Real-time CNC Tool Path Generation for Machining IGES Surfaces

A real-time CNC tool path generation algorithm has been developed for machining IGES surfaces. IGES-based CAD data files can be directly inputted to the CNC system and the tool paths generated in real time can be passed to a motion controller during cutting via a Multibuss II backplane structure. The development of such a real-time tool path generation method has eliminated the need for a tradeoff between the desired surface accuracy and the required memory size for storing off-line generated NC codes. The real-time NC path generation algorithm can properly deal with issues such as trimming lines, gouging detection, and adaptive tool step adjustment. The developed algorithm has been implemented on a multi-processor CNC system and verified through actual cutting tests. The test results show that no violating conditions occurred on machined part surfaces, and the surface contour error of the cut part is less than the given tolerance, which was 0.02 mm in this particular test.