Research On Robust Adaptive Multiple Model Control Of Hypersonic Vehicle With Aero-elastic Effect

Hypersonic vehicle occupies an important position in the field of aerospace technology because of its high flight speed and wide flight scope.However,compared with conventional aircrafts,the flight environment,structural material,fuselage coupling,and elastic mode of hypersonic vehicles bring serious problems of parameter uncertainties to the design of flight control system.Therefore,in order to design a safe and effective flight controller,the influence of parameter uncertainties must be fully considered in the design process to ensure both the good flight performance and the strong robust performance.In view of the above problems,this paper mainly researches the design of flight controller in the presence of elastic modes and serious parameter perturbations.The main research contents are as follows.Firstly,based on the existing parameters of a hypersonic vehicle model,a rigid six-degree-of-freedom dynamic model is established.Analyzing the elastic modes of the hypersonic vehicle,a longitudinal nonlinear elastic model of the hypersonic vehicle is established.Main uncertain parameters in the model are further analyzed,and an uncertain linear model expression is given,which lays the foundation for the design of controllers and switching controllers in the following sections.Secondly,a robust controller for an elastic hypersonic vehicle based on m-synthesis is designed for the system with effects of parameters uncertainties and elastic modes.The elastic modes are handled as uncertainties,and then an open-loop internal connection structure is constructed for the uncertain system,in which appropriate performance weighting functions are selected.Based on the D-K recursive design method,a ?-synthesis robust controller is designed.The simulation results and comparative analysis of the control performances under different parameter ranges are given,thus introducing the design requirements of the mixing controller.Then,to handle the system with serious parameters perturbations,the uncertain parameters with wide range are divided to be multiple sub-models.Several ?-synthetic robust sub-controllers are designed for each sub-model separately,based on which an adaptive mixing controller is then designed.The mixing strategy and robust adaptive parameter identifier are designed respectively.Based on these,a YJBK parametric multi-model mixing controller is designed.The simulation results show that the mixing controller can effectively solve the flight control of hypersonic vehicle under severe parameter perturbations.Finally,considering the limitation of linear control method,a nonlinear adaptive super-twisting sliding mode controller is designed.Unlike the design process of the ?-synthetic robust controller,the elastic modes are taken as the state variables here,and the exact feedback linearization model is established.The design process of the control law,the adaptive law and the stability proof of the control system are given.The simulation results show the effectiveness of the adaptive super-twisting sliding mode controller.