关键词: 移动机器人, 路径规划, A*算法, 双向搜索, 机器人操作系统

Abstract: A* algorithm is widely used in path planning of mobile robots. However, there are many problems of the traditional A* algorithm such as long search time and low efficiency. Therefore, two-way search algorithm is presented to improve the traditional A* algorithm. The algorithm can search both positive and negative paths during the process of path planning simultaneously. The alternating mechanism of forward and backward searches can be used, and it has a good performance. The final target node is searched and meets in the midpoint area of the connection, and the calculation time of path finding can be reduced. Simulation experiments of the improved A* algorithm can be carried out on the MATLAB platform, and the result shows that the two-way A* algorithm can reduce planning time and generate the optimal path. This algorithm can be applied on Turtlebot 2 mobile platform based on open source robotic operating system. Field experiments show that the bidirectional A* algorithm can reduce the calculation time of path finding. Thus the efficiency of path searching can be improved, and the planning path is reasonable for the requirements of path planning significantly.

Key words: mobile robot, path planning, A* algorithm, bidirectional search, robot operating system