Coordinated Integrated Control Of Hypersonic Flight Vehicle Based On Coupling Analysis Method

Hypersonic flight vehicles(HFVs)are superexcellent weapons in aerospace battlefield in the future.It is of great strategic significance for China's aerospace environment security and the international aerospace military force balance to research and master the related technologies of HFVs.However,HFVs have characteristics such as strong nonlinear,strong coupling,fast time-varying,and uncertainty,which make the flight control become an important and difficult problem in the process of its development.In order to eliminate the negative impact of the strong coupling and to improve the flight quality,the coordinated integrated control of HFVs is studied in this paper.The main research contents are listed as follows:Firstly,according to the public experimental data and former achievements,the nonlinear dynamics and aerodynamics of the HFV are modeled.The coupling dynamics of the HFV are analysed based on the model,and the analyses mainly involve the following aspects: the attitude and trajectory,the three channels of attitude,the attitude and aerodynamic force,the control surface and trajectory,and the attitude and propulsion system.Secondly,a coordinated controller is designed for the longitudinal channel of the HFV.A coupling analysis is accomplished to the effect between the group of state variables and input variables based on the statistical sampling coupling analysis method.A hierarchical coordinated controller of the longitudinal system is designed through the combination of the coupling matrices obtained from the coupling analysis and the sliding mode control method.Then,on the basis of research fruits of the longitudinal coordinated control,the longitudinal robust coordinated controller is designed,which is to solve the problems such as strong coupling,uncertainty,and thrust vectoring.The coupling relationships between the longitudinal variables are analysed from the model point,and then the problem of strong coupling is solved by combining the coupling matrices and the terminal sliding mode control method.The uncertainties of the system are approximated by a nonlinear disturbance observer.The coordination problem between the thrust vectoring control surfaces and the pneumatic control surfaces is solved by designing the weighted energy optimal performance index.Subsequently,a coordinated controller is designed for the attitude system of the HFV.The coupling analyses of attitude angles,attitude angular rates,attitude angles and attitude angular rates and attitude angular rates and control surfaces are accomplished based on the statistical sampling coupling analysis method.Then,the coordinated controllers for the attitude angle subsystem and attitude anglar rate subsystem are designed respectively by combining the coupling matrices and the sliding mode control method.Finally,considering the uncertainties and the thrust vectoring problems of the attitude system,a robust coordinated controller is designed.The coupling relationships of the variables in the attitude model are analysed,and then the negative impact of the strong coupling is eliminated by combining the coupling matrices and the terminal sliding mode control method.The nonlinear disturbance observers are designed for the attitude angle subsystem and attitude anglar rate subsystem respectively in order to approximate the uncertainties of the each subsystem.The weighted energy optimal performance index is designed for two thrust vectoring control surfaces and three pneumatic control surfaces to solve the coordination problem of control surface.