Research On ROV Dual-arm Motion Planning Method Based On Job Task

With the development of exploring deep sea and researching oceans resources,the deep-water dual-arm applied to operational ROV plays an important role.In order to improve automation level and operation efficiency of underwater manipulator,based on the ROV dual-arm as an example,we do some research on the underwater manipulator motion model,water dynamics,path planning,arms arm motion coordination.Firstly,the research background,purpose and significance of the research for underwater manipulator and dual-manipulators coordinate-operation are described in this part,especially the related research in china and abroad are presented.Then,the key problems for the dual-manipulators coordinated work in the deep-sea are illustrated.Secondly,taking the underwater manipulator equipped with ROV as an example,the section analyzes kinematics of underwater manipulator,and kinematics model is established in this section.The kinematic model of seven function and five function underwater manipulator is established by D-H method,and calculating inverse kinematics result of underwater manipulator.According to the Lagrange method,underwater manipulator dynamics model is established.Aiming at the flow environment,the hydrodynamic model of the underwater manipulator under the interference of water flow environment is established,and the torque of each arm of the manipulator is calculated by Morison formula.Thirdly,Rapidly-exploring Random Tree Star(RRT*)obstacle avoidance path planning algorithm is proposed.Firstly,in order to solve the problem of obstacle avoidance in manipulator operation,a collision detection algorithm based on particle model is proposed.Then the RRT algorithm is introduced as the manipulator path planning method,and the RRT algorithm is introduced,including its basic ideas and algorithm flow.Through the analysis of the advantages and disadvantages of RRT algorithm,RRT* algorithm is introduced,and the basic RRT algorithm and RRT* algorithm are compared through simulation experiments,the results show that RRT* algorithm converges faster,can approach the optimal path.Fourthly,the kinematics relationship of the double manipulator system is analyzed deeply,and three typical tasks are analyzed and simulated,which are the independent movement of arms,coordinated handling and coordinated socket,the simulation results show that based on the kinematic relationship of double manipulator system,the discrete points on the manipulator path can reach,and the manipulator runs smoothly during the operation,which proves the correctness of kinematics analysis of the double manipulator.Finally,the experimental platform of double manipulator system is established,and the single manipulator obstacle avoidance path planning experiment and the dual-manipulators motion coordination experiment are carried out respectively.According to the three types of double arm system movement,double arm motion coordination experiments are carried out respectively the dual-manipulators independently movement test,coordinated transport task,coordinated socket task.The experimental results verify the correctness of the kinematics analysis of the single manipulator path planning and the double-manipulator motion coordination,which lays the foundation for the realization of the double-arm system.