A geometry-based investigation of the tool path generation for zigzag pocket machining

Abstract

We present a detailed description of a zigzag algorithm for pocket machining. The algorithm is capable of computing correct zigzag tool paths for multiply-connected planar areas ("pockets") bounded by a wide class of curves. It features a number of optimizations with respect to geometrical and technological objectives. In particular, a near-optimum inclination of the tool path is automatically determined. The underlying geometric principles are simple enough to allow the algorithm to be included in a numerical control computer.

Optimum tool path generation for 2.5D direction-parallel milling with incomplete mesh model

“…Most of the available research has focused on minimizing the number of retractions and reducing the machining time with minimum total lengths. Held [1,6] reported in-depth investigations into reference line selection. However, in most machining companies, the angle of inclination generally is determined according to operators' experience and subjective judgment, because these, despite their inherent limitations, are still regarded as the more optimal approaches.…”

C1Continuous Toolpath Generation Toward 5-axis High Speed Machining

“…NC machining is one of the most common manufacturing scheme available nowadays [1][2][3], [10][11][12], [15], [17][18], [20]. For example, forming die-cavities [2] is one such application.…”

“…The first is based on the intersection of the outline of the pocket with parallel and equally spaced planes. By connecting the parallel adjacent segments that trim the pocket domain into a zig-zag motion, a complete toolpath is constructed [1], [11], [17][18]. This approach is similar to the scan conversion scheme used in computer graphics to render polygonal domains and fill them with pixels [9].…”

New Approximation Methods for Planar Offset and Convolution Curves

“…1, the inner envelope curves do not contribute to the offset and convolution boundaries; their elimination is a direct consequence of the condition: C 1 (t), C 2 (s(t)) > 0. Offset and convolution computations are classic operations in CAD/CAM, which can be used in various interesting geometric applications such as NC machining [8,17], motion planning [3,16,27], character font and brush stroke design [13,14], blending [30], and shape transformation [21].…”