Research On Backstepping Control For Hypersonic Flight Vehicle

With the development of science, air and space technology plays more roles in the modern war. Specially, hypersonic flight vehicle technology will become a hot spot in aerospace technology in the future. However, due to the characteristics of nonlinear, strong coupling and time-varying in the hypersonic vehicle systems, the control algorithms will directly affect its flight performance. To ensure the flight control algorithms stable, this paper studies the issues of hypersonic aircraft flight control, especially for the longitudinal model control issues and six-degrees-freedom model attitude control issues, the main contents are as follows:(1) A six degrees-of-freedom of a hypersonic flight vehicle kinematics model is established. The model built in this paper reflects the characteristics of nonlinear, strong coupling and fast time-varying in hypersonic flight vehicle. Moreover, the function of correlation coefficient of aerodynamic,angle of attack and Mach number are analyzed to provide a platform for the design of the subsequent control algorithms.(2) The backstepping control algorithm for longitudinal model is designed. Firstly, based on the established the six degrees-of-freedom model, the hypersonic vehicle longitudinal motion models of both without loss of generality and simplify is established by simplifing the corresponding factors. Secondly, the longitudinal model is decomposed into velocity subsystem and altitude subsystem, the two subsystems are transformed into the strict-feedback forms. Then, the backstepping controller are designed on the basis of the strict-feedback forms. The simulation results show that the control algorithm owns good tracking performance.(3) The backstepping control algorithm for six degrees-of-freedom model is designed. Firstly, the open-loop characteristics of the system is analysed, and the simulation results show that the state of the system becomes divergence without the input signal. Secondly, A nonlinear affine model is established, which can be used to design control system. On the basis of this model backstepping controller is designed, the simulation results show that the designed controller stable tracking a given gesture command signal.(4) The adaptive backstepping control algorithm for six degrees-of-freedom model is designed. For hypersonic flight vehicle parameter uncertainty control problems, by combining with adaptive and backstepping method, controller with adaptive parameters is designed, and the simulation results show that the controller has good robustness and adaptability. Moreover, the achieve a hypersonic flight vehicle achieves stability control under conditions of uncertainty attitude.