Direct lift carrier landing method based on predefined-time active disturbance rejection control

This paper proposes a predefined-time active disturbance rejection control-based direct lift control scheme with a predefined-time extended state observer for carrier-based aircraft to address the issue of landing safety during carrier landing process and to improve transient response, flight performance and robustness. First, a six degree-of-freedom nonlinear model is established for the carrier-based aircraft and the combination mechanism of direct lift control surface and aerodynamic surface is analyzed. Then, a novel predefined-time stable extended state observer is presented to accelerate disturbance estimation and avoid chattering caused by high-gain coefficient, whose predefined-time stability is proved based on Lyapunov stability theory. Subsequently, a novel predefined-time stable active disturbance rejection controller is designed, which ensures that the aircraft tracks command signals within a user-defined convergence time and suppresses the effect of carrier air wake turbulence. Moreover, the predefined-time stability of the closed-loop system is analyzed. Finally, both numerical simulations and real-time simulation experiments are conducted to verify the effectiveness and practicality of the designed predefined-time active disturbance rejection control-based direct lift control scheme.