摘要
相对于传统机械臂,9自由度超冗余机械臂有更强的避障能力、更大的应用价值。目前国内对串联机械臂的避障研究主要集中在7自由度机械臂上,而对超冗余机械臂(自由度大于或等于9)还未做深入研究。为此,基于bi_RRT(双树快速扩展随机树)算法提出了一种改进算法,即在创建搜索树之前先保存一条完整的无障碍路径,再对9自由度臂进行避障研究。首先建立了正逆运动学模型和障碍物模型;然后提出了一种改进的bi_RRT算法对机械臂进行避障路径规划;最后在二维与三维环境中对算法进行避障仿真测试。二维平面路径规划仿真中,改进算法平均路径搜索时间从0. 25s减小到0. 05s;9臂壁障仿真中,改进算法平均路径搜索时间从一小时减小到十分钟。仿真结果表明:改进算法所生成的路径,可以很好地实现9自由度臂的避障过程,且具有较大的应用空间。
Compared with the conventional manipulator, the 9-d of freedom of super-redundant manipulator has stronger obstacle avoidance ability and greater application value. At present, the research on the obstacle avoidance of the series manipulator mainly focuses on the 7 degree of freedom manipulator. However, the manipulator with higher degree of freedom (degrees of freedom is greater than or equal to 9) has not yet been studied. Therefore, an improved algorithm based on bi_RRT algorithm was proposed in this paper to save initial tree. Save a complete barrier free path before creating search tree at first. Then do obstacle avoidance on the 9 degree of freedom arm. Firstly, the inverse kinematics model and obstacle model were established;Then an improved bi_RRT algorithm was proposed for obstacle avoidance path planning of robot arm. Finally, obstacle avoidance simulation test was carried out in 2D and 3D environments. In the 2D planar path planning simulation, the average search time of the improved algorithm was reduced from 0. 25s to 0. 05s. The 9-arm simulation results show that the average search time of the improved algorithm decreases from one hour to ten minutes. The test results show that the algorithm can satisfy the search path of the 9 arm obstacle avoidance. The above results have a certain application value.
作者
由弘扬
贺帅
刘宏伟
徐振邦
YOU Hong-yang;HE Shuai;LIU Hong-wei;XU Zhen-bang(Changchun Institute of Optics,Fine Mechanics andPhysics,Chinese Academy of Science,Changchun Jilin 130033 ,China;University of Chinese Academy of Sciences,Beijing 100049,China)
出处
《计算机仿真》
北大核心
2019年第7期308-313,共6页
Computer Simulation
关键词
九自由度
机械臂
超冗余
快速扩展随机树
路径规划
9 degrees of freedom
Manipulator
Hyper redundancy
Fast spread random tree
Path planning
