Optimizing the numerical algorithm in Fast Constant Engagement Offsetting Method for generating 2.5D milling tool paths

摘要

In the case of 2.5D rough milling operations, machining efficiency can significantly be increased by providing a uniform tool load. This is underpinned by the fact that uniform load has a positive effect on both tool life and machining time. Unfortunately, conventional contour-parallel tool paths are unable to guarantee uniform tool loads. However, nowadays there are some advanced path generation methods which can offer a constant tool load by controlling the cutter engagement angle. Yet, the spread of these non-equidistant offsetting methods is hindered by their dependence on complex calculations. As a solution to this problem, the Fast Constant Engagement Offsetting Method (FACEOM), developed in the scope of our previous study, is seen to be taking a step towards reducing computational needs. In this paper, suggestions for further improvements of FACEOM are presented. Decreasing the number of path points to be calculated is made possible by implementing adaptive step size and spline interpolation. Through simulation tests, it was also analysed which of the numerical methods utilized for solving boundary value problems can be applied to obtain the shortest calculation time during tool path generation. The practical applicability of the algorithm has been proved by cutting experiments. With respect to research results, this paper also describes how a tool path created by the algorithm can be adapted to controllers of CNC machine tools. Solutions presented in this paper can promote a wider application of a modern path generation method that ensures constant tool loads.