Finite-time decoupling direct control for hypersonic reentry vehicle with multiple disturbances via second-order ADRC

Abstract

In this paper, a novel finite-time decoupling direct control (FDDC) scheme is proposed for attitude tracking problem of hypersonic reentry vehicle (HRV) based on second-order active disturbance rejection control (SADRC). Unlike traditional control method which separates control system into outer-loop attitude control and inner-loop angular rate control, attitude is controlled by control actuator straightforward with single loop. Firstly, the attitude tracking problem is converted to the decoupling control problem of a three-input and three-output cross coupling system. In each channel, a SADRC controller, which is composed of tracking differentiator (TD), extended state observer (ESO) and nonlinear state error feedback (NLSEF), is designed to track attitude command of the corresponding channel in a finite-time sense. Finally, the obtained virtual control input is transformed into actual control input, which acts on the HRV model. Simulations are conducted to verify the effectiveness of the proposed control scheme.