基于经典理论的协作跟踪与干扰抑制技术

研究了当存在确定性干扰时, 多智能体系统的协作跟踪控制问题. 系统中个体之间的通信拓扑由时不变的有向图网络构成, 而每个个体的动态特性均由单输入单输出的线性系统描述. 本文将多智能体的分布式协调控制问题理解成并归结为输出调节问题来解决, 并由此提出了一种基于个体间相对输出反馈机制以及经典极点配置理论的分布式协作控制律. “内模原理”的使用也因此显得尤其重要. 此外, 为了分析所提出的控制律的稳定性, 本文还引入了复根轨迹的概念, 这是对经典根轨迹技术的推广, 它在本文中的有效应用显示了其潜在的应用价值.     

基于自适应分布式滤波观测器的多智能体系统编队控制

本文考虑了全局指令系统输出信息受到信道扰动情况下线性多智能体系统的编队控制问题.首先,基于协作式输出调节理论框架对线性多智能体系统的编队控制问题进行数学建模.其次,针对受到信道扰动的全局指令系统输出信息,提出了一类基于受扰输出的自适应分布式滤波观测器,在降低网络信息交换量的同时消除扰动的影响.最后,设计了输出反馈确定等价控制律,解决了线性多智能体系统的分布式编队控制问题.给出了数值仿真结果检验控制性能.     

基于博弈模型的多智能体覆盖控制问题

多智能体覆盖控制问题是多智能体分布式协作控制的一个重要研究方向,对于要完成给定任务的多智能体系统而言,保持整体的连通性以便信息的共享非常重要。为解决多智能体连通覆盖问题,在非合作博弈的基本模型上,提出了一种完全分布式的控制算法,即每个智能体仅利用通信范围内其他智能体的信息来独立决策自己的行动,使得系统能在基本保持全局连通的同时,实现对周围环境的最大覆盖。在决策每一步的行动时,每个智能体都希望和通信范围内的其他智能体保持尽可能大的距离,但又不能完全孤立,可看作是一个多目标组合优化问题。仿真结果表明了算法的有效性。     

一种基于分布式强化学习的多智能体协调方法

多智能体系统研究的重点在于使功能独立的智能体通过协商、协调和协作,完成复杂的控制任务或解决复杂的问题。通过对分布式强化学习算法的研究和分析,提出了一种多智能体协调方法,协调级将复杂的系统任务进行分解,协调智能体利用中央强化学习进行子任务的分配,行为级中的任务智能体接受各自的子任务,利用独立强化学习分别选择有效的行为,协作完成系统任务。通过在Robot Soccer仿真比赛中的应用和实验,说明了基于分布式强化学习的多智能体协调方法的效果优于传统的强化学习。     

具有复杂动力学的多智能体系统分布式优化综述

多智能体系统分布式优化由于其高效性、灵活性和可靠性等特点吸引了大量学者的关注,在多机器人协同控制、无线传感器网络、能源系统等领域具有广泛的应用前景.分布式优化的基本目标是利用智能体的个体目标函数梯度、自身及其邻居状态信息设计分布式控制协议,驱动所有智能体的状态或输出到全局目标函数的最优解,系统动力学是影响智能体状态演化的重要因素.鉴于此,在回顾现有连续时间分布式优化算法的基础上,根据系统动力学分类,尽可能全面地评述具有复杂动力学的多智能体系统分布式优化问题的最新研究进展,并对未来发展方向进行展望.     

多智能体系统安全性问题及防御机制综述

多智能体系统作为分布式人工智能的重要分支,已成为解决大型、复杂、分布式及难预测问题的重要手段。在开放网络中,多智能体系统仍面临许多安全问题,潜在的安全威胁很可能影响其实际应用的稳定性、快速性和准确性。基于目前已知的多智能体系统通用模型,介绍了多智能体系统通信协议、访问控制和协调机制中潜在的安全问题,规范了多智能体系统安全性问题的研究体系,总结了系统设计过程中可行的防御技术和隐私保护技术,最后展望了多智能体系统安全研究的发展方向。     

分布式人工智能与多智能体系统研究

智能体理论是一个发展很快的前沿领域。为了解决复杂问题出现了分布式人工智能,多个智能体的协作正好符合分布式人工智能的要求,因此出现了多智能体系统。文中介绍了分布式人工智能的特点,并着重介绍了分布式人工智能的一种分类———多智能体系统。多智能体系统也是分布式人工智能的一种有效的解决方法,同时分布式人工智能又推动了多智能体的发展。     

