After Scaling the muscle attachment points do not lie on bones anymore

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Shivangi Giri
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After Scaling the muscle attachment points do not lie on bones anymore

Post by Shivangi Giri » Fri May 22, 2020 1:18 am

Hello,
After Scaling, the muscle attachment points are moved away from the bones. Is this expected behavior? If not, kindly tell me how to correct it.

Regards,
Shivangi
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Ayman Habib
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Re: After Scaling the muscle attachment points do not lie on bones anymore

Post by Ayman Habib » Fri May 22, 2020 1:03 pm

Hello,

The geometry/bones are used exclusively for visualization, so what matters really is where the path-points are located on the body, not where are they relative to the meshes. While this may be an indication of improper scaling (since uniform scaling of all bodies should leave all attachment points the same relative to the meshes), but by itself this is not a problem.

Hope this helps,
-Ayman

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Shivangi Giri
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Joined: Sun Jul 02, 2017 3:04 am

Re: After Scaling the muscle attachment points do not lie on bones anymore

Post by Shivangi Giri » Fri May 22, 2020 11:57 pm

Thank you Ayman for the clarification.
Regarding what you mentioned that it may be a case of improper scaling, these files are from Rajagopal et al. "Full body musculoskeletal model for muscle driven simulation of human gait" OpenSIM version 3.3, the original unscaled Rajagopal and scaled Rajagopal model.
Does this mean the original scale factors need to be changed for better scaling? Can I not rely on the files they have provided?

Regards,
Shivangi

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