The Study Of UVMS's Coordinated Control Method Based On Task

With the massive exploitation and use of land resources by mankind,the limited land resources are depleted day by day,and all countries are turning their attention on the development of the vast oceans rich in resources and mineral resources.The design of the Underwater Vehicle-Manipulator System(UVMS)and its related technologies,which play an important role in the development of marine resources and have become the hot spots for scholars and research institutions in various countries.The subsystems AUV system and manipulator system of UVMS have a strong coupling,strong nonlinearity and redundancy.And the research of the coordinated control technology of UVMS has become a key issue to be solved urgently.This paper research the cooperative control of UVMS based on task from the aspects of joint space tracking technology and kinematics planning technology respectively.Firstly,this paper designs the overall scheme of UVMS system,including three parts of the Autonomous Underwater Vehicle(AUV),underwater manipulator and auxiliary adjustment device.According to the design requirements,the overall framework of the system is built.Under the AUV operating requirements,the performance parameters of underwater manipulator are explained,and the system composition of underwater manipulator is determined.Besides,a sliding module-based auxiliary adjustment device is specialized designed,which can be used to compensate the interference of manipulator to AUV.Secondly,the underwater vehicle system,underwater manipulator system,overall UVMS kinematics and dynamics model are established respectively.By analyzing the movement of the body and the underwater manipulator in the water and the corresponding motion coordinate system are established.Further,the rotation matrix and Jacobian matrix are got,and then the kinematic equations can be established;The dynamic equations of the two subsystems are developed based on the analysis of the hydrodynamic force;On this basis,the overall UVMS dynamic model is derived through the Newton-Euler iterative method.Thirdly,by analyzing manipulator system,a RBF neural network adaptive control algorithm based on model approximation is designed to approach the indeterminate interference under water.And simulation studies were presented that illustrated the effectiveness of this method.The problem of disturbing torque produced by the manipulator on the body in the pitch direction is serious,the auxiliary adjustment device designed in this paper compensates for disturbing moments in the pitch direction by adjusting the center of gravity.And a fuzzy PID control method is used to do the coordinate control.Besides,a double closed-loop integral sliding mode controller are designed for the strongly nonlinear system of UVMS and analysis and comparison of this method through simulation,it ensures the stability of the body and provide a strong guarantee for completing the job task smoothly.At last,to solve the problem of UVMS motion redundancy,a multi-task priority motion planning method based on fuzzy logic is adopt.This method can make the position of the end effector reach the desired position,while ensuring the attitude stability and avoiding the joint limit.By simulations,the effectiveness of this method is verified.