Coupling-Characterization-Based Robust Attitude Control Scheme for Hypersonic Vehicles

The issue of couplings makes the attitude control design for hypersonic vehicles (HSVs) challenging. This paper focuses on the characterization of coupling and its application in the control system synthesis. A novel coupling characterization index is introduced via the Lyapunov stability theory to indicate whether a coupling harms or benefits the system. The control scheme is designed to eliminate the detrimental couplings while keeping the beneficial couplings. The novelty of this paper is that the system couplings are explicitly utilized in the controller design leading to better dynamic performance. The robustness of the proposed controller is enhanced by using a disturbance observer. The effectiveness of the proposed scheme is validated by simulations in the HSV attitude system.