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This paper studies the expected-time tracking control problem for multiagent systems with disturbances and time delays. The expected-time control scheme can ensure that control objectives can be completed within the desired time. In the other words, the output signal can track the reference signal in an expected time. Based on a special error and the adaptive technology, the expected-time tracking consensus control scheme is achieved. Moreover, by using the neural networks technique, the unknown nonlinear functions which often exist in the dynamic of the system are handled. According to the Lyapunov stability theorem and the Lyapunov–Krasovskii function, it is proved that the consensus errors are semi-globally uniformly ultimately bounded. At last, the feasibility of the control method is verified by a simulation example. [ABSTRACT FROM AUTHOR]

This article focuses on the issue of scaled tracking consensus for discrete-time second-order multiagent systems under random packet dropouts, where the cases with a static leader and a dynamic leader are considered, respectively. The scaled tracking consensus means that all agents reach a consensus value determined by the leader but with different scales, and the phenomenon of packet dropout on each communication link is described as a Bernoulli variable independent of other communication links. By virtue of random environment-based scaled consensus algorithms, it is shown how to reconstruct the original system into augmented error systems with random coefficient matrices. With the kind assistance of substochastic matrix and super-stochastic matrix, sufficient conditions for the cases with a static leader and a dynamic leader are derived, respectively. Moreover, computer simulations are performed to demonstrate the dynamics of network agents under random packet dropouts. [ABSTRACT FROM AUTHOR]

Summary: This article studies the problem of consensus tracking control for second‐order agents in multiagent systems over switching signed digraphs. Compared with the existing consensus tracking works on the structurally balanced signed digraph where the antagonistic relations exist only between two independent subgroups, this article explores a more general case for the first time, in the sense that the antagonistic relation is allowed between any two agents. On the basis of the design of a cooperation‐antagonism environment‐based distributed algorithm, suitable model transformation vectors are utilized to convert the stability of original system into a product convergence problem of time‐varying superstochastic matrices. By analyzing the convergence, algebraic conditions between positive and negative weights are established to ensure that all followers can eventually reach the leader's state under switching signed digraphs with arbitrary antagonistic relations. Simulation examples are provided to demonstrate the effectiveness of our results. [ABSTRACT FROM AUTHOR]

Summary: This paper investigates the distributed scaled consensus problem of multiple agents with high‐order dynamics under the asynchronous setting, where each agent measures the neighbors' information at certain discrete time instants according to its own clock rather than the whole discrete process and all agents' clocks are independent of each other. Assume that the communication topology can be arbitrarily switched and the information transfer between agents has a time‐varying delay. Under the designed asynchronous distributed control protocol, it is shown that the agents with the same scale will reach a common final state, while the agents with different scales will reach different final states. Moreover, an effective parameters selection strategy is presented for a large number of gain parameters in high‐order multiagent systems based on novel model transformation techniques. Simulation examples are provided to demonstrate the high‐order scaled consensus performances for the agents in the presence of asynchronous setting. [ABSTRACT FROM AUTHOR]

Highlights • This paper studies the consensus problem of discrete-time heterogeneous multi-agent systems with random link failures and switching topologies. • The properties of the infinite products of time-varying random row-stochastic matrices and graph theory are explored to analyze this problem. • A sufficient condition that only depends on the topology structures is obtained. Abstract In this paper, we consider the issue of consensus among the agents with heterogeneous dynamics under random link failures that obey Bernoulli distribution. The heterogeneous multi-agent systems (MASs) are composed of hybrid dynamic agents including first-order dynamic agents and second-order dynamic agents, and the communication topologies are assumed to be directed and time-varying. The failure control protocol is designed by randomly utilizing the previous one- or two-step states information sent by the neighbors. A criterion for the heterogeneous consensus is established by constructing augmented systems with nonnegative random coefficient matrices for the switching topologies. With the help of graph theory and stochastic matrix theory, a sufficient condition related to switching topologies is established to ensure the realization of heterogeneous consensus. Numerical examples are finally provided to validate the theoretical result. [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]

