Active Control Of Low-sonic Velocity Nonlinear Aeroelasticity Wing

In this paper, with the nonlinear aeroelastic two‐dimensional airfoil as the research target, the active flutter control of nonlinear aeroelastic airfoil is researched, which is used to suppress the flutter problem of aircraft due to aerodynamics, elasticity, inertia and other various factors and improve the stability, mobility and safety of airplane.Main research contents in this paper: the nonlinear aeroelastic two‐dimensional airfoil model and its kinematic equation are deduced, its open‐loop response, balance point, flutter critical speed and time response diagram are analyzed. Then, the slide model control theory and fuzzy control theory are researched and analyzed, their concept, principle, characteristics, design method, existing problems, notes and focus are carefully analyzed, on the basis of designing the simple system, with the complex airfoil system as the target, a controller is designed, the initial instability state is given, simulated in Simulink, its time response is recorded, compared with the ordinary adaptation control, and it is concluded that fuzzy sliding mode control(FSMC) can effectively suppress flutter. Second, the RBF artificial neural network is researched, and in combination with the sliding mode control, with the complex airfoil system as the target, a neural sliding mode controller is designed, and simulated in Simulink, with a good simulation result, and its control stability and timeliness are compared with FSMC. Finally, the summary and prospect are made.The motion state of the airfoil is discussed by deducing, calculation and analysis, a corresponding controller is designed and simulation debugging is conducted to effectively suppress the flutter. A fuzzy sliding mode control(FMSC) based method is proposed to solve the problems of ups and downs of nonlinear aeroelasticity and flutter of two‐dimensional airfoil. Meanwhile, neural sliding mode control method(NSMC) is discussed as the active control method to solve the flutter problem of low sound velocity airfoil and compared with the FSMC method, the latter has a better stability and convergence. These advantages, when presented in airplane, are that the airplane has a stability against the strong airflow, can well suppress the flutter timely, so as to guarantee the airplane safety maximally.