Behaviour of vel_integrator_torque when input_pos updated

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1

I have a question on the behaviour of vel_integrator_torque when input_pos is updated when doing position closed loop control in the passthrough input mode.

Does updating the input leave the vel_integrator_torque at the same value or does it cause it to be rest to 0?

We have to move the motor a fixed amount in two directions. To get to the correct value at position A and hold it at steady state, the vel_integrator_torque is positive. To get to the correct value at position B and hold it at steady state, the vel_integrator_torque is negative. When I change the input to position B, does the vel_integrator_torque have to be unwound all the way from its A value to its B value, or does changing the position mean it only needs to unwound from 0 to its B value?

2

Updating does not change the vel_integrator_torque – however given a generally precise encoder, this should update quite fast. Typically, you want your vel_gain to be doing as much of the error correction as possible, versus vel_integrator_gain.

One other solution would be to provide a torque feedforward equal to the amount to hold the motor at whatever given position.