Task-Point Sequencing and Trajectory Generation/Optimization with Benchmarking for Multi-axis Percussion Laser Drilling of Jet Engine Combustion Chamber Panels

Abstract

Percussion drilling is a type of laser drilling operation for which optimized 5-axis trajectory planning has been developed. While percussion drilling is less advantageous in terms of local thermal loading and achievable part quality, it is used extensively in industry, due to its simplicity of automation compared to on-the-fly drilling. Thus, a TSP-style trajectory planning algorithm has been developed for percussion laser drilling. The novelty, in this case, is concurrent planning of 5-axis time-optimal point-to-point movements within the sequencing algorithm, and direct minimization of the total travel time, rather than just distance (in two Cartesian axes), as is the method for which a significant portion of TSP solvers and trajectory planners in the literature has been developed. Compared to currently applied methods, 32–36% reduction in the beam positioning time has been achieved. Also, 39–45% reduction in the peak magnitude of vibration has been realized. Limited benchmarking with the state-of-the-art TSP solvers from combinatorial mathematics, considering only 2-axis Euclidean distance as the objective function, indicates that the proposed sequencing algorithm for percussion drilling is sub-optimal by 9–12%. Thus, it can still use further improvement in future research. Nevertheless, the trajectory planners that have been developed in this paper for percussion drilling have experimentally demonstrated very promising improvements in terms of motion time and smoothness. As more advanced laser control electronics with deterministic execution and rapid synchronization capability become available, such algorithms are expected to facilitate significant production gains in laser drilling processes used in different industries.