Knee flexion angle output

Dear AnyBody guys,

I have a question regarding knee flexion angle output. I run a model of hopping, and try to get the output from : selected output. From there we have the range of knee flexion output was quiet strange. It ranged between 30 to -90 degree of flexion. Can somebody explain how can we get negative value of knee flexion angle? how to read that? and even if it is negative, why is the knee over extension angle reached until 30 degree, for normal people, I think that is quiet strange position.

I attach the model.

Thanks for your help

Kindest Regards

Dear Wibawa,

I’m not sure which value you have seen from ‘SelectedOutput’ folder.
But that folder contains some joint reactions and moments, not angle.

You should see the following term:

The angle unit is radian.

Best regards,