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This paper provides a new solution for the finite‐time attitude maneuvers of rigid spacecraft. Uncertainties involving unknown inertial parameters, external disturbances and actuator failures are taken into account. With an effort to achieve attitude tracking despite the impact of uncertainties, a non‐singular terminal sliding mode (NTSM) manifold consisting of attitude errors and angular velocity errors is first constructed. After that, a simple but efficient adaptive updating law is derived to estimate the upper bound of the lumped unknown function in the derivative of sliding surface. Combining NTSM technology and pure adaptive control, a chattering‐free fault‐tolerant controller is presented. The premise assumptions on uncertainties in most of the existing achievements are eliminated, which makes the controller less constrained and more practical. The rigorous proof of finite‐time stability is provided and the convergent regions of tracking errors are explicitly expressed. Finally, numerical simulation is conducted to verify the effectiveness of the proposed control scheme and the comparison experiments with relevant literature demonstrate the satisfactory performances. [ABSTRACT FROM AUTHOR]

Summary: In this article, the problem of finite‐time attitude‐tracking control for rigid spacecraft is addressed. Uncertainties caused by external disturbances, unknown inertial matrix, actuator failures, and saturation constraints are tackled simultaneously. First, a smooth function that is more qualified to approximate the standard saturation characteristics is presented to deal with the actuator saturation constraints. Second, a fast nonsingular terminal sliding mode (FNTSM) manifold is constructed as a foundation of controllers design. By incorporating the fuzzy logic system into FNTSM technique, a less demanding solution of coping with model uncertainties is provided because the requirement of a prior knowledge of unknown inertial parameters and external disturbances in many existing achievements is removed. To reduce the number of parameters to be estimated, the norm approximation approach is exploited. Subsequently, an antichattering attitude controller is presented such that all the tracking errors converge into arbitrary small domains around the origin in finite time. The result is further extended to obtain a fault‐tolerant controller against completely failed actuators. Finally, numerical simulation is conducted to verify the effectiveness of the proposed control scheme and comparison with relevant literature demonstrates its high performance. Furthermore, an experiment for the large satellite Hubble Space Telescope is carried out to validate the practical feasibility. [ABSTRACT FROM AUTHOR]