Research On Trajectory Tracking Control Of Wave-rider Hypersonice Cruise Vehicle

Air-breathing hypersonic vehicles (AHSV) have been considered to be the mostpromising and cost-effective technology in both commercial and military areas due toits incomparable maneuverability and "prompt global strike" capability. More and moreresearches have been increasingly conducted on AHSV around the world in recent years.This paper focuses on cruise control of wave-rider hypersonic vehicle based on the fullknowledge of the recently study status about AHSV at home and abroad. The maincontents are as follows.Based on the sphere earth model, the nonlinear six degree-of-freedom (DOF)model is established based on Newton’s second law and momentum theoremconsidering the influence of the earth’s rotation. After the flexible airframe is idealizedas an Euler beam, the vibration model of AHSV is established. In the end, thelongitudinal model of AHSV is obtained in zero-sideslip roll maneuver.The nonlinear longitudinal model of AHSV is linearized on the condition of littleperturbation. The Linear parameter varying (LPV) model is established on the basis ofmodal analysis, and the dynamic characteristics are researched. Then the study subjectsare proposed, such as saturation of control surface, servo elasticity problem of AHSV,path-attitude decoupling and the large-span maneuver flight control.Both the anti-windup compensators based on L2gain and LMI are designed to dealwith the saturation problem of control surface, especially the fully analysis of thestability of L2anti-windup compensator and the simplified form of the control law aregiven in this paper. To solve the servo elasticity problem of the flexible vehicle, twomethods based on notch filter and rate gyro placement is provided. Besides, to handlethe path-attitude decoupling problem, a controller design method is proposed usingcanard coordinated with the elevator.Given the trajectory tracking problem of the vehicle with large-span maneuver,firstly, the nonlinear longitudinal model of the vehicle is linearized and decoupled withdynamic inversion method. Then the LQR controller is designed, and the sliding modecontroller is provided further to handle the control performance deterioration due to themodel uncertainty. Secondly, the angle of attack (AOA) and the flight-path angle maybe difficult to measure when the vehicle flies at a small AOA; therefore the nonlinearsliding mode observer is designed to estimate them. Finally, the notch filter is used tosolve the servo elasticity problem of the nonlinear flexible vehicle.