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This paper considers the sample-data-based consensus problem of multiagent systems with time-varying delay and packet losses. To distinguish the time delays caused by network-induced time-delay and packet losses, the switched system is utilized. A lower gain controller is designed based on the solution of a parametric algebraic Riccati equation. The Lyapunov stability theory is utilized to obtain the limitations on the frequency and the duration of packet losses which guarantees the consensus of multiagent systems. On the other hand, we theoretically prove that refined time-delay function can reduce the conservatism. A simulation example is given to illustrate the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

This paper investigates the robust containment control problem of multiagent systems with heterogeneous uncertainty and nonlinearity while the nonlinear parts have to satisfy the Lipschitz condition. In this paper, both input time-delay and data transmission time-delay between the agents are considered simultaneously and communication topology of the multiagent systems may switch in the steady-state condition. Under the mentioned conditions, the objective of this paper is to make all the followers’ states converge to the convex hull shaped by the leaders’ states with an expected exponential rate. To this end, an appropriate smooth protocol is proposed. Then, a Lyapunov–Krasovskii functional composed of five terms is proposed and the stability condition is denoted by two linear matrix inequalities (LMIs). In addition to the stability assurance, solving the LMIs would obtain the suitable gains for the protocol. Finally, some numerical simulations are given to verify the theoretical analysis. [ABSTRACT FROM AUTHOR]

This paper is concerned with the consensus problem of general linear dynamic multiagent systems with stochastic sampling. In this paper, the sampling intervals randomly switch between two different values. The communication topology between agents is fixed and directed. Full- and reduced-order observers are designed based on neighbor agents’ relative output information. The algorithms to construct such observers are also provided. By using the estimated states of the agents, the observer-based consensus protocol with stochastic sampling are presented. Sufficient conditions to ensure consensus in mean square are derived by using Lyapunov stability theory. Finally, simulations are given to examine the effectiveness of the proposed methods. [ABSTRACT FROM AUTHOR]

A specific class of nonlinear systems, admitting finite-duration attractors (FDAs), is introduced in this paper, and used for consensus of multiagent systems (MASs). The advantage is that one can obtain a closed-form solution for the settling time function of the presented nonlinear systems. Such a system exhibits a two-phase convergence process, and its settling time function takes values over a finite duration. However, the duration width changes with respect to the initial condition. The FDA-based consensus protocol is shown to make the MAS undertaken achieve finite-duration convergence. With illustrative examples, the perfect consensus property is verified for MASs with or without a leader agent. [ABSTRACT FROM AUTHOR]

The consensusability problems of general linear multiagent systems considering directed topologies are explored from a frequency domain perspective in this paper. By investigating the properties of Laplacian spectra, a consensus criterion is established based on the stability of several complex weighted closed-loop systems. Furthermore, for single-input multiagent systems, frequency domain consensusability criteria are proposed on the basis of the stability margins, which depend on the $ {\mathcal {H}}_{\infty }$ norm of the complementary sensitivity function determined by the agents’ unstable poles. The corresponding design procedure is also developed. A numerical example is also presented to validate the proposed consensusability results. [ABSTRACT FROM AUTHOR]

This paper addresses the distributed consensus controller design approaches for one-sided Lipschitz nonlinear multiagents by employing relative state feedback. A new treatment for one-sided Lipschitz nonlinearity is rendered from the consensus control point of view. By employing the quadratic inner-boundedness and the one-sided Lipschitz constraints, a sufficient condition for asymptotic consensus of nonlinear systems under strongly connected communication topologies is provided. Further, a robust consensus protocol design scheme for the nonlinear multiagents is derived by ensuring the ${L_{2}}$ stability of the consensus error system. Furthermore, a novel robust consensus control scheme against amplitude-bounded perturbations is developed that guarantees asymptotic convergence of the consensus error into a compact set. Extensions to the proposed methodologies for the leader-following consensus for a spanning tree communication topology with the leader as the root are addressed. In contrast to the conventional consensus control methodologies, this paper is less conservative and can be applied to a broader class of nonlinear multiagent systems. Moreover, the proposed consensus control approach is less conservative for robustness against disturbances owing to its ability to handle amplitude-bounded disturbances and due to the relaxation of a balanced communication topology. A numerical simulation study is provided for the consensus control of eight mobile agents. [ABSTRACT FROM AUTHOR]

