关键词: 加工, 平滑压缩, 圆弧, 二次有理Bézier, 样条插补

Abstract: To implement high-speed and high-precision machining of arcs in the micro-line form,the arc smooth compression interpolation algorithm was proposed.Based on double-chord error limit,the machining path could be divided into two region types.For those regions comprised of discontinuous small-line segments,the linear interpolation was performed between the adjacent command points.For those continuous regions,the shape-defining point was selected by curvature extremum and bend direction of the machining path;these points were fitted into quadratic rational Bézier curves to compress segments and smooth contours;the arc was recognized with curve feature then transformed to geometric form and merged with adjacent one;the arc interpolation was performed on the curve of geometric form.The results of experiments revealed that the proposed algorithm could reduce velocity fluctuation and implement high-quality CNC processing of the arc.

Key words: machining, smooth compression, circular arc, quadratic rational Bézier, spline interpolation