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This paper investigates the distributed event-triggered consensus tracking control problem for nonlinear multi-agent systems in the presence of intermittent attacks on both intra- and inter-agent communication channels. Intermittent attacks are characterised by their ability to manipulate the channel transmission factor to disrupt the reliability of communication. First, to address the problem that the agent model knowledge is unknown, a dynamic linearisation method is introduced to transform the nonlinear agent models into equivalent linear models that depend only on the agents' input and output data. Then, a dynamic event-triggered mechanism is developed to reduce communication transmission, which is based on individual agent information rather than consensus errors to avoid the impact of attacks occurring in the communication between agents. Building upon the attack model and the equivalent linear data model, a distributed model-free adaptive control scheme with dynamic event-triggering is devised to ensure that the consensus errors of all agents are ultimately bounded, even when intermittent attacks occur. The proposed scheme's effectiveness is demonstrated through numerical simulation. [ABSTRACT FROM AUTHOR]

The problems of prescribed-time leader-following consensus and prescribed-time containment control for double-integrator multiagent systems (MASs) with only position measurements are investigated in this paper. An observer-based prescribed-time control protocol is proposed, in which the two groups of observers for estimating the consensus errors of each follower both converge to zero within a specified time. Furthermore, the proposed controller only relies on its own observers and does not need to obtain the data from observers embedded in its neighbor nodes. The sufficient conditions for the MASs to achieve the defined prescribed-time consensus and to fulfill the goal of prescribed-time containment control are, respectively, given. The effectiveness of the proposed control protocol is further verified by computer simulations. [ABSTRACT FROM AUTHOR]

In this paper, the optimal formation control issue with collision avoidance and connectivity assurance is investigated for a class of second-order uncertain nonlinear multi-agent systems. First, the neural networks are employed in order to deal with the unknown nonlinear dynamics of the system. Then, an optimal formation control scheme is developed in the framework of the identifier–actor–critic. By constructing a new performance metric function containing collision avoidance and connectivity constraints, it is demonstrated that asymptotic convergence of the tracking error can be achieved under the proposed control scheme. Finally, the effectiveness of the proposed control method is validated by the numerical simulation example. [ABSTRACT FROM AUTHOR]

This paper focuses on studying the optimization problem of multi-agent systems (MAS) under undirected graph. To reduce the communication frequency among agents, a zero-gradient-sum (ZGS) algorithm based on dynamic event-triggered (DET) mechanism is investigated. The event-triggered condition of each agent only uses its own state information and the neighbor's state information at the previous triggering instants, without requiring continuous state information from the neighbor. In addition, the designed algorithm allows for the sampling period to be arbitrarily large. The Lyapunov method is utilized to derive the sufficient conditions that incorporate time delay and parameters. As the event is only checked at the periodic moment, zeno behavior can be directly excluded. Finally, numerical simulations demonstrate the effectiveness of the theoretical results. [ABSTRACT FROM AUTHOR]

In this paper, the asymptotic consensus control of multi-agent systems with general linear agent dynamics is investigated. A neighbor-based adaptive event-triggering strategy with a dynamic triggering threshold is proposed, which leads to a fully distributed control of the multi-agent system, depending only on the states of the neighboring agents at triggering moments. By using the Lyapunov method, we prove that the states of the agents converge asymptotically. In addition, the proposed event-triggering strategy is proven to exclude Zeno behavior. The numerical simulation results illustrate that the agent states achieve consensus in sense of asymptotic convergence. Furthermore, the proposed strategy is shown to be scalable in case of variable agent numbers. [ABSTRACT FROM AUTHOR]

This paper investigates the robust time‐varying formation control problems for a class of higher‐order multi‐agent systems subject to communication delays and heterogeneous uncertainties accounting for not only the parameter perturbations, nonlinearities and external disturbances occurring in the node local dynamics but also the nonlinear couplings in the interconnections of different nodes. For both cases of partially known and unknown time‐varying communication delays, we propose a unified formation control protocol, which incorporates a nominal controller to achieve the desired formation and a compensating signal to restrain the influences of uncertainties. Based on the signal compensation theory and Lyapunov–Krasovskii arguments, sufficient conditions to achieve the desired time‐varying formation are derived in terms of LMI. Thereafter, an explicit expression to describe the formation reference dynamics is yielded. Moreover, an algorithm is concluded to design the presented formation protocol in four steps. It is proven that the formation error can be made as small as desired under the designed controller despite the uncertainties and communication delays. Numerical simulation results are shown to demonstrate the effectiveness of our proposed control schemes. [ABSTRACT FROM AUTHOR]

