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Good afternoon!

When I starded work in OpenSim, I found a difficulty, because after I make scale and adjust model, the bone components disappear in my actual model.
Does anyone know why this happens?

thank you

Hi Anderia,

If you have OpenSim 3.0 installed on a fresh machine, this should not happen but if you had an earlier version installed, then this could be an issue because of preferences that are persistent across installations. In version 3.0 we changed to use the absolute path to the Geometry folder under the install directory instead of using relative path as we did in the past (as more robust). Please follow the instructions on the upgrade notes here
http://simtk-confluence.stanford.edu:80 ... penSim+3.0

and you should not run into the disappearing geometry issue again.

Best of luck and please let us know how it goes,
-Ayman

Hi Aymanh,

I have some kind of a similar problem as Anderia!
When I try to scale my shoulder model, the thorax, clavicle and scapula completely disappear. The humerus gets slightly abducted. The radius and ulna seems to be okay [if humerus wasn't abducted]. Finally, the hand completely disappears as well.
One special thing about this model is that it uses ghost segments (segments between segment without any bones geometry attached to them) [this model is derived from the Holzbaur (2005, Standford VA Upper Limb Model)]

If you are aware of this kind of problem, I could enjoy some help!

I am using OpenSim 3.0.1 and I double checked the settings (preferences/Geometry path) and it seems to be okay!

Regards

Dear Ayman,

Thank you for viewing my email. I am a new user of OpenSim. Now I have a question during doing my work. I use the Gait2354 model, scaled it, and calculated the IK of one of my file (walking.trc), Actually, in this .trc file, certain marker (L.Acromium) is missing for the first frames (no gap-filling). In my expectation, there should be something wrong during doing IK, however, the IK succeeded. So I am wondering is OpenSim capable of gap-filling? Isn't it necessary to fill all gaps of one trial before using it in OpenSim? Thank you very much!

aymanh wrote:Hi Anderia,

If you have OpenSim 3.0 installed on a fresh machine, this should not happen but if you had an earlier version installed, then this could be an issue because of preferences that are persistent across installations. In version 3.0 we changed to use the absolute path to the Geometry folder under the install directory instead of using relative path as we did in the past (as more robust). Please follow the instructions on the upgrade notes here
http://simtk-confluence.stanford.edu:80 ... penSim+3.0

and you should not run into the disappearing geometry issue again.

Best of luck and please let us know how it goes,
-Ayman

Shuyang-

IK is conducted at each point in time, independently. If a marker value is missing at that time point, it is not added to the IK equation; http://simtk-confluence.stanford.edu:80 ... esEquation

Cheers,
-james