Junyan Yu

Leader-following formation control for second-order multi-agent systems with time-varying delays

This paper investigates a leader-following formation control problem for second-order multi-agent systems with nonuniform time-varying communication delays under directed topologies. We first propose a consensus protocol and give a sufficient condition for second-order consensus of the system. Then, under a framework of multiple leaders, the protocol is applied to the formation control, including time-invariant formation and time-varying formation as well as time-varying formation for trajectory tracking. It is shown that the agents will attain the desired formation under the protocol. Finally, several simulations are conducted to illustrate the effectiveness of our theoretical results.

Consensus of first-order multi-agent systems with intermittent interaction

This paper studies the consensus problem of multiple agents with continuous-time first-order dynamics, where each agent can only obtain its states relative to its neighbors at sampling instants. It is assumed that the sampling period is different from the period of zero-order hold. Some sufficient and necessary conditions for consensus, which reveal the relationship among the interaction topology, controller gains, and the periods of sampler and zero-order hold, are provided. Moreover, the convergence rate is compared with that in the case when the period of zero-order hold is the same as the sampling period. Simulations are performed to validate the theoretical results.

Design of multiple controllers for networked control systems with delays and packet losses

We address stabilization problems of networked control systems in the presence of bounded packet losses and time-varying network-induced delays. When the delay is less than the transmission interval, we prove that the stability of the closed-loop system is implied by that of a switched system. Based on theories on switched systems, we present stabilizing conditions by using packet-loss-dependent Lyapunov functions, and design multiple controllers depending on the packet loss and the network-induced delay. Furthermore, based on the stabilizing conditions, we discuss the robustness of the stabilization against the packet loss and the network-induced delay. Several numerical examples and simulations are worked out to demonstrate the effectiveness of the proposed design approach.

Group consensus for second-order discrete-time multi-agent systems with time-varying delays under switching topologies

This paper addresses group consensus for multi-agent systems with switching topologies and time-varying delays, where all agents are described by discrete-time second-order dynamics. Based on the relationship between zero/nonzero in-degree graphs and nonnegative matrices group consensus criteria, which is presented in terms of easily checkable graph topology conditions, is obtained for multi-agent systems with time-varying delays under switching topologies. Furthermore, numerical examples are presented to illustrate the obtained results, and the essential of some conditions and assumptions is verified for given switching communication topologies.

Formation Control of Second-Order Multiagent Systems with Time-Varying Delays

A formation control problem for second-order multiagent systems with time-varying delays is considered. First, a leader-following consensus protocol is proposed for theoretical preparation. With the help of Lyapunov-Krasovskii functional, a sufficient condition under this protocol is derived for stability of the multiagent systems. Then, the protocol is extended to the formation control based on a multiple leaders’ architecture. It is shown that the agents will attain the expected formation. Finally, some simulations are provided to demonstrate the effectiveness of our theoretical results.

Second-Order Leader-Following Consensus of Multiagent Systems with Time Delays

This paper is concerned with a leader-following consensus problem of second-order multiagent systems with a constant acceleration leader and time-varying delays. At first, a distributed control protocol for every agent to track the leader is proposed; then by utilizing the Lyapunov-Razumikhin function, the convergence analysis under both fixed and switching interconnection topologies is investigated. For the case of fixed topology, a sufficient and necessary condition is obtained, and for the case of switching topology, a sufficient condition is derived under some assumptions. Finally, simulation examples are provided to demonstrate the effectiveness of the theoretical results.

Consensus of Continuous-Time Multiagent Systems with General Linear Dynamics and Nonuniform Sampling

This paper studies the consensus problem of multiple agents with general linear continuous-time dynamics. It is assumed that the information transmission among agents is intermittent; namely, each agent can only obtain the information of other agents at some discrete times, where the discrete time intervals may not be equal. Some sufficient conditions for consensus in the cases of state feedback and static output feedback are established, and it is shown that if the controller gain and the upper bound of discrete time intervals satisfy certain linear matrix inequality, then consensus can be reached. Simulations are performed to validate the theoretical results.

Couple-group consensus for second-order multi-agent systems with the effect of second-order neighbours’ information

This paper investigates a couple-group consensus problem of second-order multi-agent systems with the impact of second-order neighbours’ information. For systems with/without time delays, couple-group consensus criteria are established in the form of linear matrix inequalities by utilizing both model transformation and stability theories. The main results indicate that the group consensus for multi-agent systems under the effect of second-order neighbours’ information can be achieved based on the premise of a generalized balanced couple. Finally, illustrative examples are presented to demonstrate the effectiveness of the theoretical results.

Group Consensus with a Dynamic Leader for Multiagent Systems via Sampled-Data Control

This paper considers a group consensus problem with a dynamic leader for multiagent systems in a sampled-data setting. With the leader’s state available to only a fraction of the followers, a distributed linear protocol based on sampled-data control is proposed for group consensus under fixed directed topology. On basis of -matrix theory, we derive a sufficient condition on the sampling period and the control parameter for ultimate boundedness of the tracking errors. Furthermore, simulation examples are provided to demonstrate the effectiveness of the theoretical results.