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In this article, a distributed adaptive fault-tolerant control scheme is presented for the attitude consensus of multiple flexible spacecraft formulated by partial differential equations (PDEs). Each spacecraft is supposed to be actuated by a control torque on the rigid hub and a control force on the tip payload. First, a finite-time distributed observer is constructed to estimate the virtual leader's state for each follower spacecraft under local communication. Then, an individual controller is exploited for each follower spacecraft, which consists of an adaptive boundary control torque law to track the recovered attitude and velocity and an adaptive boundary control force law to eliminate the elastic deformation. Particularly, the parametric adaptation laws are incorporated to compensate the actuator faults and perturbations. The attitude synchronization errors, velocity synchronization errors, and elastic deformations can asymptotically stabilize to zero under the introduced controller. This work owns the following two major novelties. One is introducing a unified distributed control framework for the PDE-based attitude consensus of multiple flexible spacecraft. Another is developing a novel parametric adaptation strategy to accommodate the actuator faults. Lastly, comparative simulations verify and highlight the main results. [ABSTRACT FROM AUTHOR]

This article presents a prescribed performance adaptive control scheme for the attitude tracking and vibration reduction of flexible spacecraft modeled by partial differential equations (PDEs). First, the original constrained problem is converted to an equivalent unconstrained one by adopting a prescribed error transformation. Then, a boundary control torque law and a boundary control force law are developed to track the desired attitude and reduce the vibration, respectively. Moreover, the parametric adaptation technique is integrated with the boundary control laws to estimate the disturbances. The closed-loop system is evaluated to be asymptotically stable through the Lyapunov stability theorem and LaSalle's invariance principle. The developed controller has two distinctive features as follows. One is the controller can guarantee the attitude tracking error and tip deformation always satisfy the prescribed performance constraints. Another is the controller can acquire the strong robustness owing to the feedforward disturbance compensation. Lastly, the derived results are demonstrated by simulated studies. [ABSTRACT FROM AUTHOR]