Application of the Traveling Salesman Problem in Generating an Optimized Collision-Free Tool Path for CNC Drilling

In drilling, the tool path is usually generated according to the workpiece geometry and the arrangement of holes. To perform drilling, majority of Computer-Aided Manufacturing (CAM) software offer a set of predefined drilling strategies. In this context, tool traveling time between the holes is considered as a non-value-adding movement and thus must be minimized. However, generating the optimum tool path with the shortest possible traveling distance in the presence of obstacles received little attention and therefore, CAM-generated tool paths are not necessarily optimum. This paper introduces a new algorithm based upon Traveling Salesman Problem (TSP) to minimize the tool path length while considering collision avoidance. The developed optimization model considers multiple constraints, including the location of tool origin and the presence of obstacles along the tool path, to generate a collision-free trajectory with minimum length. Performance of the proposed model was compared to the tool path generated by HSMWorks CAM software and the results confirmed the ability of the algorithm in generating an optimum or near-optimum, collision-free tool path for real-world drilling applications with a minimal computational time.