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Hello,

I'm trying to scale a model and later do an IK analysis. I have a problem on the scale procedure, when i run the scaling tool the pelivs does not positionate correctly. Then, when i load the IK the pelvis is corretly positionated at some point of the movement but wrong at others. I have tried this .trc file in other model with the same marker set and it works, so i don't think is the .trc file itself.

Could anyone orientate me to repositionate the pelvis please?

Hard to tell without seeing the data/model itself, but two common causes of this problem are:

1) your model's pelvis_* joints (_tx, _tx,...) are locked and so the scale algorithm isn't being "allowed" to move the pelvis to the right place, or

2) the joint limits on the pelvis_tilt/list/rotation are too restrictive. For example in my Rajagopal-derived model, those rotation limits are +/- 90 degrees. That's fine if my subject was facing forward (down the +X axis in the lab) during the standing calibration, but if they were facing backwards I'd be in trouble. You can either adjust the limits, rotate the model, or rotate the marker data to fix this.