Research On The Motion Control Of Portable Autonomous Underwater Vehicle

In the process of countries in the world entering the oceans,underwater operation equipment plays an extremely important role.As a currently commonly used marine exploration operation device,underwater vehicles play an irreplaceable key role in related marine activities in both civil and military fields.As the specific application of control theory in underwater operation engineering equipment,the control technology of underwater vehicle has great influence and far-reaching significance for the development of underwater vehicles,especially autonomous underwater vehicles(AUV).The research direction of AUV control technology mainly includes the construction of control system architecture,dynamic modeling and reasonable simplification of models and optimization of related parameters,motion control,navigation strategy,path planning,collaborative control,etc.As a key part of the control technology of the AUV,motion control has become an important cornerstone for the AUV to complete the predetermined mission.In this dissertation,a portable autonomous underwater vehicle was taken as the research object.Based on the relevant knowledge of submarine manipulation theory,rigid body kinematics,PID control strategy,sliding mode control strategy and UKF(Unscented Kalman Filter,UKF),the relevant research on the motion control of the portable AUV have been carried out.The research contents include:(1)This dissertation provided a systematic overview of domestic and foreign AUV,and introduced first-class research institutions at home and abroad and typical products with relatively high maturity.At the same time,the motion control technology of AUV and the main control strategies involved in engineering applications are briefly analyzed.(2)Based on the related theories of submarine maneuverability simulation research and the basic theory of rigid body kinematics,a six-degree-of-freedom spatial motion model of the portable AUV was established,and the model was reasonably simplified.At the same time,on the basis of the simplified model,the corresponding motion control model of the portable AUV was further deduced by plane motion decoupling and decomposition.(3)The design process of AUV motion controller and three typical closed-loop control loops applied to AUV motion control were analyzed,and the transfer function of each motion subsystem of the portable AUV were derived.Meanwhile,according to the basic principles of PID control strategy and sliding mode control strategy,the corresponding cascade PID controllers and sliding mode controllers with intelligent integral items are designed.(4)The motion simulation model of the portable AUV was constructed by Matlab software and the Simulink toolbox,and the motion simulation was carried out under typical sailing conditions.Through the simulation results,the control efficiency of the two controllers for the portable AUV motion was tested.At the same time,by comparing and analyzing the simulated motion trajectory,it can be concluded that the sliding mode controller exhibits better response speed and adjustment ability than the PID controller in the portable AUV motion control.(5)The basic principles and implementation steps of the UKF algorithm are outlined,and the drive failure modeling is carried out based on the dynamic model of the portable AUV.At the same time,the specific process of the application of the UKF algorithm in the joint estimation of the state and parameters of the AUV is introduced.Finally,the horizontal plane turning motion of the portable AUV is taken as an example,the effectiveness of UKF algorithm in joint estimation of state and parameters of AUV is verified by numerical simulation.