not-yet-known not-yet-known not-yet-known unknown in this paper an improved A* algorithm which combines a priority-based node selecting strategy and a novel termination condition for bidirectional search was proposed. Through numerical experiments on grid maps of various sizes and complexity, it is found that this improved A* algorithm searches much less nodes and thus take substantially less time in pathfinding compared to the traditional bidirectional A* algorithm. The superiority of the improved A* algorithm become more pronounced as map size grows.