A*-PRM: A Dynamic Weight-Based Probabilistic Roadmap Algorithm

Robot path planning is a fundamental challenge in enhancing the environmental adaptability of autonomous navigation systems. This paper presents a hybrid path planning algorithm, A-star PRM, which incorporates dynamic weights. By embedding the Manhattan distance heuristic of the A-star algorithm into the random sampling process of PRM, the algorithm achieves a balanced optimization of path quality and computational efficiency. The approach uses a hierarchical sampling strategy and a dynamic connection mechanism, greatly improving adaptability to complex obstacle distributions. Experiments show that under a baseline configuration with one thousand sampled vertices, the path length of A-star PRM is 1073.23 plus or minus 14.8 meters and is 42.3 percent shorter than that of PRM with p value less than 0.01. With high-density sampling using three thousand vertices, the path length is reduced by 0.94 percent, 1036.61 meters compared with 1046.42 meters, while the increase in computational time is cut to about one tenth of the PRM increase, 71 percent compared with 785 percent. These results confirm the comprehensive advantages of A-star PRM in path quality, stability, and computational efficiency. Compared with existing hybrid algorithms, the proposed method shows clear benefits, especially in narrow channels and scenarios with dynamic obstacles.