考虑状态受限和一致性的微电网二次控制

为解决交流微电网下垂控制产生的偏差问题, 本文采用二次控制对分布式电源输出电压和频率进行调节. 将微电网看成分布式多智能体系统, 智能体间通过稀疏网络进行通信, 运用多智能体一致性协议, 本文提出一种基 于障碍Lyapunov函数和自适应模糊系统的二次电压和频率控制器. 采用障碍Lyapunov函数设计控制器, 不但能保 持系统的稳定性, 还可使输出的电压和频率限制在预设的范围内. 采用自适应模糊系统可对系统中的一些参变量的 变化进行估计, 提高了控制器的鲁棒性. 本文给出了严格的稳定性证明. 通过对负载变化, 以及拓扑结构改变等的 仿真测试, 验证了所提方案的有效性.     

多智能体系统体系结构及协调机制研究综述

多智能体系统体系结构及其协调机制是多智能体理论中的核心问题,目前在国际上已 经发展了许多方法．本文按照这些方法的研究流派,分别予以介绍、比较并对它们的优缺点 进行评述,最后简要介绍了我们的研究内容．     

多速率分布式预测控制及其在热连轧活套系统中的应用

多智能体协调控制系统更适合采用分布式控制方式,但是处理智能体之间的耦合影响是分布式控制的一个难点.本文针对串联结构下的多智能体系统,提出一类多速率分布式预测控制策略,异步更新多智能体的控制律,能够充分考虑智能体之间的耦合影响,提高系统的稳定性,并给出了系统稳定的充分条件.最后,将多速率分布式控制算法应用到热连轧活套系统,仿真验证了方法的有效性和可行性.     

Cooperative output regulation of heterogeneous multi-agent systems based on passivity

This paper investigates the problem of cooperative output regulation of heterogeneous linear multi-agent systems. A passive framework is presented for the stabilisation analysis of cooperative output regulation, which can overcome the difficulty caused by the fact that the global dynamics of heterogeneous multi-agent systems depends on the global communication structure. An adaptive distributed observer is proposed to estimate the state of the exosystem, and the proposed distributed observer is independent of any global information of the communication graph. Based on passivity design and adaptive distributed observer, both a distributed state feedback and a distributed output feedback protocol are designed for output synchronisation of heterogeneous multi-agent systems. The gain matrices of the distributed protocols and observers are obtained by a Riccati equation design approach. Furthermore, sufficient local conditions for solving the problem of cooperative output regulation of heterogeneous multi-agent systems are presented. Finally, numerical simulation results are given to illustrate the effectiveness of the proposed distributed control schemes.     

Distributed output regulation of leader–follower multi‐agent systems

In this paper, distributed leader–follower control algorithms are presented for linear multi‐agent systems based on output regulation theory and internal model principle. By treating a leader to be followed as an exosystem, the proposed framework can be used to generalize existing multi‐agent coordination solutions to allow the identical agents to track an active leader with different dynamics and unmeasurable variables. Moreover, the obtained results for multi‐agent coordination control are an extension of previous work on centralized and decentralized output regulation to a distributed control context. Necessary and sufficient conditions for the distributed output regulation problem are given. Finally, distributed output regulation of some classes of multi‐agent systems with switching interconnection topologies are discussed via both static and dynamic feedback. Copyright © 2011 John Wiley & Sons, Ltd.     

Coordination of heterogeneous nonlinear multi-agent systems with prescribed behaviours

In this paper, we consider a coordination problem for a class of heterogeneous nonlinear multi-agent systems with a prescribed input–output behaviour which was represented by another input-driven system. In contrast to most existing multi-agent coordination results with an autonomous (virtual) leader, this formulation takes possible control inputs of the leader into consideration. First, the coordination was achieved by utilising a group of distributed observers based on conventional assumptions of model matching problem. Then, a fully distributed adaptive extension was proposed without using the input of this input–output behaviour. An example was given to verify their effectiveness.     

Distributed output regulation for linear multi-agent systems with communication delays

In this paper, a distributed output regulation approach is presented for the cooperative control of linear multi-agent systems in the presence of communication delays. Both dynamic state and output feedback control laws are designed for achieving the property of output regulation. Sufficient conditions for the existence of these control laws are provided in terms of linear matrix inequalities. Simulation results are given to support the efficiency of the proposed distributed output regulation approach.     

