Actuate a Driveline Using Motions
You can apply a motion to a driveshaft directly, with an Ideal Angular Velocity Source or Ideal Translational Velocity Source block.
A motion source accepts a physical signal input and originates, from its mechanical conserving port, a mechanical connection line spinning or sliding with the specified motion.
The Simscape™ Driveline™ simulation solves for the torque or force carried by the spinning or sliding driveshaft, given its motion. Therefore you cannot also subject that same driveshaft to torque or force actuation.