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.

In avionics and aerospace multisensor systems, reliable and early detection of individual sensor faults present substantial challenges to health monitoring designers of such systems. This study addresses the problem of sensor fault diagnosis. The proposed solution is based on a non‐homogeneous high‐order sliding mode observer used to estimate the faults, theoretically in finite time and in the presence of bounded disturbances. The sensor faults are estimated for the class of systems satisfying the structural property of strong observability. A key feature of the proposed solution is concerned by the effect that measurement noise could have on fault reconstruction. It is shown that the fault estimation error is bounded in the L _∞ ‐norm sense, and an upper bound is theoretically derived. The method is applied to the problem of sensor fault estimation of a large transport aircraft. Simulation results as well as a pilot experiment are presented to demonstrate the potential of the proposed method.