Distributed formation output regulation of switching heterogeneous multi-agent systems

In this article, the distributed formation output regulation problem of linear heterogeneous multi-agent systems with uncertainty under switching topology is considered. It is a generalised framework for multi-agent coordination problems, which contains or concerns a variety of important multi-agent problems in a quite unified way. Its background includes active leader following formation for the agents to maintain desired relative distances and orientations to the leader with a predefined trajectory, and multi-agent formation with environmental inputs. With the help of canonical internal model we design a distributed dynamic output feedback to handle the distributed formation output regulation problem.     

Cooperative output regulation of multi-agent systems with switched leader dynamics

In this paper, the cooperative output regulation problem for heterogeneous multi-agent systems is addressed by considering a switched leader dynamics. The switched leader dynamics consists of multiple linear models and a switching rule governing the switches among them. A switched leader is capable of generating various sophisticated reference signals for more complicated multi-agent coordination tasks. A novel distributed hybrid impulsive switching control scheme is proposed to achieve cooperative output regulation. Distributed switching stability is established using the average dwell-time technique with multiple Lyapunov functions. Moreover, the associated distributed control synthesis conditions are formulated in terms of linear matrix inequalities plus linear matrix equations. As a result, both switching rules for the leader and distributed switching protocols for the followers can be jointly synthesised via efficient semi-definite programming. An example has been used to demonstrate the effectiveness of the proposed approach.     

Robust cooperative output regulation under exosystem detectability constraint

ABSTRACT

This paper revisits the robust cooperative output regulation problem for a class of linear uncertain multi-agent systems. In particular, it is assumed here that the agents in the system can only access incomplete measurements of the exosystem, and the local regulated error signals are not available to the agents to be used in control. Under these assumptions, the agents in the system cannot independently reconstruct the exosystem dynamics, or rely on their own local measurements to achieve the objectives of the output regulation problem. The solution to the regulation problem proposed in this paper is a distributed dynamic control law that reconstructs the exosystem states, given a mild collective detectability assumption. Furthermore, the proposed distributed control law incorporates an internal model of the exosystem to allow for uncertain dynamics of the multi-agent system. A numerical example is offered to illustrate the effectiveness of the proposed control solution.     

Distributed event-triggered output regulation of multi-agent systems

Motivated by the future use of embedded microprocessors with limited resources and limited computational resources, the distributed output regulation with event-driven strategies problem of linear multi-agent systems is considered in this paper. The main task is to design distributed feedback by employing event-triggered technique for multi-agent systems such that all agents can track an active leader, and/or distributed disturbance rejection. Both leader and disturbance are generated by some external system (exosystem). Both distributed static and dynamic feedback with event-triggered strategy are constructed here. Then, the input-to-state stability of the closed-loop multi-agent system is analysed. Finally, a numerical example is given to validate the proposed control.     

Cooperative global output regulation of heterogeneous second-order nonlinear uncertain multi-agent systems

In this paper, we study the cooperative global output regulation problem for a class of heterogeneous second order nonlinear uncertain multi-agent systems. We first introduce a type of distributed internal model that converts the cooperative global output regulation problem into the global robust stabilization problem of the so-called augmented multi-agent system. Then we further globally stabilize this augmented multi-agent system via a distributed state feedback control law, thus leading to the solution of the original problem. A special case of our result leads to the solution of the global leader-following consensus problem for the second order nonlinear multi-agent systems without satisfying the global Lipschitz condition.     

Distributed Robust Containment Control of Linear Heterogeneous Multi-Agent Systems: An Output Regulation Approach

In this paper, we consider the robust output containment problem of linear heterogeneous multi-agent systems under fixed directed networks. A distributed dynamic observer based on the leaders’ measurable output was designed to estimate a convex combination of the leaders’ states. First, for the case of followers with identical state dimensions, distributed dynamic state and output feedback control laws were designed based on the state-coupled item and the internal model compensator to drive the uncertain followers into the leaders’ convex hull within the output regulation framework. Subsequently, we extended theoretical results to the case where followers have nonidentical state dimensions. By establishing virtual errors between the dynamic observer and followers, a new distributed dynamic output feedback control law was constructed using only the states of the compensator to solve the robust output containment problem. Finally, two numerical simulations verified the effectiveness of the designed schemes.