This paper addresses the leaderless consensus control for a network of multiagent systems with the one-sided Lipschitz and quadratic inner-boundedness nonlinear dynamics. A distributed dynamic consensus protocol as a function of relative state feedback of the neighboring agents with edge-based adaptive coupling weights is designed for an undirected communication graph to achieve asymptotic consensus among the nonlinear agents. Further, an extension of the proposed consensus protocol in the presence of external disturbance is devised to ensure the ${L_{2}}$ stability of the consensus error. This paper is less conservative and more general owing to its application to the systems with large Lipschitz constants and to a broad class of the nonlinear systems. In comparison to the previous consensus control schemes, the proposed approach can be employed to design consensus protocols for the one-sided Lipschitz systems with unknown communication topology. This feature enables the fully distributed consensus control as the communication graph information is not required for the consensus protocol design. Simulation results for a network of six mobile agents are provided to demonstrate the effectiveness of proposed consensus schemes in the absence or presence of an external disturbance. [ABSTRACT FROM AUTHOR]

This paper surveys the literature over the last decades in the field of self-organizing multiagent systems. Self-organization has been extensively studied and applied in multiagent systems and other fields, e.g., sensor networks and grid systems. Self-organization mechanisms in other fields have been thoroughly surveyed. However, there has not been a survey of self-organization mechanisms developed for use in multiagent systems. In this paper, we provide a survey of existing literature on self-organization mechanisms in multiagent systems. We also highlight the future work on key research issues in multiagent systems. This paper can serve as a guide and a starting point for anyone who will conduct research on self-organization in multiagent systems. Also, this paper complements existing survey studies on self-organization in multiagent systems. [ABSTRACT FROM PUBLISHER]

This paper investigates the event-triggered consensus of linear multiagent systems with periodic data sampling mechanisms, where random packet losses are taken into account. The random packet losses occur in communication links based on a certain probability, and it is subject to the Bernoulli distribution. A novel distributed control protocol is designed based on the combined measurement to achieve the mean square consensus. By using the Riccati inequalities and linear matrix inequalities, an event-triggered condition with fewer parameters is also designed to reduce the information updating number. The interaction among the control gain matrix, sampling interval, and packet losses probability is used to describe the consensus conditions. The maximum sampling interval is presented explicitly. It is shown that the advantages of the proposed event-triggered strategy with the data sampling mechanism can avoid the Zeno behavior of the systems and continuous monitoring of the states. The simulations are provided to verify the proposed control strategy. [ABSTRACT FROM AUTHOR]

This paper is concerned with the fixed-time cooperative relay tracking control problem for a set of planar agents in a surveillance network. The plane is partitioned into multiple “capture regions” by using the Voronoi partition according to agents’ positions. Once an evader enters into a new capture region, one agent of the tracer team stops and the tracking mission is relayed to another one who is in charge of the new region. As a result, an impulsive model is proposed to describe the problem and a distributed fixed-time cooperative relay control strategy is provided that is not dependent on initial condition. Numerical simulations are provided to demonstrate the validness of the cooperative relay tracking scheme. [ABSTRACT FROM AUTHOR]

The work presented in this paper describes a multi-issue negotiation protocol between active consumers and a management platform in order to establish load coordination in a highly congested network. The multi-issue negotiation protocol considers simultaneously the consumption interval, the price, and the size of the energy packages, which is the main contribution of this work. Regarding the implementation methodology, the proposed algorithms have been implemented using MATLAB classes that allow emulating the behaviour of a multi-agent system in which each vehicle is an agent that interacts with the platform, which is another agent. In the present work, and without loss of generality, the algorithm is applied to coordinate the charging of electric vehicles (EVs) in a distribution network in which building loads represent critical loads. The algorithm is tested in a realistic environment, and its stability and performance are evaluated. Furthermore, the description of the algorithm is provided in a generic form, and it could be applied to any other scenario. [ABSTRACT FROM AUTHOR]

