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The neural tracking control problem for nonlinear strict-feedback multi-agent systems (MASs) subject to actuator faults in finite-time is considered, where each agent communicates with its neighbours on a time-varying directed topology. Radial basis function neural networks (RBFNNs) are used to approximate the unknown internal dynamics of system. By utilising backstepping method and dynamic surface control (DSC) technique, a novel adaptive fault tolerant controller is put forward. It turns out that the designed controller can compensate the effect of uncertainties and actuator faults. Meanwhile, by constructing piecewise Lyapunov functions, sufficient conditions for dwell time of topologies are given such that system achieves finite-time tracking consensus under the designed controller. Finally, an example is carried out to verify feasibility of the theoretical result. [ABSTRACT FROM AUTHOR]

This paper addresses H ∞ leader-following consensus of multi-agent systems with semi-Markovian switching topologies and time-varying delays. Unlike the classic Markovian switching topologies, the transition rates are time-varying in the semi-Markovian switching topologies, which can better model the switching of topologies due to inevitable stochastic changes. Moreover, compared with existing works on multi-agent systems with switching topologies and time delays, the delays in the paper are dependent on the switching modes. By designing the distributed mode-dependent consensus protocol and constructing Lyapunov functional, sufficient conditions in terms of LMIs are derived to ensure that H ∞ leader-following consensus is asymptotically achieved in the mean square. Finally, a numerical example is provided to show the effectiveness of the main results. [ABSTRACT FROM AUTHOR]

This paper investigates the containment control problem of multi-agent systems with semi-Markovian switching topologies. Different from the related works, this paper considers a more general case that the control inputs of leaders are nonzero, the sojourn time distributions of the semi-Markovian switching topologies are mode transition-dependent, and the states of agents are not measurable. Reduced-order observer-based control protocols are proposed, respectively, for two cases that the transition rates are completely known and partially unknown, which ensures that the containment of the multi-agent systems can be achieved in the mean square sense. Finally, simulation examples are given to illustrate the validity of the theoretical results. [ABSTRACT FROM AUTHOR]

Summary: This article investigates the leader‐following consensus of nonlinear multiagent systems under semi‐Markovian switching topologies and cyber attacks. Unlike the related works, the communication channels considered herein are subjected to successful but recoverable attacks, and when the channels work well, the network topology is time‐varying and described by a semi‐Markovian switching topology. Due to the effect of attacks, the communication network is intermittently paralyzed. For the cases that the transition rates of semi‐Markovian switching topologies are completely known and partially unknown, observer‐based control protocols and sufficient conditions are proposed, respectively, to ensure the consensus of the systems in the mean square sense. Finally, simulation examples are given to illustrate the validity of the theoretical results. [ABSTRACT FROM AUTHOR]

Summary: The containment control of stochastic multiagent systems with semi‐Markov switching topologies is investigated in this paper. The general case that the distribution function of the sojourn time is dependent on both the current system mode and the target mode is considered. Taking state multiplicative noise into account and using stochastic techniques, sufficient conditions to achieve the containment control in the asymptotic mean square sense are obtained in a form of linear matrix inequalities and the controller design condition is given. Finally, a simulation is given to demonstrate the effectiveness of the obtained theoretical results. [ABSTRACT FROM AUTHOR]

Second-order consensus of multi-agent systems with noises via intermittent control is investigated in this paper. First, we study the mean-square consensus problem with communication noises by intermittent control. In order to reach consensus, under the strong directed interacted topology, by using the tools of graph theory and Lyapunov method, a distributed control protocol is proposed based on the noises and periodical intermittent information. The upper bound of noise strength in the sense of matrix norm and the lower bound of communication time duration are obtained. Second, a class of coupled system models which include delay-terms in their nonlinearities in the noisy environment is discussed. Under the balanced strongly connected topology, the sufficient conditions to achieve the mean-square average-consensus are obtained. Finally, simulations are given to illustrate the effectiveness of our results. [ABSTRACT FROM AUTHOR]

This paper studied the impulsive consensus of stochastic multi-agent systems (MASs) under semi-Markovian switching topologies. The semi-Markovian process is employed to describe the random changes of communication topologies among agents. Applying the impulsive control method, the communication among agents is only needed at impulsive control instants. For the connectivity of communication topologies, we only require that partial communication topologies contain a directed spanning tree, which remove the restriction that every communication topology contains a directed spanning tree in existing works. Using the Lyapunov function method and the stationary distribution of semi-Markovian process, the impulsive control protocol (ICP) is designed to ensure the almost surely exponential consensus of stochastic MASs. As an application, the obtained result is used to solve the secure impulsive consensus of stochastic MASs under random cyber-attacks. We proposed a novel model of random cyber-attacks, in which adversaries can destroy communication links of agents and durations of attack-active interval and attack-free interval are random variables. A simulation example is given to show the effectiveness of obtained results. [ABSTRACT FROM AUTHOR]

Leader‐following consensus is investigated for second‐order continuous‐time multi‐agent systems with limited communication data rate in this study. The network communication topology is directed and static. Using the sampled position and velocity data, a corresponding discrete‐time system, whose leader‐following consensus is proved to be equivalent to that of the original system, is given. A distributed protocol is proposed based on dynamic encoding and decoding. A necessary and sufficient condition is given for the existence of such communication and control protocol to ensure the achievement of leader‐following consensus, if the upper bound of the communication data rate is predetermined. Two algorithms are also presented to achieve the leader‐following consensus if the communication data rate is unfixed or limited, respectively. Finally, simulation examples are given to verify and illustrate the theoretical analysis. [ABSTRACT FROM AUTHOR]

In this study, the authors investigate L2 − L∞ containment control problem of multi‐agent systems with multiple stationary leaders and external disturbances. Furthermore, the interaction topology is Markovian switching and non‐uniform time‐varying delays are considered. By using a model transformation, the containment control problem of the multi‐agent systems is turned into a normal L2 − L∞ control problem. Based on the theory in stochastic stability for time‐delays systems, sufficient conditions in terms of a set of linear matrix inequalities are given to ensure that all the followers will move into the convex hull formed by the leaders in mean square sense with a prescribed L2 − L∞ performance. Two numerical simulations are provided to show the effectiveness of theoretical results. [ABSTRACT FROM AUTHOR]