Compared with the traditional cooperative networks, the signed networks containing both cooperative and competitive interactions have prevailed. In light of such consideration, the problem of bipartite containment control for second-order multiagent systems (MASs) including multiple leaders over signed networks is investigated in this paper, in which time-varying delays and switching topologies are considered. Firstly, an augmented system method is explored such that the bipartite containment problem is formulated as the convergence problem of the product of an infinite number of sub-stochastic matrices. Then, by constructing a new leader–follower topology for each switching topology, the corresponding relationships between two topologies are used to simplify our model. Moreover, based on the properties of non-negative matrix and the technique of edge composition, a mild topological condition is developed for guaranteeing the bipartite containment collective behavior. Finally, numerical examples are presented for verifying the correctness of our conclusion. [ABSTRACT FROM AUTHOR]

In this contribution, we aim to examine the scaled consensus problem for heterogeneous multi-agent systems, which comprise two kinds of agents: the agents with first-order dynamics and the agents with second-order dynamics. The scaled consensus here means that the ratios between the states of the agents asymptotically approach specified constants instead of the same value. Firstly, appropriate distributed control protocols are designed for first-order and second-order networked agents, respectively. Particularly, the effects of switching communication networks and time-varying delays on model performance are investigated in this paper. Secondly, an augmented system approach based on algebraic graph theory and non-negative matrix theory is adopted to solve the proposed scaled consensus problem. Finally, a sufficient criterion is established to certify the scaled consensus performance of mixed agents. The correctness of the theoretical result is demonstrated through several simulation examples. [ABSTRACT FROM AUTHOR]

Highlights • The containment control issue for discrete-time second-order multi-agents (MASs) with asynchronous intermittent communication is examined in this paper. • Hybrid tools including matrix theory and the composite binary relation are utilized to analyze this problem. • It is proved that although the followers can gradually enter into the convex hull of the leaders, and their positions after entering the convex hull may be time-varying. Abstract In this paper, a containment control issue for discrete-time second-order multi-agents (MASs) with asynchronous intermittent communication is analyzed, where each agent communicates with some of its neighbors at certain discrete time according to its own clock rather than the complete discrete process and all agents' clocks are independent of each other. By constructing the spanning subgraph of communication topology at each discrete time, the stability analysis of containment control under the asynchronous intermittent communication is equivalently transformed into the products convergence of nonnegative matrices. Hybrid tools including matrix theory and the composite binary relation are utilized to analyze this convergence issue. Unlike the existing results on the containment control with fixed topology, in which the followers will gradually enter into the convex hull constructed by the leaders and their final positions are fixed, it is theoretically proved in this paper that although the followers will enter into the convex hull of the leaders under the asynchronous intermittent communication, their positions after entering the convex hull may always be time-varying. Finally, the theoretical finding is verified by a simulation example. [ABSTRACT FROM AUTHOR]

Highlights • The asynchronous bipartite consensus for a group of agents with second-order dynamics is examined in this paper. • The properties of the product of infinite time-varying row-stochastic matrices from a noncompact set are explored to analyze this problem. • A sufficient condition that depends on switching topologies is established. Abstract The asynchronous bipartite consensus for a group of agents with second-order dynamics is examined in this paper, where the asynchrony means that the time instants when each agent receives the neighbors’ data information are completely independent of other agents’. The communication among the agents is described by a time-varying signed and structurally balanced digraph, which is equivalent to assuming that the agents can be divided into two groups without any common agents, in which the agents within the same group are cooperative and the agents between different groups are competitive. An asynchronous distributed control protocol is designed to implement the bipartite consensus. By using the product properties of row-stochastic matrices from a noncompact set, a sufficient condition can be established under a loose assumption that is the union of communication topologies related to any time intervals with given length has a spanning tree. Finally, a simulation instance is provided to verify the reachability of asynchronous bipartite consensus. [ABSTRACT FROM AUTHOR]