Research On Coordinated Motion Planning Of Dual Manipulator

With the rapid development of society and the increasing maturity of science and technology,robots have been applied in various fields of production and life widely.People urgently expect robots to have more human-like functions to meet the increasing requirements of human in industry,medicine and services.Compared with single arm robot,dual arm robot has more extensive application prospects in assembly and transportation,equipment maintenance,personnel rescue,exploration and detection,surgery and medical treatment,and even family care.In this article,the forward and inverse kinematics model of WLR-III dual-arm robot is established,the experimental platform of the dual-arm robot is built based on the software environment ROS/Move It! and WLR-III,and the coordinated motion planning method of the dual-arm robot is mainly studied and the experimental verification is completed on the dual arm system of WLR-III.Firstly,the structural characteristics of WLR-III are analyzed.The parametric representation of the dual arm robot is completed by using D-H method,and the D-H parameters of the dual arm are determined.Combined with reverse method the closed form forward and inverse kinematics of the dual arm robot is derived,an optimization method of inverse kinematics solution is proposed,and its singularity is analyzed.The instantaneous kinematics of the dual arm robot is derived,the basic Jacobian matrix is solved.The workspace of the robot is obtained and analyzed,which lays the foundation for the subsequent motion planning of the dual arm robot.Secondly,based on bounding box collision detection method,combined with the structural characteristics of WLR-III robot,a collision detection strategy of dual arm robot based on hybrid bounding box of sphere,cylinder and capsule is proposed.A simplified model of dual arm robot for collision detection is established,and various situations of possible collision of dual arm robot in the process of motion are analyzed.The collision detection problem is transformed into solving the minimum distance between bounding boxes,and collision warning can be realized.The secondary projection method is used to improve the efficiency of collision detection.Thirdly,the motion planning algorithm of dual arm robot based on RRT algorithm is studied,The algorithm uses random sampling method for motion planning,and studies the characteristics and performance of improved RRT connect and RRT* algorithms.For WLR-III robot,a specific trajectory planning method and trajectory interpolation algorithm are proposed.The motion planning simulation and experiment are carried out in the application scenario of grasping tool on the table and putting it back with a manipulator.Finally,the coordinated motion planning method of dual arm robot is studied.According to the motion constraints between the two arms,the coordinated motion of the two arms is divided into independent motion,loose coordinated motion and tight coordinated motion.The master-slave planning method is used to analyze and deduce the pose and velocity constraints of the above three kinds of coordinated motions,and the simulation and experiment of dual arm coordinated motion are carried out in the application scenario of moving objects with dual manipulator.