked/retrieved.
I hope this helps!

Best regards,
Italo