A general mathematical model for optimizing NC tool path for face milling of flat convex polygonal surfaces

Abstract

SUMMARY Milling is one of the most widely used metal removal processes. The number of decision parameters involved in the milling operation makes the experimental estimation of tool life equations very dimcult. Optimal metal removal rate has been modelled independently of the cutter path selected for the operation. However, the choosing of the proper cutter path might significantly reduce the total tool travel and therefore also reduce the tool wear due to the reduction in the tool engagement with the job With the widespread application of robotics in industry, robots are also being used to automate the grinding process. Robotized grinding of flat polygonal surfaces is one such application where the tool path is similar to face milling of like surfaces. Thus optimizing the total tool path during NC face milling/robotized grinding remains an important problem A mathematical model representing the total tool path on an N-sided convex polygonal surface has been developed. The stair-case type of tool path has been considered. The resulting formulation is complex and cannot be solved using standard analytic or numeric methods. An algorithm has been proposed to find an optimal solution using the above model, by enumerating over tool sweep angles between 0° and 180°. This algorithm can be easily coded and run on a PC. Finally a detailed example is given explaining the application of this algorithm.