Adaptive Discrete Time Dynamic Surface Control for Aircraft Flight Path Angle with Unknown Disturbances

Abstract

Aiming at the problem of tracking control system of the aircraft flight path angle, an adaptive discrete time dynamic surface control algorithm is proposed. Firstly, introducing the concept of discrete time system, the sampling signal form used is easy to suppress noise, and the impact of delay on the system is reduced through sampling. Afterwards, the dynamic surface control and the first-order digital low pass filter is introduced which making both controller and parameters easier and avoiding differential explosion in traditional backstepping method. Furthermorethe RBF Neural Network is introduced to approximate the unknown parameters and uncertain items in the system and the unknown interference part of the externa, which reduces the requirements on the system and structure. By using the Lyapunov function theory, it is proved that the closed-loop system is semi-globally ultimately uniformly bounded. Finally, simulation verification is performed and the results show that the proposed control algorithm can not only make the flight path angle track the reference trajectory, but also has a certain degree of robustness to unknown system parameters and unknown external interference.