The state estimation problem of heterogeneous multi-agent systems with random transport protocol is investigated in this paper. Due to the dependency of the agent dynamics and the random sparse structure induced by the random transport protocol, the optimal state estimation design becomes complex and challenging. An optimal state estimator is successfully designed by the Hadamard product and gradient method. Based on the analysis of the matrix functions, a sufficient condition is established to guarantee that the average estimate error covariance is limited. Finally, a numerical example and a smart grid model are utilized to demonstrate the effectiveness of the deigned estimator. [ABSTRACT FROM AUTHOR]

In this paper, the leader-following consensus problem of multiagent systems with general dynamics under event-triggered mechanisms is investigated. A centralized event-triggered mechanism (CEM) is first proposed. Then, a distributed dynamic event-triggered mechanism is developed by introducing an internal variable. In the CEM case, each agent uses global information of the multiagent system, while in the distributed case, each agent only uses local information of its own and its neighbors. The multiagent system can achieve asymptotic consensus as well as exclude the Zeno phenomenon under the designed event-triggered rules in both cases. A multiagent system consisting of interconnected pendulums is provided to demonstrate the merits and correctness of the proposed methods. [ABSTRACT FROM AUTHOR]

This paper considers leader-following bipartite consensus of single-integrator multiagent systems in the presence of measurement noise. To attenuate the noise, a time-varying consensus gain ${q}$ (${t}$) is introduced into the stochastic approximation-type protocol. Necessary and sufficient conditions for ensuring a strong mean square leader-following bipartite consensus are given. In particular, in the absence of measurement noise, the convergence speed of error dynamics is dependent on the eigenvalues of Laplacian and the rate of ${\int ^{{t}}_{0}{q}({s})\text {d}{s}}$ approaching infinity. By appropriately choosing ${q}$ (${t}$), the speed of leader-following bipartite consensus convergence can be improved in a fixed communication topology. It is proven that conditions for the signed digraph to be structurally balanced and having a spanning tree are necessary and sufficient to ensure leader-following bipartite consensus, regardless of measurement noise. [ABSTRACT FROM AUTHOR]

This paper considers the consensus control problem of heterogeneous linear multiagent systems. A distributed proportional–integral (PI) protocol is presented to ensure consensus of heterogeneous linear multiagent systems with directed communication graphs. Sufficient conditions for the choice of control parameters are derived. For the case that the agents are subject to the external time-varying but bounded disturbances, the proposed distributed PI protocol can assure uniformly ultimate boundedness of the consensus error. The effectiveness of the results is illustrated both theoretically and numerically. [ABSTRACT FROM AUTHOR]

This paper focuses on the mean square practical leader–following consensus of second-order nonlinear multiagent systems with noises and unmodeled dynamics, where all agents are influenced by noises emerging from the input channels. We present a new distributed protocol, which contains a designed signal to dominate the effects of unmodeled dynamics, to solve the mean square leader–following consensus problem for the nonlinear multiagent systems. The protocol is designed without using any global information, even the eigenvalues of the Laplacian matrix. The Lipschitz constant of the nonlinear function is also unknown to all followers. Using the Lyapunov functional approach and the stochastic theory, it is proven that the mean square practical leader–following consensus is achieved by the designed protocol. Finally, two examples are provided to illustrate the effectiveness of the designed algorithm. [ABSTRACT FROM AUTHOR]

This paper is concerned with the fault-tolerant consensus control for a class of uncertain multiagent systems (MASs) via weighted edge dynamics. Different from the existing consensus results, the considered communication graph is weighted and the system model is assumed to be completely unknown. First, based on an important factorization of Laplacian matrix, a novel system named as weighted edge dynamics is introduced, and it is then proved that the stabilizing controller design for the transformed weighted edge dynamics is equivalent to the consensus controller design for the initial MAS. Within this framework, an efficient data-based algorithm is given to derive the fault-tolerant stabilizing controller, and the consensus of the initial MAS can be further ensured under the designed control protocol. Finally, some simulation examples on the LC oscillator networks are given to demonstrate the validity of theoretical results. [ABSTRACT FROM AUTHOR]

