Design of Finite-Time Attitude Control System for Reentry Vehicles Based on Extended Observer

This paper takes the hypersonic reentry vehicle as the research object, and completes the design of the finite time attitude control system based on the extended state observer. First, a control-oriented mathematical model of the aircraft is established to lay the foundation for the subsequent control system design; then a variable gain finite time extended state observer is designed based on the finite time convergence theory to complete the real-time observation of the disturbance; then a finite time convergence attitude controller was built using the integral terminal sliding mode surface to achieve good attitude control; a dynamic control allocation scheme based on quadratic programming is designed to ensure the optimal solution of the actuator deflection angle, while avoiding the saturation of the actuator. Finally, a numerical simulation of the aircraft control system is performed. The results show that the control scheme outlined in this paper has fast convergence speed, high tracking accuracy, and nice control performance.