基于改进RRT的采摘机械臂避障运动规划研究

On Obstacle Avoidance Motion Planning of Picking Manipu⁃lator Arm based on Improved RRT

针对传统RRT算法用于采摘机械臂避障路径规划上存在的搜索方向具有盲目性、搜索节点较多等问题,提出一种改进的RRT算法设计。首先,以Aubo-i5机械臂为实验主体,进行机械臂运动学分析,构建D-H参数表、机械臂三维模型,并采用包络法对机械臂进行碰撞检测;其次,对传统RRT算法进行优化策略改进,引入APF算法和广度优先搜索方法优化剪枝节点,进行算法流程分析;最后,使用RRT算法、RRT*算法、RRT-Connect算法和本文改进算法在不同场景的地图环境中进行运动规划,将改进算法用于机械臂避障抓取仿真实验。通过仿真实验结果表明,改进后的算法中节点搜索方向更准确、搜索节点变少、收敛速度更快,算法的效率的都得到大幅度的提升,验证了该算法的有效性和可靠性。

Aiming at the problems of blindness in the search direction and many search nodes in the ob-stacle avoidance path planning of the traditional RRT algorithm for picking manipulators,an improved RRT algorithm design is proposed.Firstly,taking the Aubo-i5 manipulator as the experimental sub-ject,the kinematics of the manipulator were analyzed,the D-H parameter table and the three-dimen-sional model of the manipulator were constructed,and the collision detection of the manipulator was carried out by the envelope method.Secondly,the optimization strategy of the traditional RRT algo-rithm is improved,and the APF algorithm and breadth-first search method are introduced to optimize the pruning nodes,and the algorithm process analysis is carried out.Finally,RRT algorithm,RRT*al-gorithm,RRT-Connect algorithm and the improved algorithm in this paper are used to carry out mo-tion planning in the map environment of different scenarios,and the improved algorithm is used for the obstacle avoidance and grabbing simulation experiment of the robotic arm.Through simulation experi-ments,the results show that the node search direction is more accurate,the search node is less,the convergence speed is faster,and the efficiency of the algorithm is greatly improved,which verifies the effectiveness and reliability of the algorithm.