B-spline tool offset of a free-form curve in the shoe last high-speed machining CNC system

Aiming at the special requirements of a shoe last high-speed machining process and the large dataset which could be gained by the reverse engineering technique, this paper analyzes the conventional tool-offset methods and presents a B-spline tool-offset model. A simple vector-analyzed algorithm to smooth the tool-offset curve in which there are local strange points is proposed, and then the second tool-offsetting, which obtains the fine data of the machining tool’s center points, is directly processed. To reduce the error from tool offsetting of the C2 continuity curve, this paper gains a smoother curve after processing via the edge points joint algorithm, which effectively solved the overcut or undercut problems in the high-speed machining of the spline curve.