POCKET MACHINING BASED ON CONTOUR-PARALLEL TOOL PATHS GENERATED BY MEANS OF PROXIMITY MAPS

A fundamental NC-machining problem is the clearing of areas within specified boundaries from material. The paper presents an efficient algorithm for generating largely optimal tool paths to solve this pocket-machining problem for multiply connected planar pocket areas bounded by curvilinear boundaries. Using certain concepts of computational geometry, i.e. Voronoi diagrams and monotonic pouches, offsets of a pocket boundary are efficiently generated. Further, it is explained how the tool path can be optimized with respect to several criteria arising from technological requirements. The concepts presented have been implemented, and they form the basis of the pocketing package LARK.