This paper investigates the flocking control issue of multi-agent systems, where each agent utilizes the broadcasting communication manner and takes the Cucker–Smale style dynamic model. In the setting of broadcasting scenario, each agent broadcasts the state information only at certain moments determined by its own clock, and recalculates the control input only when its clock ticks or it receives information from the neighbors. In the Cucker–Smale model, a nonlinear weight function about the communication distance is set to portray the mutual influence degree between agents. With the help of the properties of sub-stochastic matrix, a comprehensive analysis of the asymptotic convergence of the model is performed and the algebraic conditions for achieving flocking control are established. In addition, the obtained theoretical results are further extended to the bipartite flocking control issue for multi-agent systems with both cooperative and competitive interactions. At last, numerical simulations are provided to verify the theoretical results. [ABSTRACT FROM AUTHOR]

In this paper, we focus on the consensus problem of leaderless multi-agent systems with external disturbance under denial-of-service (DoS) attacks. First, the state predictor is constructed to reproduce the state information blocked during the active periods of DoS attacks. Then, a robust non-smooth consensus protocol is designed using the predictor states, which mitigates the open-loop phenomenon caused by the DoS attacks. Besides, we obtain the sufficient condition for agents to achieve consensus within a region, and demonstrate that the protocol can enhance the anti-disturbance and anti-attack capabilities of the systems. Finally, the theoretical results are verified through numerical simulations. • We introduce a non-smooth consensus protocol based on predictive data to enhance the resilience of multi-agent systems against attacks. The incorporation of distributed predictors prevents the system from entering an open-loop mode due to data unavailability during active periods of DoS attacks. This ensures the avoidance of severe uncontrolled divergence behaviors of multi-agent systems during active periods of attack, thus ensuring rapid consensus recovery as the dormant periods of DoS attack start. • As observed in the current research on multi-agent system control under DoS attacks, linear or sliding mode consensus algorithms are commonly employed. In this study, by incorporating non-smooth functions, the multi-agent system is endowed with faster convergence speed and stronger disturbance resistance capacity. • We incorporate the multiple inertially stabilized platforms system. The effectiveness and superiority of the proposed consensus protocol are demonstrated through comparison with traditional consensus protocols. This not only offers empirical substantiation for future investigations but also emphasizes the practical applicability of studying the consensus of first-order multi-agent systems with external disturbance under DoS attacks. [ABSTRACT FROM AUTHOR]

This paper studies a class of distributed online convex optimization problems for heterogeneous linear multi-agent systems. Agents in a network, knowing only their own outputs, need to minimize the time-varying costs through neighboring interaction subject to time-varying coupled inequality constraints. Based on the saddle-point technique, we design a continuous-time distributed controller which is shown to achieve constant regret bound and sublinear fit bound, matching those of the standard centralized online method. We further extend the control law to the event-triggered communication mechanism and show that the constant regret bound and sublinear fit bound are still achieved while reducing the communication frequency. Additionally, we study the situation of communication noise, i.e., the agent's measurement of the relative states of its neighbors is disturbed by a noise. It is shown that, if the noise is not excessive, the regret and fit bounds are unaffected, which indicates the controller's noise-tolerance capability to some extent. Finally, a numerical simulation is provided to support the theoretical conclusions. [ABSTRACT FROM AUTHOR]

This paper is concerned with the output-feedback consensus problem of linear multi-agent systems on undirected graphs. Our focus is on reducing sensing and communication burdens between agents. Based on relative output measurements, a dynamic output-feedback (DOF) protocol is proposed, which, by leveraging the structure of the closed-loop dynamics, integrates a hybrid time/event-triggered sampling mechanism such that only intermittent interaction between agents is needed. Consensus conditions are established by the Lyapunov method and numerical simulations are provided for illustrating the effectiveness of the protocol. Compared with the existing results, the proposed DOF protocol has the following merits: (1) they rely on relative output measurements but do not need absolute measurements about agents; (2) they only require agents to intermittently interact with neighbors and thus can greatly reduce sensing and communication burdens between agents; and (3) the designed event-triggering conditions do not need to perform extra reconstruction operations that are computationally demanding. [ABSTRACT FROM AUTHOR]

In this paper, a randomized parallel algorithm is proposed to solve the distributed optimal consensus problem of multi-agent systems. Involving both the transient response and the final consensus state, the problem is described as a constrained non-separable optimization problem. Inspired by the randomized Jacobi proximal alternating direction method of multipliers, the proposed algorithm makes it possible for only a fraction of agents to solve their private subproblems in parallel at each iteration, which greatly saves computational resources and enhances running efficiency. The convergence analysis of the algorithm gives fully distributed convergence conditions. A trade-off between the convergence speed and resource savings is then obtained, where the convergence rate is estimated to be at least O 1 t . Furthermore, the algorithm can be accelerated to enjoy a convergence rate of O 1 t 2 by adaptively adjusting the auxiliary parameters properly. Numerical simulations demonstrate the effectiveness of the theoretical results. [ABSTRACT FROM AUTHOR]