A clustering based path planning for UV laser galvanometric scanning drilling machine using spatial tessellations with A*

Since the printed circuit board (PCB) of high-density is required, the use of laser drilling machines with galvanometric scanning has recently been increased. The main issue in these machines is to drill many holes at discrete points as fast as possible. For high-speed processes and maximum throughput, the most critical procedure is to find an optimal drilling path to go over all the drilling points. The existing algorithms to find a way of optimized path have only taken the total travel distance of the state into account. However, in case of the laser drilling machines with the galvanometric system, it is possible to process at a higher speed within the certain range formed by scanning lenses because the scanning mirror motion is relatively faster than the speed of the stage. Hence, it becomes a more important problem of laser machines to cluster the processing points of specific ranges as many as possible. This work provides an improved method of optimizing the processing path of laser drilling. We find high density regions in the FPCB by using Delaunay triangulation and make use of A∗ algorithm to find an optimal path for fast processing. The proposed method can be widely applied to many types of processing machines whose operating range is only a part of the stage such as laser machines with galvanometric systems.