Abstract: In the operation process of orchard spray robot, path planning, as the core problem of orchard spray robot, has the problems of low smoothness of planned path, low efficiency of algorithm search and close to obstacles. Aiming at the problem of orchard spray robot avoiding dynamic obstacles in real time and planning a better global operation path in complex orchard environment, a path planning algorithm for orchard spray robot based on improved A* algorithm and dynamic window approach（ DWA ） is proposed. Firstly, the heuristic function of A* algorithm is optimized, so that the algorithm can plan a path in the center line of fruit trees. Then, by adding multiple guiding points to the grid map, the A* algorithm is guided to complete the preliminary global path planning of the orchard. Finally, combined with DWA algorithm to track the initial global path and avoid dynamic obstacles in real time, the global path planning of orchard spray robot is completed. MATLAB is used for simulation verification. The experimental results show that the improved algorithm plans the center line path between orchard rows while avoiding obstacles. The path is smooth and better, which can meet the operation requirements of orchard spray robot in complex environment.

Key words: path planning, A* algorithm, dynamic window approach（DWA）, orchard spraying robot, path optimization

摘要： 在果园喷雾机器人的运行过程中，路径规划作为果园喷雾机器人的核心问题，存在着规划出的路径平滑度低、算法搜索效率低以及靠近障碍物等问题。针对果园喷雾机器人在复杂果园环境中实时躲避动态障碍物并规划出较优的全局作业路径问题，提出了一种改进A*算法和动态窗口法（dynamic window approach，DWA）的果园喷雾机器人路径规划算法。优化A*算法的启发函数，使该算法能够规划出一条位于果树行间中心线的路径；通过对栅格地图中加入多个引导点，引导A*算法完成果园的初步全局路径规划；结合DWA算法对初步全局路径进行追踪并实时躲避动态障碍物，完成果园喷雾机器人的全局路径规划。使用MATLAB进行仿真验证，实验结果表明，改进后的算法在躲避障碍物的同时规划出现果园行间中心线路径，路径平滑较优，能够满足果园喷雾机器人在复杂环境中作业需求。

关键词: 路径规划, A*算法, DWA算法, 果园喷雾机器人, 路径优化