Efficient tool path computing in CAD/CAM: distributed computation for trajectory generation

Abstract

Tool path generation is one of the most complex problems in Computer Aided Manufacturing. Although some efficient strategies have been developed to solve it, most of them are only useful for 3 and 5 axis standard machining. The algorithm called Virtual Digitising computes the tool path by means of a “virtually digitized” model of the surface and a geometry specification of the tool and its motion, so can be used even in non-standard machining (retrofitting). This algorithm is simple, robust and avoids the problem of tool-surface collision by its own definition. However, its computing cost is high. Presented in the paper there is a Virtual Digitizing optimisation that takes the advantages of distributed computing (using different computer architectures) in order to improve the algorithm speed. A comparative study will show the gain and precision achieved. The proposed algorithm has been successfully implemented in a commercial CAD/CAM system specialized in shoe last making. Finally, some illustrative examples are shown.