Robust intelligent control of aircraft at high angle of attack maneuvers using monitoring mechanism

Considering the characteristics of strong nonlinearity, aerodynamic uncertainty and channel coupling of aircraft at high angle of attack (AOA) maneuvers, this paper studies the robust adaptive control based on monitoring mechanism. By treating channel coupling as part of the total disturbances, the flight dynamics is decomposed into the AOA, sideslip angle and roll rate subsystems. For each subsystem, a robust intelligent controller that utilises error feedback and estimation feedforward is designed to achieve desired control moments. Subsequently, the deflections of aerodynamic control surfaces and thrust vector nozzles are calculated using the daisy-chain method. Neural networks are employed to estimate aerodynamic uncertainties, while prediction errors are constructed to design composite update laws. Furthermore, the monitoring mechanism is designed to assist the controller drag flight states back to the boundaries. The uniformly ultimately bounded stability is analysed based on Lyapunov approach. Simulation tests demonstrate that the proposed method provides enhanced tracking performance.