The Research And Design Of Backstepping Control Method In Flight Control

With the rapid development of science and technology, modern war demands for ahigher aircraft, aircraft must have the capabilities of high-speed, hidden, mobility, and thusaircraft is a nonlinear, time-varying strong coupling system, this is a higher challenge forcontroller design.Using the idea of virtual control, backstepping control construct the entire systemLyapunov function step by step recursively according to the structural properties of thesystem, there is lots of flexibility in selecting the Lyapunov functions and controllerdesign, by choosing an appropriate Lyapunov function and design parameters, the systemtransient response could be enhanced greatly. Because of its unique structure of the designprocess and the capabilities of dealing with non-matching uncertainty, backsteppingcontrol design methods has been successfully applied in aircraft, missiles, electronics,robotics.This thesis introduces the basic backstepping control algorithm, discusses the designof backstepping controller in the hypersonic vehicle and BTT missiles. Firstly, accordingto the characteristics of hypersonic aircraft longitudinal model, the longitude equationsmeets the strict feedback form, the backstepping method is used to design controller.During the aircraft flight, there exists parameter perturbation, the external disturbance,unmodeled dynamics and uncertainties, in order to ensure system accuracy, neuralnetworks are used to approximate unknown nonlinear functions, the neural networkadaptive backstepping controller are designed to improve the robustness of the system.In BTT missile, there is pitch, yaw, roll three channels, thus can be seen asinterconnected systems composing of three subsystems, decentralized control is used todesign controller, backstepping control is used for each subsystem, a neural networkadaptive controller is designed.A series of simulation are made for the designed controllers, the simulation results demonstrate that the control system is stable and robust.