[wireties]

Originally Posted by Ether

If you want position (or velocity) control of the CIM, you will have to have an appropriate sensor, and use that sensor to perform closed-loop control of the CIM. The CIM is not a servo; and it's not a stepper motor.

Entirely correct! If it helps this is how a common CNC is done these days. They use DC servo motors that are servo-ing on velocity and/or current. Usually this servo loop is hardware-based and built into the amplifiers that drive the motors w/ tach output. The system servos on position using external position sensors, optical scales and such. The position servo is done in software or (in a more expensive setup) in a FPGA or a dedicated computing engine of some sort.