Research On Fault Tolerant Control For Thrust Vector Aircraft

Thrust vector technology can make aircraft to realize control surface redundancy and to improve the flight performance of aircraft. Therefore, the technology has been paid more and more attention by the world’s military powers, and the design of flight control system becomes more complicated. The design of control law on the control surface deflection combination has great significance for making aircraft control surface to optimize configuration and making the best use of redundancy control surface under the situation of control surface failure. The main work of this paper is as follows:Firstly, the nonlinear mathematical model of thrust vector aircraft was established. aircraft open loop zero input response, channel coupling characteristic and external torque distraction were analyzed, and the accuracy of the established aircraft model was verified.Secondly, aiming at external direct torque distraction and system inversion error when flying, dynamic inversion controller based on sliding-mode observer and fuzzy tuning PI was designed. And, simulation carried out to compare the design controller and the traditional nonlinear dynamic inversion controller through adopting cobra maneuver, a typical super-maneuverable movement, and verified the effectiveness and superiority of the designed controller.Thirdly, the control surface failure of thrust vector aircraft was modeled, fault-tolerant control law based on the pseudo inverse control allocation and the concatenated chain control allocation were respectively designed. Furthermore, simulation was respectively carried out on the two situations of the horizontal direction rudder control surfacepart failure and the stuck, and the superiority of these two kinds of fault-tolerant control law was verified.At last, because the dynamic property of thrust vector control actuator is different from the traditional control actuator, the dynamic control allocation method of the thrust vector aircraft was mainly researched. Then the dynamic control allocation algorithm and the dynamic fault-tolerant control allocation algorithm under the situation of control actuator failure were proposed. The simulation result indicated that comparing to the traditional static control allocation algorithm, the dynamic control allocation algorithm has a better attitude angle tracking performance; under the situation of actuator failure, dynamic fault-tolerant control allocation algorithm can effectively improve the quality of the aircraft attitude angle tracking.