This paper proposes a global cooperative control framework to address leader-follower consensus of constraints subsystems of industrial plants, in which each subsystem is modeled as an agent and all the subsystems and networks of information flow construct a multiagent system. The focus of this paper is to solve the global leader-follower consensus for multiagent systems with input saturation via low-high gain feedback approach and parametric algebraic Riccati equation approach, in which the feedback gain design is distributed and decoupled from network topologies. By introducing appropriate assumptions, a class of low-high gain feedback protocol is designed based on the states of local neighbors to reach the global stability. It is proved in the sense of Lyapunov that, if the dwell time is larger than a positive threshold, the global leader-follower consensus for the closed-loop linear multiagent systems with input saturation under the derived topology containing a directed spanning tree can be achieved. The results are further extended to leader-follower consensus for nonlinear multiagent systems with the design of nonlinear low-high gain feedback protocol. As industrial applications of the proposed low-high gain scheduling approaches, the controller design of vibration in mechanical systems and satellite formation systems are revisited. Numerical simulations with cooperative control of industries subsystems show the effectiveness of the proposed approach. [ABSTRACT FROM AUTHOR]

This paper develops a fully distributed self-triggered framework for achieving the second-order consensus in multiagent systems. In this framework, a fully distributed self-triggered scheme is proposed to schedule information transmission for each communication channel. Thus, the communication frequency of each channel is significantly reduced. Here, communication over different channels is independent with each other and, thus, a channel-based control protocol is further proposed. The update times of control protocol could be also lowered in this framework. Here, an iterative evaluation method is constructed to design a fully distributed self-triggered scheme without involving any global information, especially the eigenvalue information of the Laplacian matrix. In addition, by introducing several variables, some sufficient conditions for achieving the second-order consensus and average consensus are obtained, respectively, in a distributed fashion, and the Zeno behavior is successfully eliminated. Finally, a simulation example is provided to verify the theoretical analysis. [ABSTRACT FROM AUTHOR]

This paper investigates the cooperative tracking control problem of multiagent systems where each agent is described as a Lur’e system. We first consider the case where the leader’s control input is zero and design a distributed adaptive event-triggered protocol for the followers to track the leader. We then deal with the general case where the leader contains a bounded control input by proposing a novel event-based protocol, including a nonlinear term to restrain the effect of the leader’s input. Both of the proposed event-triggered protocols can guarantee the uniform ultimate boundedness of the tracking error and the adaptive gains without the requirement of any global information of the network. The relationship between the upper bound of the tracking error and the controller parameters is explicitly derived. [ABSTRACT FROM AUTHOR]

This paper considers fixed-time consensus tracking of second-order multiagent systems (MASs) under directed interaction topology. A novel distributed observer is presented to estimate the leader’s states within a fixed time, which overcomes the difficulties caused by the asymmetry of the Laplacian matrix. A sliding surface is designed and a nonsingular terminal sliding mode consensus protocol is developed to achieve fixed-time convergence of the tracking error to the origin. It is shown that each follower can track the leader’s trajectory within a fixed time. Particularly, the gain of the presented consensus protocol is directly related to the prescribed time, which makes it convenient to determine and tune the gain according to the requirement of convergence time. Moreover, the presented control protocol reduces the conservativeness of the convergence time estimation for sliding motion. The simulation results validate the effectiveness of the proposed consensus scheme. [ABSTRACT FROM AUTHOR]

In this paper, the predefined-time consensus tracking problem of second-order multiagent systems (MASs) is investigated. A distributed observer is presented to estimate the tracking error for each follower within predefined time. A novel sliding surface is constructed to ensure predefined-time system convergence along the sliding surface and a terminal sliding mode consensus protocol is presented to overcome singularity problem and achieve leader-following consensus within predefined time. It is mathematically proved that the followers’ states can track the leader’s trajectory within predefined time. In particular, the settling time bound is directly related to tunable parameters, which facilitates the control protocol design to meet the desired convergence time requirement. Besides, the estimation bound for convergence time is less conservative than some existing fixed-time consensus protocols. The effectiveness of the proposed method is verified by the consensus tracking control for networked single-link robotic manipulators. [ABSTRACT FROM AUTHOR]

This paper studies the consensus in fractional-order multiagent systems over directed graph via sampled-data control method. A distributed control protocol using the sampled position and velocity data is designed. By virtue of the Mittag-Leffler function, Laplace transform, and matrix theory, some necessary and sufficient conditions associated with the sampling period, the fractional order, the coupling strengths, and the network structure to obtain consensus of the systems are obtained. Then, some detailed discussions are presented about how to select the sampling period and how to design the coupling strengths to attain the consensus of the systems, respectively. Lastly, some numerical simulation results are illustrated to reflect the availability of the theoretical analysis. [ABSTRACT FROM AUTHOR]

