Maneuvering Performance Investigation And Motion Simulation Of The Streamlined UVMS

The ocean area accounts for two-thirds of the total area of the earth,and contains a large amount of rare earth resources,oil and gas resources,and mineral resources.With the increasing human exploration and development activities in the ocean,various underwater vehicles are widely used in marine engineering.The autonomous underwater vehicle has a unique working ability,which has become an important development direction of the current working underwater vehicles.In this paper,the maneuverability analysis and motion simulation of streamlined underwater operation vehicle are carried out for the hydrodynamic problems faced by the underwater manipulators.First of all,combined with the captive model tests and simulations,this paper studies the relationship between hydrodynamic forces and the joint angular velocity and angular acceleration when the manipulator is mounted on the streamlined AUV.This paper investigates the influence of the Circulating Water Channel(CWC)sides wall and support struts on the hydrodynamic coefficient prediction for autonomous underwater vehicles(AUVs).Computational Fluid Dynamics(CFD)method has been used to model the CWC tests.The hydrodynamic coefficients estimated by CFD are compared with the prediction of experiments to verify the accuracy of the simulations In order to study the effect of the sides wall on the hydrodynamic characteristics of the AUV in full scale captive model tests,this paper uses the CWC non-dimensional width parameters to quantify the correlation between the CWC width and the hydrodynamic coefficients of the chosen model.The result shows that the hydrodynamic coefficients tend to be constant with the CWC width parameters increasing.In addition,the side wall has a greater influence on the experiment results than the struts.This study provides recommendations for reducing the effects of sidewalls and struts on experiment results.Secondly,the effects of the disturbance of the underwater manipulator are investigated by experiments and simulations.The results show that the hydrodynamic forces of the manipulator are closely related to the velocity and acceleration of its relative fluid.In order to limit the influence of the disturbance of the manipulator,a simple method is to reduce the movement speed and acceleration of the joints of the manipulator carried by the hovering vehicle as much as possible,and to keep the manipulator with a small speed and acceleration relative to the fluid.Although this will reduce the efficiency of the work,it can achieve better control results.Finally,this paper solves the acceleration coefficient,velocity coefficient,angular velocity coefficient and coupling coefficient through the Hess-Smith method of the potential flow theory and the circulating water channel resistance model test.The modeling of the underwater vehicle was completed,and the inertia matrix,centrifugal force and Coriolis matrix,gravity matrix in the dynamic equation were obtained.The modeling of the manipulator uses the Lagrange dynamics modeling method.The dynamic model of the 4-DOF manipulator is calculated by the symbolic variable calculation method.The hydrodynamics of the manipulator are modeled using empirical formulas.Based on the virtual guidance method,the three-dimensional trajectory tracking simulation of the streamlined underwater vehicles is carried out on the MATLAB platform.The results show that the AUV can accurately track known trajectories.