Microsoft Word - 136

-The scramjet performance of air-breathing hypersonic vehicle is highly correlated with flight height, Mach and angle of attack (AOA). The violent disturbance of the AOA can cause the engine power off. Consequently, the maneuverability of hypersonic vehicle is strictly limited in the cruising period. A composite control system for an air-breathing hypersonic vehicle is presented. The hypersonic vehicle has a configuration with tailcontrol rudders and a set of deflectable wings installed nearby the center of gravity. During the cruising period, the precision of AOA is achieved by deflecting tail rudders, and the command of maneuverable acceleration is tracked by deflecting wings. In the period of endgame, the scramjet should be power off, and the limit of AOA does not exist, so the tail rudders and the wings can both deflect to achieve high maneuverable acceleration. A linear quadratic (LQ) track control algorithm with integrator is introduced to design the composite control system. Simulation results demonstrate that the composite control system has good performance in tracking AOA and acceleration command by respective deflection of tail rudders and deflectable wings in cruise and also can track high acceleration command by coincident deflection during endgame. Keywords-composite; hypersonic; vehicle; wing; rudder