Redundant Robot Control Algorithm Based on Multi-task Transformation

doi:10.3901/JME.2023.15.083

Abstract

Abstract: Aiming at the problem that the traditional obstacle avoidance algorithm of the redundant robot based on gradient projection cannot achieve obstacle avoidance in task space, a redundant robot control algorithm based on multi-task transformation is proposed. Firstly, based on the obstacle avoidance index H_m in the traditional algorithm, the projection vector index pre-screening method is proposed. The non-collision avoidance links are screened by the projection vector of the obstacle on the robot links. Then distances between possible collision avoidance links and the obstacle are calculated and the shortest distance is obtained by comparing the distances, which reduces the computation of the shortest distance. Secondly, according to the changes of the shortest distance between the obstacle avoidance mark points and the obstacle, the multi-task conversion factors are introduced to realize the smooth transformation of the redundant robot among task space obstacle avoidance, joint space obstacle avoidance, and end-effector trajectory compensation tasks. Finally, a planar 3-DOF redundant robot and a 7-DOF redundant robot are respectively used for comparative simulation analysis and experimental verification. The results show that the robot can effectively avoid obstacles in different positions, and the joint angles and joint angular velocities of the robot can change smoothly and continuously during the movement.

Key words: redundant robot, multi-task conversion, real-time obstacle avoidance, projection vector index pre-screening

CLC Number:

TP242

WU Yi, XU Chao, LIU Liyuan, LIU Jinyue, JIA Xiaohui, LI Tiejun. Redundant Robot Control Algorithm Based on Multi-task Transformation[J]. Journal of Mechanical Engineering, 2023, 59(15): 83-93.

References

[1] HE Z,YUAN F,CHEN D,et al. Dynamic obstacle avoidance planning for manipulators of home[C]//IEEE International Conference on Robotics and Biomimetics (ROBIO),December 06-08,2019,Dali,China,New York:IEEE,2019:2737-2742.
[2] 李亚昕,王国磊,张剑辉,等. 基于碰撞反馈的冗余机器人避障规划算法[J]. 清华大学学报,2022,62(3):408-415. Li Yaxin,WANG Guolei,ZHANG Jianhui,et al. Obstacle avoidance algorithm for redundant robots based on collision feedback[J]. Journal of Tsinghua University,2022,62(3):408-415.
[3] 叶平,孙汉旭,张秋豪. 基于自运动控制的冗余度机器人运动学优化[J]. 机械工程学报,2004,40(12):128-132. YE Ping,SUN Hanxu,ZHANG Qiuhao. Kinematic optimization of redundant robot based on self-motion control[J]. Journal of Mechanical Engineering,2004,40(12):128-132.
[4] MU Z,XU W,LIANG B. Avoidance of multiple moving obstacles during active debris removal using a redundant space manipulator[J]. International Journal of Control Automation and Systems,2017,15(2):815-826.
[5] CAO H R,GU X Q,YU C H. Obstacle avoidance algorithm for redundant manipulators based on weighted generalized inverse[J]. Applied Mechanics and Materials,2017,872:303-309.
[6] 贾庆轩,张倩茹,高欣,等. 预选择最小距离指标的冗余机器人动态避障算法[J]. 机器人,2013,35(1):17-22. JIA Qingxuan,ZHANG Qianru,GAO Xin,et al. Dynamic obstacle avoidance algorithm for redundant robots with pre-selected minimum distance index[J]. Robot,2013,35(1):17-22.
[7] CHEN Y J,JU M Y,HWANG K S. A virtual torque based approach to kinematic control of redundant manipulators[J]. IEEE Transactions on Industrial Electronics,2016,64(2):1728-1736.
[8] WAN J,YAO J,ZHANG L,et al. A weighted gradient projection method for inverse kinematics of redundant manipulators considering multiple performance criteria[J]. Strojniski Vestnik/Journal of Mechanical Engineering, 2018,64(7/8):475-487.
[9] 方承,赵京. 新颖的基于梯度投影法的混合指标动态避障算法[J]. 机械工程学报,2010,46(19):30-37. FANG Cheng,ZHAO Jing. New dynamic obstacle avoidance algorithm with hybrid index based on gradient projection method[J]. Journal of Mechanical Engineering, 2010,46(19):30-37.
[10] LIEGEOIS A. Automatic supervisory control of the configuration and behavior of multibody mechanisms[J]. IEEE Transactions on Systems,Man,and Cybernetics,1977,7(12):868-871.
[11] MACIEJEWSKI A A,KLEIN C A. Obstacle avoidance for kinematically redundant manipulators in dynamically varying environments[J]. International Journal of Robotics Research,1985,4(3):109-117.
[12] ZLAJPAH L,NEMEC B. Kinematic control algorithms for on-line obstacle avoidance for redundant manipulators[C]//IEEE/RSJ International Conference on Intelligent Robots and Systems,30 December 2002-04 Octobor 2002,Lausanne,Switzerland,New York:IEEE,2002:1898-1903.
[13] 申浩宇,吴洪涛,陈柏,等. 基于主从任务转化的冗余度机器人避障算法[J]. 机器人,2014,36(4):425-429. SHEN Haoyu,WU Hongtao,CHEN Bai,et al. Obstacle avoidance algorithm for redundant robots based on transition between the primary and secondary tasks[J]. Robot,2014,36(4):425-429.
[14] 张建华,胡平,张小俊,等. 基于主从任务转化的闭环控制避障算法[J]. 机械工程学报,2017,53(1):21-27. ZHANG Jianhua,HU Ping,ZHANG Xiaojun,et al. Closed loop control algorithm for obstacle avoidance based on the transformation between master and slave tasks[J]. Journal of Mechanical Engineering,2017,53(1):21-27.
[15] 高涵,张明路,张小俊,等. 冗余机器人的任务优先级轨迹规划方法[J]. 机械科学与技术,2018,37(1):27-29. GAO Han,ZHANG Minglu,ZHANG Xiaojun,et al. Task priority trajectory planning method for redundant robots[J]. Mechanical Science and Technology,2018,37(1):27-29.