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This article investigates the output fault‐tolerant consensus problem for multi‐agent systems with switching topology and deception attacks. In order to reduce the effects of switching topology, the differences between topologies can be modeled as topology uncertainties. In practice, the deception attack may occur in a random way and assumed to satisfy Bernoulli distributions. The purpose of this research is to design an output fault‐tolerant controller such that, in the presence of switching topology, actuator faults, and deception attacks, the finite‐horizon output fault‐tolerant consensus can be achieved under a prespecified H∞$$ {H}_{\infty } $$ performance. An initial‐state‐based performance requirement is constructed, and this bypasses the need for the zero initial condition in the conventional H∞$$ {H}_{\infty } $$ theory. After this, the controller gains are computed by employing an iterative linear matrix inequality scheme. Finally, a numerical example is provided to show the effectiveness of the proposed methods. [ABSTRACT FROM AUTHOR]

Summary: This article studies a kind of asynchronous fault‐tolerant control problem for stochastic systems (Markov jump systems, MJSs) with multiple‐types of actuator failures. Both the loss of effectiveness and stuck fault of actuator are taken into consideration in a unified actuator failures model. The asynchronization phenomenon between the controller and the original system is described by a hidden Markov model. By coupling the unknown stuck fault of actuator and the external disturbances together, the stuck fault and disturbance can be estimated simultaneously. After this, a fault‐tolerant controller based on the estimated values is designed further to automatically compensate for the faults while preserving the uniformly ultimate boundedness of the solutions. Moreover, a mode‐dependent adaptive event‐triggered mechanism is introduced to limit the number of packets sent on the network. Finally, a numerical example is employed to illustrate the effectiveness of the proposed design scheme. [ABSTRACT FROM AUTHOR]

Summary: In this paper, mixed passive / H∞ hybrid controllers are designed for a delayed Markovian jump system with actuator constraints and alarm signal. The actuator constraints include the unknown actuator bias failure and the actuator partial failure, and the controllers are switched by using alarm signals. First, a sufficient condition for mixed passive / H∞ performance of the closed‐loop system is constructed, and robust controllers and fault‐tolerant controllers are designed, respectively. Then, mixed passive / H∞ observers are presented to ensure that the actuator bias failure is well estimated. Next, an alarm system is proposed by designing multiple thresholds to avoid false alarm, and this system is used to invoke suitable controllers and determine whether to remove the estimated value of actuator bias failure. Finally, two numerical examples are given to illustrate the effectiveness of the method. [ABSTRACT FROM AUTHOR]

In this study, the synchronisation problem of bilateral teleoperation systems with time‐delay and actuator faults is considered. First, the error dynamic system with actuator faults is modelled as a time‐delay system with disturbance, and a fuzzy disturbance observer (FDO) is designed to estimate the unknown non‐linear disturbance. Moreover, an FDO‐based robust controller is provided for the master robot and a reliable controller is designed for the slave robot, respectively. Next, a sufficient condition is given to ensure the tracking error; the disturbance observation error and the parameter error are uniformly ultimate bounded. Finally, a numerical example is shown to illustrate the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]