Trajectory Tracking And Formation Control Of AUV Based On Filtered Backstepping Method

Autonomous underwater vehicles are an important tool for underwater energy exploration.At the same time,they are attracting attention in pollution source search,military and commercial.As the number of underwater applications continues to increase,the demand for autonomous underwater vehicles is growing.This thesis mainly studies the trajectory tracking and formation control of autonomous underwater vehicles.It is assumed that the dynamic model parameters of the autonomous underwater vehicle are partially unknown.The radial basis function neural network is used for approximation.The design method of the control law mainly adopts the backstepping method.Aiming at the plane motion and the three dimensional motion of autonomous underwater vehicles,the main research contents are as follows:1.Based on the dynamic surface method,the autonomous underwater vehicle plane trajectory tracking and formation controllers are designed to make the autonomous underwater vehicle complete the plane trajectory tracking and formation movement.In the first part,the autonomous underwater vehicle plane trajectory tracking control law is designed based on the dynamic surface method,so that the autonomous underwater vehicle can track and maintain the desired trajectory,and the tracking error converges to a compact set.In the second part,based on the situation of leaderless,the formation control law of autonomous underwater vehicle is designed based on the dynamic surface method,so that the autonomous underwater vehicle maintains the desired distance and achieves the purpose of formation control.In the third part,based on the leader-follower situation,the autonomous underwater vehicle formation tracking control law is designed based on the dynamic surface method,so that the autonomous underwater vehicle can form a formation and track the virtual leader's state in a fixed formation.2.The three-dimensional space trajectory tracking and formation controller of the autonomous underwater vehicle is designed based on the finite time command filter method,so that the autonomous underwater vehicle completes the three dimensional space trajectory tracking and formation movement.Considering the error caused by filtering will affect the performance of the system to some extent.In order to improve the tracking accuracy of the system,a filter tracking error compensation loop is designed to optimize the tracking accuracy.The first part designs the three-dimensional space trajectory tracking control law of the autonomous underwater vehicle,so that the autonomous underwater vehicle can track and maintain the desired trajectory.The second part designs the three-dimensional space formation tracking control law of the autonomous underwater vehicle,which makes the autonomous underwater vehicle form a formation structure and can track and maintain the state of the virtual leader in a fixed formation.Finally,the Lyapunov function is used to prove the stability of the autonomous underwater vehicle system under the action of the above designed control law.The trajectory tracking and formation control laws designed by the above are simulated by Matlab software.The simulation results verify the feasibility of the designed control law.