Within the multiagent systems framework, the relative states between neighbors can be acquired by some on-board sensors, and then the relative state saturations inevitably occur due to the limited sensing capabilities. This paper investigates the consensus problem of nonlinear multiagent systems subject to the relative state saturations. Utilizing the incidence matrix and the edge Laplacian, the consensus problem of nonlinear multiagent systems with the relative state saturations can be cast into the stabilization problem of edge dynamics operating on the constrained set. Three types of protocols, namely continuous, intermittent, and adaptive state feedback protocols are, respectively, proposed for achieving the constrained consensus, and meanwhile yielding consensus values. A consensus analysis is provided by virtue of state saturation theory, switched system theory, adaptive theory, and Lyapunov stability theory. Output feedback protocol is also designed. Finally, the obtained results are applied to connectivity preservation for first-order nonlinear multiagent systems, despite the presence of limited communication range and input constraints. The theoretical results are validated by two simulation examples. [ABSTRACT FROM AUTHOR]

This paper studies the event-triggered containment control (CC) problem of multiagent systems with a directed graph, where the followers’ communication graph is an undirected graph. A novel event-triggered CC protocol is presented to schedule communications between agents, which depends on both local states and control inputs. Different from traditional approaches using broadcasts, a unique property of the proposed protocol is that it enables agent-to-agent data transmission. To do so, each communication link is associated with a specific local event. The estimated relative interagent states are transmitted over a specific link only when the related input-based event is detected. We develop sufficient conditions to solve CC problem under this protocol and extend it to the adaptive event-triggered protocol that does not require the global knowledge on the smallest positive eigenvalue of the Laplacian. For both protocols, we derive positive low bounds on the interevent time intervals generated by individual events, which eliminate the “Zeno phenomenon.” Feasibility of the proposed algorithm is verified by an example. [ABSTRACT FROM AUTHOR]

To satisfy the increasing demands of cellular traffic, cooperative content caching at the network edge (e.g., User Equipment) has become a promising paradigm in the next-generation cellular networks. Device-to-Device (D2D) communications can improve the content caching and fetching performance without deploying additional infrastructure. In this paper, we investigate the joint optimization of cooperative caching and fetching in dynamic D2D environment for minimizing the overall content fetching delay. We formulate it as a decentralized partially observable Markov game for finding the optimal policies at agents. To address this problem, we propose a Fully Decentralized Soft Multi-Agent Reinforcement Learning (FDS-MARL) algorithm, which extends the soft actor-critic framework to non-stationary multi-agent environment for fully decentralized learning and it contains the following major design components: Graph Attention Network based self-attention for cooperative inter-agent coordination, a consensus communication mechanism for effectively reducing the information loss and non-stationarity of the environment while keeping gradual global consensus, and an influence based transmission scheduling mechanism for effective credit assignment and also alleviation of potential transmission contentions among agents. Simulation results show that FDS-MARL can improve the content caching and fetching performance significantly compared with the representative work in the literature. [ABSTRACT FROM AUTHOR]

This paper investigates the leader–follower robust ${H_\infty }$ consensus of heterogeneous multiagent systems with denial of service attack, where different attack intensities are considered. A switched system model is introduced to model such an attack phenomenon. Then, sufficient conditions to guarantee the solvability of the robust output consensus problem are obtained, and the quantitative relationship between the consensus performance and attack parameter is established. It is shown that the consensus protocol design problem can be transformed into two static output feedback (SOF) control problems. It is also shown that the SOF controller gains can be determined by solving some linear matrix inequalities without the knowledge of the probability information of each attack. Finally, the effectiveness of the control protocol is demonstrated by a simulation study. [ABSTRACT FROM AUTHOR]

This paper addresses the consensus problem of linear multiagent systems via nonlinear couplings. First, we show that the multiagent system can achieve consensus via nonlinear couplings provided the coupling strength surpasses a threshold, which depends on the smallest nonzero eigenvalue of the interaction graph Laplacian. Second, an adaptive coupling protocol is proposed to adjust the coupling strength without any usage of global information. Some numerical simulations are given to illustrate the effectiveness of the proposed protocols. [ABSTRACT FROM AUTHOR]

