Abstract:In order to improve the machining accuracy and production efficiency, a method of interpolation control for ORAC NC lathe feed unit was described. According to the mechanical structure and the requirements of interpolation function of feed unit, with industrial PC as hardware platform and with Windows as software platform, “NC embedded PC” structure was used in hardware circuit, the interpolation control system of feed unit of machine tools was developed into a CNC system based on Windows environment, so as to realize the interpolation control to the lathe. The software program for circular interpolation and linear interpolation was written, and the interpolation control simulation of the ORAC lathe was realized.