The control of machining errors of tool path for unequal diameter flank milling of globoidal cam

Abstract

The profile error is inevitable in the machining process of globoid cam. In order to tackle the problem of normal vector anisotropy in unequal diameter machining, the offset point optimization algorithm is served to optimize the tool position according to the error transfer relationship of equidistant surfaces and the characteristics of unequal diameter tool path generation. In this paper, a bidirectional search algorithm is devised to minimize the deviation between unequal diameter machining tool path surface and fitting ruled surface. The optimal numerical solution with high accuracy is obtained by genetic algorithm. And then the end points of the tool axis are regarded as the initial data. Inverse interpolation of the NURBS (Non-Uniform Rational B-Spline) interpolation is utilized to reconstruct the ruled surface of the flank milling tool path. The simulation results verify the effectiveness of the proposed approach. Compared with the existing methods, the presented one reduces the machining error greatly.