detect whether the user is holding the endeffektor to dynamically switch PID config

[boeckhoff]

When the user is not holding the endeffektor, we need to actuate the motors with way less power to reach a target, otherwise we get a lot of oscillation and endeffektors overshooting the target position.

Wheter the user is holding the endeffektor or not should be relatively easy to determine by looking at how much torque the motors are exerting in relation to how much the endeffektor is moving.

[JotaroS]

BTW I think this is hardware-specific issue.
If we change the motor to capstan / geared motor, we will have much control over torque against system physical delay.