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This study proposes an integrated fault estimation (FE) and fault‐tolerant control design for a rigid spacecraft attitude system with inertia uncertainties, external disturbances, input saturation, and different type multiple actuator faults. A barrier function is first introduced to eliminate the effects of inertia uncertainties and disturbances in the design of the sliding mode FE observer. By using the non‐singular fast terminal sliding mode control technology, a finite‐time fault‐tolerant attitude stabilisation controller and a finite‐time fault‐tolerant attitude tracking controller are designed to guarantee that the closed‐loop attitude system has a good fault‐tolerant performance under actuator faults. Furthermore, when considering actuator saturation, an auxiliary system is utilised to compensate for the saturation. The stability of the closed‐loop system is analysed by Lyapunov theory. Finally, the effectiveness of the proposed control approach is demonstrated via simulation results. [ABSTRACT FROM AUTHOR]

This study investigates the active fault tolerant control (FTC) problem for the attitude system of a rigid satellite, which is affected by parameter uncertainty, unknown exogenous disturbance and actuator time‐varying faults. The upper bounds of the actuator time‐varying fault and the generalised perturbation are unknown. A novel adaptive non‐linear fault estimation observer is designed in order to obtain the estimated value of unknown time‐varying faults. Then, an active fault tolerant attitude control approach is proposed under the framework of both backstepping control and adaptive control theory. Consequently, the Lyapunov theory is used to prove the robust asymptotic stability for the closed‐loop attitude system of a faulty satellite under the proposed FTC scheme. Finally, simulation results on an in‐orbit rigid satellite are provided to show the good fault tolerant performance, which validate the effectiveness and feasibility of the proposed scheme. [ABSTRACT FROM AUTHOR]