关键词: 机械臂, 路径规划, 改进RRT*-connect, 梯度下降法

Abstract:

Based on the bi-directional asymptotically optimal RRT*-connect algorithm, the motion planning of the high-dimensional manipulator is analyzed, so as to make the search path in the planning process shorter and more efficient. Firstly, the target bias strategy is introduced into the sampling process, and the sampling area is constrained to ensure that each sample can be searched towards the target direction, therefore the optimal searching path can be obtained. Secondly, based on the above operation, the gradient descent method is adopted to optimize the searched path, smoothing the whole path and removing the large angle turn. Then, the improved RRT*-connect algorithm is simulated and analyzed by Matlab. It is demonstrated that the algorithm can guarantee the probabilistic completeness and asymptotic optimality of searching under various complex environment, and the shorter searching path is obtained in shorter time. Finally, a simulation experiment is conducted on the ROS platform with UR5 manipulator to verify the practicability and effectiveness of the algorithm.

Key words: manipulator, path planning, improved RRT*-connect, gradient descent method