具有定常输入的二阶多智能体系统的平均一致性滤波

本文考察了具有定常输入的二阶多智能体系统平均一致性滤波问题,提出了一种比例-积分一致性滤波算法。在定常输入和固定对称连通拓扑的前提下,根据Routh判据和Nyquist判据分别得到二阶多智能体系统在无时延和相同通信时延约束下渐近收敛一致的收敛条件,且多智能体系统最终一致性状态为定常输入的平均值。最后,通过由5个智能体组成的多智能体系统在连通拓扑结构下的数值仿真,验证了理论结果的正确性。     

一种基于切换拓扑和事件触发机制的一致性协议

研究了一种新的基于切换拓扑的事件触发一致性协议,该协议设计了两个事件触发器,包括智能体状态演化引发的收敛事件触发器和拓扑变化引发的拓扑事件触发器,并给出了与事件触发器有关的公共Lyapunov函数的稳定性分析和理论证明,还设计了一种基于约束集的网络连通算法,用于提高网络的连通性。仿真实验结果表明,新的协议能够使得系统收敛一致,有效降低智能体控制器的更新频率,减少系统能耗,提升网络的连通效果,能为事件触发控制的后续研究提供理论支撑。     

多智能体一致性预测控制算法及其仿真研究

离散多智能体系统的一致性问题是复杂动态大系统中重要问题,对收敛速度更是研究的重点.设计了一种适用于任意无向连通结构的多智能体一致性预测控制算法μ-MPC,提高智能体的一致性收敛速度并扩展了离散系统采样步长的取值范围,增强了系统的稳定性.在一定理论分析的基础上,通过大量的仿真实例和与经典模型的比较,研究了算法在固定拓扑和切换拓扑系统中的快速性和鲁棒性.特别对于全连通结构系统有一定的参考价值.     

带强连通分支的多智能体系统可控包含控制

研究有强连通子图拓扑结构的有向多智能体系统领导者选择及可控包含控制问题.根据网络拓扑结构,智能体被分为两类:单元智能体和一般智能体.首先设计强连通子图中个体组成的单元智能体的一致性协议实现各个单元的一致;后由单元智能体和一般智能体构成新的拓扑结构,结合复杂网络可控性理论与二分图最大匹配算法确定满足网络可控的最少领导者集合,并为所有智能个体设计相应的控制协议,驱使跟随者渐近收敛到多个领导者组成的动态凸包中,从而实现网络的可控包含控制.仿真结果验证了理论分析的正确性.     

基于梯度估计的多智能体系统有限时间分布式优化

现有多智能体系统分布式优化算法大多具有渐近收敛速度,且要求系统的网络拓扑图为无向图或有向平衡图,在实际应用中具有一定的保守性.本文研究了具有强连通拓扑的多智能体系统有限时间分布式优化问题.首先,基于非光滑分析和Lyapunov稳定性理论设计了一个有限时间分布式梯度估计器.然后,基于该梯度估计器提出了一种适用于强连通有向图的有限时间分布式优化算法,实现了多智能体系统中智能体的状态在有限时间内一致收敛到全局最优状态值.与现有的有限时间分布式优化算法相比,新提出的有限时间优化算法适用于具有强连通拓扑的多智能体系统,放宽了系统对网络拓扑结构的要求.此外,本文基于Nussbaum函数方法对上述优化算法进行了拓展解决了含有未知高频增益符号的多智能体系统分布式优化问题.最后,通过仿真实例对提出的分布式优化算法的有效性进行了验证.     

组合连通拓扑下基于事件触发的多智能体快速一致性算法

针对组合连通拓扑下多智能体系统控制过程中存在通信和计算资源损耗大以及系统收敛速度慢等问题,提出一种新的具有状态预测器的事件触发一致性控制协议,通过设计状态预测器使每个智能体都能对其邻居智能体的未来状态作出预测;同时,对于智能个体给出了基于状态信息的事件触发条件,当状态误差满足该条件才触发事件.在该控制策略下多智能体系统可在节约通信和计算资源的同时具有更快的收敛速度.利用Lyapunov稳定性理论和代数图论,证明了所提事件触发控制策略能够有效实现组合连通拓扑结构下的平均一致性,且不存在Zeno行为.仿真实例进一步验证了理论结果的有效性.     

具有多时变时滞的多智能体系统在切换拓扑下的平均一致性

研究带有多时变时滞的二阶多智能体系统在切换拓扑下的平均一致性问题. 利用模型变换的方法和 Lyapunov-Krasovskii 理论, 以线性矩阵不等式(LMIs) 的形式给出了多智能体系统达到平均一致性的充分条件, 其通 讯拓扑图为联合连通的. 仿真结果验证了理论分析的正确性.

     

一种多智能体系统抗毁性拓扑结构构建方法

拓扑结构抗毁性对多智能体系统分布式协同控制完成既定的目标任务具有重要意义.文中研究多智能体系统拓扑结构,提出基于权重的分簇方法,通过虚拟骨干网的分布式提取,完成层次型拓扑结构的构建.在基于簇的层次型结构的基础上,提出关节点判断与中继节点运动控制相结合的分布式方法,实现网络的双连通,并阐述该方法在网络化火控系统中的应用.实验表明文中提出的概念和方法能提高多智能体系统拓扑结构的灵活性和抗毁性,为网络化无人作战理论在实践中的应用打下良好基础.     

联合连通条件下的二阶多智能体系统有限时间一致性控制

针对时变动态拓扑下无leader的二阶多智能体系统有限时间一致性控制问题,本文给出有限时间一致性协议,并对所提出的一致性协议进行理论分析.基于图论、Lyapunov稳定性理论、同次性理论和积分不等式方法,证明了当通信拓扑为联合连通时,有限时间一致性协议可保证系统在有限时间达到一致.最后给出仿真结果,验证了理论的有效性.     

