Scaling problem

[Léo Denouël]

Hi,

I'm looking to model the execution of a Timed-up-and-go by patients.

To do this, I'm using a model of 30 markers that I've scaled to the patients' marker coordinates.
The problem is that the scaling doesn't work very well: my pelvis is constantly tilted to the right (see photo).
I tried other models, I tried manually to correct the posterior markers of the pelvis by modifying them to correct this tilt, it is better, but it does not correct the problem on all patients.
Inverse kinematics' results gives me an unstable pelvis that moves too much.

Do you have any ideas for solutions ?

Thanks

[Mahshida hamid]

can you share the marker file and the trc file, It will give a better idea of the said problem.

[Umer Huzaifa]

Hi there,

For anyone who is still trying to figure out these issues, there most likely is a misalignment of the experimental data in TRC and the OpenSim Coordinate convention. Since you cant change the convention in OpenSim, you will have to rotate the collected data appropriately.

I hope this helps.

Umer

[Mohammadreza Rezaie]

Hi, this may help: https://simtk-confluence.stanford.edu:8 ... leshooting