During machining the high accuracy non-circular part, normally the trajectory of non-circular part profile is generated, and then the fast response linear servo motor drive the cutting tool to do reciprocating moving, and control the cutting tool synchronously with the spindle. The control accuracy of the non-circular part trajectory is critical to affect the non-circular part CNC machining. Based on the periodic features of non-circular profile trajectory, the control algorithm which is hybrid control of P...