Machining Triangular Mesh Surfaces via Mesh Offset Based Tool Paths

AbstractThis paper presents a new method to generate iso-planar numerical control (NC) tool paths for the finishing machining of triangular mesh surfaces. One main concern in generating the piecewise linear NC tool paths is to ensure that their resulting machining errors are within the specified tolerance. To this end, it is proposed that the cutter location (CL) tool paths be within the 3D tolerance zone defined by two offset surfaces of the triangular mesh surface. One offset surface corresponds to the under-cut limit and the other offset surface corresponds to the over-cut limit. Also, the scallop-height offset surface is used to facilitate the determination of side steps between adjacent iso-planar tool paths. The common self-intersections in the offset triangles are eliminated using the Z-map approach. The applicability and effectiveness of the presented method was validated through implementations on typical triangular mesh surfaces.

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