This paper addresses the admissible consensus problem for homogenous descriptor multiagent systems with undirected graphs and disturbances. First, to achieve the consensus objective and attenuate the effects of disturbances, the distributed controllers are formulated and the admissible consensus problems are formulated. Another improvement emphasizes that the proposed approach can simplify the complexity of the admissible consensus analysis by using the state transformation during the admissible analysis and disturbances suppression analysis. Moreover, based on Riccati inequalities and linear matrix inequalities, two necessary and sufficient conditions are presented to ensure the admissible consensus and disturbances suppression objectives. Finally, two simulation examples are provided to demonstrate the effectiveness of the proposed approaches. [ABSTRACT FROM AUTHOR]

This paper is concerned with the consensus issue for a class of multiagent systems with Markovian switching topology under aperiodic sampled data measurements. By constructing a novel piecewise stochastic Lyapunov-Krasovskii functional, some novel conditions with less conservative are established such that the consensus is achieved in the mean square sense. In contrast to some previous publications, the sample period is no longer fixed and the transition probability matrix of Markovian switching topology is uncertain. This issue which is of practical and theoretical significance is further investigated when the sampled data controller of each agent is suffered from distinct time-varying input delay. Quite different with the related studies, a maximally allowable input delay upper bound is replaced by the permissible input delay interval. Furthermore, the corresponding consensus is elegantly obtained in terms of linear matrix inequalities. Finally, the effectiveness and practicability of our consensus criteria are well illustrated by the numerical examples. [ABSTRACT FROM AUTHOR]

In this paper, we study the consensus problem for high-order discrete-time multiagent systems with state, input, and communication delays, where the input and communication delays can be arbitrarily large yet exactly known. Moreover, the communication delays are different for different agents. Nested predictor-based state feedback protocols and full-order/reduced-order observer-based output feedback protocols are established to solve the problem. It is shown that both the input and communication delays can be compensated completely. Furthermore, linear matrix inequalities-based approaches are provided to design state feedback gains and observer gains. A numerical example is worked out to illustrate the effectiveness of the proposed approaches. [ABSTRACT FROM AUTHOR]

This paper investigates leaderless consensus and leader-following consensus of multiagent systems with Lipschitz nonlinearity and input delay. For such systems, the observer-based truncated prediction feedback protocols are designed via dropping the distributed term and remaining the exponential term of the solution of the system equation over the delay period. Using Lyapunov–Krasovskii functional approach, two sufficient criteria are, respectively, established for achieving leaderless and leader-following consensus. The observer and controller gains are then obtained by means of an iterative linear matrix inequality procedure. A numerical simulation verifies the effectiveness of the proposed control design approach. [ABSTRACT FROM AUTHOR]

This paper studies the finite-time time-varying formation tracking problems for high-order multiagent systems (MASs) under the influences of both mismatched disturbances and the leader’s unknown input. The outputs of the followers can not only realize the prespecified finite-time formation but also track the desired trajectory generated by the leader in finite time. First, a disturbance observer is designed for every follower to estimate the disturbances in finite time. Then, based on the homogeneous finite-time control, the integral sliding mode control, and the super-twisting algorithm, a distributed formation tracking protocol is presented utilizing the neighboring interaction. The proposed protocol is continuous, so the large chattering of the control inputs can be avoided effectively. Furthermore, it is proved that the desired formation tracking can be realized in finite time by MASs in the presence of mismatched disturbances and the leader’s unknown input. Finally, a simulation example is designed to verify the theoretical results. [ABSTRACT FROM AUTHOR]

This paper is devoted to the problem of distributed fault estimation for multiagent systems with nonlinear dynamic. For each agent, an augmented system can be obtained by treating the possible fault as a special system state. Utilizing the output of the neighbor agents, the nonlinear fault estimation observer can be constructed in one agent. The possible faults in both this agent and its neighbors can be estimated by the observer. By solving linear matrix inequalities, the parameter matrices of the observer can be computed. The region pole constraint is considered, which can improve the estimation performance. At last, both a numerical simulation and a network of four one-link flexible joint manipulator systems are considered to verify the proposed fault estimation approach. [ABSTRACT FROM AUTHOR]

