A kind of the pulse control mode, the drive and motor closed loop, but not to the numerical control system, the feedback device, in a sense, can open loop control called the servo control.

The pole-placement namely is to make poles of closed loop of system just at positions of a group of desirable poles by selecting state feedback matrix.

The method sets system disturbance within the feedback gain matrix f, which can be computed by iteration, in order to make the closed loop system optimum.