TSP-based depth-first search algorithms for enhanced path planning in laser-based directed energy

Abstract

In the field of laser-directed energy deposition, it is crucial to optimize the path planning to improve the mechanical properties and ensemble fidelity of the precision printed samples. The traditional path planning methods typically require layer-by-layer calculation of the intersections between the scan lines and the contour loops, which leads to substantial redundant computations and low forming precision. In order to solve these problems, this paper transforms the path optimization into the Travelling Salesman Problem (TSP), followed by realizing the strategy of continuous inter-layer scanning through depth-first search. This method can generate efficient, non-intersecting connection paths in a short time, effectively reducing the total length of the connection path and processing time. Experimental results show that compared with the conventional zig-zag strategy, the path planning method based on TSP performs well in terms of near-net shape, compactness, and hardness of the molding samples. By shifting the intersection areas of the path to the outer contour and interacting the long and short sides, the method can realize the high precision joint part without gap forming and reduce the internal defects of the component.