Virtual CNC with Performance Error Modeling

Abstract

Speed and accuracy are important criterion for evaluating any NC verification system. The speed must be much faster (preferably by orders of magnitude) than physical machining. The accuracy must meet shop floor usage. Extension of an NC verification system to model the impact of very small CNC performance errors (geometric and thermal machine errors) on the workpiece introduces additional and very stringent demands. Typical performance errors can be as small as 10 microns or less. On a 3 axis CNC, the performance errors can lead to effective 5 axis tool moves (e.g. by rotating the spindle from the nominal tool axis). The central issue is whether any virtual CNC can model such small errors over complex tool paths in reasonable computational times. Progress will be reported on a research program designed to meet these requirements.