Multi-agent system

About: Multi-agent system is a research topic. Over the lifetime, 27978 publications have been published within this topic receiving 465191 citations. The topic is also known as: multi-agent systems & multiagent system.

High-Performance Consensus Control in Networked Systems With Limited Bandwidth Communication and Time-Varying Directed Topologies

Abstract: Communication data rates and energy constraints are two important factors that have to be considered in the coordination control of multiagent networks. Although some encoder–decoder-based consensus protocols are available, there still exists a fundamental theoretical problem: how can we further reduce the update rate of control input for each agent without the changing consensus performance? In this paper, we consider the problem of average consensus over directed and time-varying digital networks of discrete-time first-order multiagent systems with limited communication data transmission rates. Each agent has a real-valued state but can only exchange binary symbolic sequence with its neighbors due to bandwidth constraints. A class of novel event-triggered dynamic encoding and decoding algorithms is proposed, based on which a kind of consensus protocol is presented. Moreover, we develop a scheme to select the numbers of time-varying quantization levels for each connected communication channel in the time-varying directed topologies at each time step. The analytical relation among system and network parameters is characterized explicitly. It is shown that the asymptotic convergence rate is related to the scale of the network, the number of quantization levels, the system parameter, and the network structure. It is also found that under the designed event-triggered protocol, for a directed and time-varying digital network, which uniformly contains a spanning tree over a time interval, the average consensus can be achieved with an exponential convergence rate based on merely 1-b information exchange between each pair of adjacent agents at each time step.

Trust in Multiagent Systems

Abstract: Trust is a fundamental concern in large-scale open distributed systems. It lies at the core of all interactions between the entities that have to operate in such uncertain and constantly changing environments. Given this complexity, these components, and the ensuing system, are increasingly being conceptualised, designed, and built using agent-based techniques and, to this end, this paper examines the specific role of trust in multi-agent systems. In particular, we survey the state of the art and provide an account of the main directions along which research efforts are being focused. In so doing, we critically evaluate the relative strengths and weaknesses of the main models that have been proposed and show how, fundamentally, they all seek to minimise the uncertainty in interactions. Finally, we outline the areas that require further research in order to develop a comprehensive treatment of trust in complex computational settings.

Distributed $H_\infty$ Output-Feedback Control for Consensus of Heterogeneous Linear Multiagent Systems With Aperiodic Sampled-Data Communications

Abstract: This paper is concerned with the output-feedback controller design for consensus of a class of heterogeneous linear multiagent systems with the aperiodic sampled-data measurement. Under mild assumptions that the sampling periods are taken from a given set and the agent systems are time synchronized, an equivalent switched system model is first proposed for the heterogeneous agent system with nonuniform sampling. The overall leader-following tracking control problem (LFTCP) is then formulated as the output regulation of a discrete-time switched system. By using some algebraic manipulations, the control problem under consideration is further decoupled into two control subproblems, i.e., a static output-feedback (SOF) control problem plus a simple feedback control problem related to the communication topology. Based on the Lyapunov stability theory, some sufficient conditions are obtained for the solvability of LFTCP. In our results, the SOF controller gains are determined by solving some strict linear matrix inequalities. Finally, a simulation study on the modified Caltech multivehicle wireless testbed is presented to show the effectiveness of the proposed design method.

Developing Multiagent Systems with agentTool

Abstract: The advent of multiagent systems has brought together many disciplines and given us a new way to look at intelligent, distributed systems. However, traditional ways of thinking about and designing software do not fit the multiagent paradigm. This paper describes the Multiagent Systems Engineering (MaSE) methodology and agentTool, a tool to support MaSE. MaSE guides a designer from an initial system specification to implementation by guiding the designer through a set of inter-related graphically based system models. The underlying formal syntax and semantics of clearly and unambiguously ties them together as envisioned by MaSE.

Soft Control on Collective Behavior of a Group of Autonomous Agents By a Shill Agent

Abstract: This paper asks a new question: how can we control the collective behavior of self-organized multi-agent systems? We try to answer the question by proposing a new notion called ‘Soft Control’, which keeps the local rule of the existing agents in the system. We show the feasibility of soft control by a case study. Consider the simple but typical distributed multi-agent model proposed by Vicsek et al. for flocking of birds: each agent moves with the same speed but with different headings which are updated using a local rule based on the average of its own heading and the headings of its neighbors. Most studies of this model are about the self-organized collective behavior, such as synchronization of headings. We want to intervene in the collective behavior (headings) of the group by soft control. A specified method is to add a special agent, called a ‘Shill’, which can be controlled by us but is treated as an ordinary agent by other agents. We construct a control law for the shill so that it can synchronize the whole group to an objective heading. This control law is proved to be effective analytically and numerically. Note that soft control} is different from the approach of distributed control}. It is a natural way to intervene in the distributed systems. It may bring out many interesting issues and challenges on the control of complex systems.