how to scale MoCap_LowerBody


I am experimenting on some functions in AnMMRv1.6, MoCap_CowerBody.any. The tutorial itself (Making things move. using real data) demonstrates how to optimize the anthropometrical parameters, marker locations and movements etc., and how to calculate muscle/joint forces. I want to scale this skeleton based on tibia length first. Should I make changes to tibia length in TrialSpecificData.any directly? If so how do I make sure the scaling is uniform to all bones? In tree-view, I also found Main.Studies.Scaling, which seems to be a reasonable starting point as well, but I am not sure how to do it.

Thank you!


To be more specific, I wonder if this MoCap_LowerBody model uses AnyMan.any or AnyManUniform.any? Currently I am able to adjust the size by: TriaSpecificData.any -> Antropometrics -> BodyMass and BodyHeight. But for my case, I have the tibia length and average BWI of a group. I assume I can do a global scale using mean BodyMass and BodyHeight, then calculate scale_factor = my_tibia_length/default_tibia_length (0.4120814), and multiply all other size parameter by that scale_factor. Does it sound reasonable?

Thank you very much!!

If you use Motion Capture to drive the model, the body model will always be automatically scaled according to the recorded subject.

You have to give a guess on the segment lengths, but then, the system will calculate/optimize the segment lengths according to the recorded MoCap files.

If you have parameterized models, like the standing model, the bike model, kneebend or the boxlift model you can scale them to match pretty much any antropometry.

Thanks Amir. I mixed two problems together, which shouldn’t appear in the same situation.