Research On Nolinear Control Method Of Underwater High-speed Navigation

With the continuous upgrading of the requirements of modern underwater vehicles,supercavitation technology has become the mainstream technology of underwater highspeed navigation bodies due to its significant drag reduction effect.Therefore,it is urgent to study the control technology of supercavity vehicles.The thesis takes underwater highspeed navigation as the research object,and researches its control method.Firstly,it uses dynamic inverse optimal control method to design the controller of its cruise cruise section,and in the acceleration section,it is converted into LPV system,and Based on this LPV system,a robust variable gain controller design is developed.First,systematically investigate the technical development and research status of supercavity navigation bodies at home and abroad,analyze and discuss the theory of the establishment of the cavity model,and comb the control methods of the high-speed underwater navigation body and the robust variable gain control method.The current research situation gives the main content of the paper.Secondly,the mathematical model of the underwater high-speed navigation body was established.On the basis of the principle of Logvinovich independent expansion,the semi-theoretical and semi-empirical formulas of the bubble morphology model were derived,and the theory of tail gliding force and moment was derived based on the bubble morphology model.Formula,considering the force of the head of the cavitation,gravity and other forces,the kinematics and dynamics numerical model of the navigation body is established.Then,in order to facilitate the study of control theory,the navigation body model is simplified into a longitudinal model,and only its longitudinal plane is considered,and its dynamic performance is analyzed.The optimal control method is designed for the controller,and the simulation results show that the controller can be effectively controlled during the cruise control of the system.Finally,in order to control the acceleration section of the navigation body,the navigation body system is converted into a multicellular LPV system form,the theoretical basis of the robust variable gain control method is explained,and various interferences encountered by the navigation body during the movement process are analyzed.In addition,a robust variable gain controller is designed,and simulation shows that this control method can perform stable control on the acceleration section of the navigation body,and has good robustness.