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.

This article studies the adaptive fault tolerant control (AFTC) and collision avoidance problem for wheel mobile robots (WMRs) under event-triggered mechanism and communication constraints. The dynamics of WMRs and their transformation are considered first. To handle the constraint that only part of the robots can access the leader, the distributed state estimators are designed. Simultaneously the actuator faults and external disturbances are approximated by cerebellar model neural network. Then, an event-triggered-based AFTC and collision avoidance scheme is developed by utilizing a backstepping control technique and artificial potential field. The stability of the closed-loop system is proved and Zeno behaviors are excluded. Finally, the simulation evaluation and experimentation of three robots is implemented to illustrate the superiority of the presented scheme.