Tool-path transition technology of CPO corner for complex pocket

Aiming at the corner and residual problem in Contour-Parallel Offset (CPO) tool path, a three clothiod curves blending method was used to make transition optimization. The skeleton extraction method was taken to compute the corner residual region. Based on residual region, the controlled points and initial connected points were selected as feature points. The clothoid and lines were connected on the constraint of feature points, which were able to keep the transition up to C2 continuous. The experimental results showed that this method could not only clean the residual region and achieve a smooth transition machining effectively, but also minimize the machining time and improve the machining quality.