Angular displacement of torque wheel.
(<- (Wheel-Torque ?X)
(Dot (Basis.Vec (Reference-Frame Actuator-Base) 1)
(Applied-Torque Actuator-Base Torque-Wheel)))
(=> (Wheel-Torque $X $Y) (Time-Quantity $Y))
(=> (Wheel-Torque $X $Y) (Mechanical-Component $X))