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Python Hook

When using the Force-Dependent-Kinematic function, how many times is this external function evaluated: with each iteration of the FDK solver or only once at the beginning of the quasi-static calculation of the kinematics?

To solve the Force-Dependent-Kinematics, the forces are calculated for each guess for kinematic positions. So since your python function is used to calculate forces based on positions, it should be evaluated in every iteration step (we are not aware of anything different).