Some key realization technologies for NC system based on STEP-NC

To overcome shortcomings aroused by G code in Numerical Control (NC) machine tools, a scheme for establishing STandard for the Exchange of Product model data-NC (STEP-NC) system was proposed. The scheme was divided into two parts: Control software and hardware. Control software with modularized design included five parts: Interpreting module, man-machine interface, task coordinator, axis group and axis module. Aiming at the object-oriented characteristics of STEP-NC program, layout of the manufacturing features was planned for unit path aggregation in interpreting module. Based on the unit path aggregation, other modules with finite state machine behavior model finally realized machining by controlling of servo system. For the hardware, an open architecture was used to adopt different products from different factories, which were connected by SERCANS bus. With machining testing, the expected machining features were realized, which proved that interpreting module was accurate and NC system was stable.