Robust Coordination Control Of Hypersonic Vehicle Based On Dynamic Coupling Analysis

Hypersonic vehicle,which combines the advantages of " aeronautics" and " astronautics",is one of the important technical fields that the world's military powers are actively investing in.However,due to its severe flight environment,complex non-linear characteristics and serious non-linear coupling of its internal variables,it greatly increases the difficulty of flight control and even threatens flight safety.Therefore,in order to improve the flying quality of hypersonic vehicle,it is a hot and difficult point to study the coupling characteristics of hypersonic vehicle variables and design coordinated control system to cope with the coupling problem.Based on the dynamic coupling analysis of hypersonic vehicle,this paper designs a coordinated controller,and finally solves the coordinated integrated control of the vehicle.The main contents of this paper are as follows:Firstly,based on the published research reports and flight data of hypersonic vehicle at home and abroad,a complete aerodynamic model,dynamic model and propulsion system model of hypersonic vehicle are established.Based on the aerodynamic model of aircraft,a dynamic coupling analysis method is defined.Based on this analysis method,the dynamic coupling characteristics between attitude three-channel and trajectory,dynamic coupling characteristics between three-channel variables,dynamic coupling characteristics between deflection angle of control surface and three-channel variables,and dynamic coupling characteristics between propulsion system and three-channel variables are studied.Combined with the simulation data,the main coupling in the system is analyzed,which lays the foundation for the design of dynamic coordination controller.Secondly,aiming at the attitude mathematical model of hypersonic vehicle,the dynamic coupling matrix between attitude three-channel and deflection angle of control surface is obtained by using the dynamic coupling analysis method proposed above,and the change characteristics of coupling are analyzed.The coordinated controller between three-channel and rudder surface is designed with the idea of hierarchical sliding mode control.The coordinated controller is real-time based on the change of coupling.Changing the control strategy and making use of the strong coupling between channels can effectively solve the influence of coupling on the system.Then,on the basis of realizing coordinated control of three-channel attitude,a more comprehensive dynamic coupling analysis of attitude system is carried out,and the corresponding dynamic coupling matrix is obtained.According to the principle of separation of time scales,the attitude system is divided into fast loop and slow loop.The uncertainties of the two loops are considered separately,and the uncertainties in the two loops are estimated on-line adaptively.In order to ensure the dynamic performance of the system,a new terminal sliding mode control method is adopted and a robust coordination controller of the fast loop and the slow loop is designed.The problems of nonlinearity,strong coupling and uncertainty of attitude system of hypersonic vehicle are solved.Finally,for the longitudinal mathematical model of hypersonic vehicle,the dynamic coupling matrix of attitude,trajectory and deflection angle of control surface and throttle setting in the longitudinal system is obtained by using the dynamic coupling analysis method proposed above,and the changing characteristics of coupling are analyzed.According to the variations of variables in the trajectory system and attitude system,the coordinated control methods of the common sliding mode and the new terminal sliding mode combined with the coordinated control term are used to design the coordinated controller of the longitudinal system.The attitude and trajectory of the aircraft are controlled efficiently by the control surface and propulsion system.On the basis of realizing coordinated control of longitudinal system,the uncertainties of parameters and complex disturbances of longitudinal system are considered,and the uncertainties in the system are estimated on-line adaptively.The Robust Coordinated Controller of the longitudinal system is designed,and the effectiveness of the control is verified by simulation.