This paper investigates the quantized consensus problem of general linear multiagent systems (MASs) by event-triggered control. A novel event-triggered distributed control protocol is proposed based on a new dynamic quantizer. Compared with periodical sampling for most existing works on quantized consensus, the proposed event-triggered control approach can significantly save communication and thus energy resource. It is shown that with the proposed distributed control protocol quantized consensus of the concerned MAS can be achieved, and the Zeno behavior and continuous monitoring of the neighbors’ states are avoided. Moreover, it is shown that the required number of the quantization levels of the new quantizer remains small even if the number of the agents in the MAS is large. Three simulation examples are given to illustrate the effectiveness of the proposed consensus protocol. [ABSTRACT FROM AUTHOR]

This paper is concerned with general coopetition networks with signed graphs, based on which both the bipartite consensus and tracking control problems for networked systems subject to nonidentical matching uncertainties are studied. For the case of undirected and connected communication graphs, we propose a distributed discontinuous nonlinear controller which can achieve the bipartite consensus. To cancel the chattering phenomenon of the discontinuous controller, a continuous one is designed by using the boundary layer technique, under which the bipartite consensus error is shown to be uniformly ultimately bounded and can exponentially converge to a small adjustable bounded set. Further, considering the case of a leader having a bounded control action, we present a continuous controller to guarantee the ultimate boundedness of the bipartite tracking error. [ABSTRACT FROM AUTHOR]

Within the framework of multiagent systems, relative information can be directly acquired by vehicle-mounted sensors and the relative information constraints inevitably occur due to limited sensing capabilities. This paper investigates observer-based consensus of nonlinear multiagent systems subject to relative state estimate constraints. Each agent’s state is constructed via a state observer, and the relative state estimate is assumed to be confined into a hypercube. In virtue of the edge Laplacian, the consensus problem of nonlinear multiagent systems under this constraint is converted into the stabilization problem of edge dynamics operating on the constrained set. Observer-based intermittent protocol and adaptive protocol are, respectively, designed for achieving consensus. A convergence analysis is provided with the help of state saturation theory, switched system theory and adaptive theory. Finally, the results on consensus with relate state estimate constraints are applied into the consensus problem while preserving the connectedness, and are validated by a simulation example. [ABSTRACT FROM AUTHOR]

This paper aims to address adaptive tracking control problem of distributed multiagent systems. Differing from some existing works, each follower under consideration is modeled by a nonlinear nonstrict feedback system, especially, the virtual and real control gains are unknown functions rather than constants. To overcome the difficulty caused by the unknown nonlinearities, radial basis function neural networks are employed to model those unknown nonlinearities. Then, adaptive neural approach and backstepping technique are combined to construct the consensus tracking control protocol. It is shown that under the action of the suggested control protocol, whole closed-loop system is stable and all the outputs of followers ultimately track the reference signal, i.e., the output of the leader, synchronously. Numerical simulation is presented to further demonstrate the efficacy of the suggested control proposal. [ABSTRACT FROM AUTHOR]

This paper studies the leader-following consensus problem for a class of strict-feedback multiagent systems with unknown nonlinearities and state time-delays under directed topology. By using the backstepping technique, an adaptive consensus control protocol is proposed, where neural networks are employed to neutralize uncertain nonlinearities. To eliminate the effects of time-delays, Lyapunov–Krasovskii functionals, and Young’s inequalities are used in the design process. It is notable that the computation burden is dramatically alleviated by proposing a novel adaptive mechanism. For communication topology containing a spanning tree, the proposed controller guarantees that the consensus tracking error will converge to an adjustable neighborhood of the origin. Finally, a numerical example is provided to validate the effectiveness of our result. [ABSTRACT FROM AUTHOR]

Aiming to solve the cluster lag consensus (CLC) problem of networked nonlinear agents with a switching topologies, this paper proposes a control algorithm based on the measurements of position and velocity. When the network has several clusters of agents, under the conditions that each cluster is a strongly connected digraph including isolated agents, and at least one agent in each cluster can communicate with the common leader each time, a sufficient condition is derived for reaching CLC. Finally, a numerical simulation is demonstrated to validate the proposed control algorithm and the developed conditions. [ABSTRACT FROM AUTHOR]