非线性网络有限时间分布式跟踪控制

针对具有本质非线性动态的多智能体网络,基于微分包含理论研究有限时间协调跟踪问题。假设非线性动态满足Lipschitz条件且只有部分智能体已知目标动态,设计分布式混杂控制协议,应用非光滑稳定性分析方法给出系统实现有限时间跟踪的充分条件。若无向切换拓扑保持连通或有向拓扑具有生成树且强连通部分满足细致平衡条件,则选取合适的控制增益参数均能实现有限时间跟踪。最后通过仿真实验表明了所提出方案的有效性和正确性。     

Semi‐global output consensus of a group of linear systems in the presence of external disturbances and actuator saturation: An output regulation approach

This paper studies the problem of semi‐global leader‐following output consensus of a multi‐agent system. The output of each follower agent in the system, described by a same general linear system subject to external disturbances and actuator saturation, is to track the output of the leader, described by a linear system, which also generates disturbances as the exosystem does in the classical output regulation problem. Conditions on the agent dynamics are identified, under which a low‐gain feedback‐based linear state‐control algorithm is constructed for each follower agent such that the output consensus is achieved when the communication topology among the agents is a digraph containing no loop, and the leader is reachable from any follower agent. We also extend the results to the non‐identical disturbance case. In this case, conditions based on both the agent dynamics and the communication topology are identified, under which a low‐gain feedback‐based linear state‐control algorithm is constructed for each follower agent such that the leader‐following output consensus is achieved when the communication topology among the follower agents is a strongly connected and detailed balanced digraph, and the leader is a neighbor of at least one follower. In addition, under some further conditions on the agent dynamics, the control algorithm is adapted so as to achieve semi‐global leader‐following output consensus for a jointly connected undirected graph and the leader reachable from at least one follower. Copyright © 2015 John Wiley & Sons, Ltd.     

Discrete‐time global leader‐following consensus of a group of general linear systems using bounded controls

This paper deals with the problem of global leader‐following consensus of a group of discrete‐time general linear systems with bounded controls. For each follower agent in the group, we construct both a bounded state feedback control law and a bounded output feedback control law. The feedback laws for each input of an agent use a multi‐hop relay protocol, in which the agent obtains the information of other agents through multi‐hop paths in the communication network. The number of hops each agent uses to obtain its information about other agents for an input is less than or equal to the sum of the number of real eigenvalues on the unit circle and the number of pairs of complex eigenvalues on the unit circle of the subsystem corresponding to the input, and the feedback gains are constructed from the adjacency matrix of the communication network. We show that these control laws achieve global leader‐following consensus when the communication topology among follower agents forms a strongly connected and detailed balanced directed graph and the leader is a neighbor of at least one follower agent. Copyright © 2017 John Wiley & Sons, Ltd.     

具有动态领导节点的多智能体系统一致性分析

具有领导节点的一致性问题是多智能体协调控制重要研究内容。目前其研究结论主要集中在系统通信拓扑关系固定不变这一前提下,对于系统通信拓扑关系为动态变化时具有领导节点的一致性问题尚未得到完全解决。对系统通信拓扑关系为有向、时变情况下的具有领导节点的多智能体系统一致性问题进行研究。分析并给出了在领导节点为常值和时变两种情况下多智能体系统达到一致的条件。并通过矩阵论和图论相关知识给出了详细证明。最后通过仿真实例验证了结论的正确性。     

Event‐triggered global leader‐following consensus of a group of neutrally stable linear systems subject to input saturation

This paper studies the global leader‐following consensus problem for a multiagent system using event‐triggered linear feedback control laws. The leader agent is described by a neutrally stable linear system and the follower agents are also described by a neutrally stable linear system but with saturating input. Both the state‐feedback case and the output‐feedback case are considered. In each case, an event‐triggered control law is constructed for each follower agent and an event‐triggering strategy is designed for updating these control laws. These event‐triggered control laws are shown to achieve global leader‐following consensus when the communication topology among the follower agents is strongly connected and detailed balanced and the leader is a neighbor of at least one follower agent. The Zeno behavior is excluded. The theoretical results are illustrated by simulation.     

Dynamic consensus of high-order multi-agent systems and its application in the motion control of multiple mobile robots

In this paper, the leader-following consensus problem for multi-agent linear dynamic systems is considered. All agents and leader have identical multi-input multi-output (MIMO) linear dynamics that can be of any order, and only the output information of each agent is delivered throughout the communication network. When the interaction topology is fixed, the leader-following consensus is attained by H∞ dynamic output feedback control, and the sufficient condition of robust controllers is equal to the solvability of linear matrix inequality (LMI). The whole analysis is based on spectral decomposition and an equivalent decoupled structure achieved, and the stability of the system is proved. Finally, we extended the theoretical results to the case that the interaction topology is switching. The simulation results for multiple mobile robots show the effectiveness of the devised methods.     

Leader‐following control for multiple inertial agents

This paper investigates distributed controller design problem for a leader‐follower network in the presence of communication delays. Two main contributions are made in this work. First, the second‐order controlled consensus scheme for the weakly connected communication graph topology is proposed. A necessary and sufficient condition is given under which the exponential consensus is achieved. Meanwhile, the relationship among the agents' inertias, the allowable delay bound, the communication topology, the consensus convergence rate, and the control gains is unveiled. Second, the robustness performances of the distributed control scheme with respect to the communication failures and delays are provided. It is shown that if the communication failure rate and the topology switching frequency, respectively, satisfy the given bounds, the exponential second‐order controlled consensus can be achieved under a bounded delay. Numerical examples are given to illustrate the theoretical results. Copyright © 2010 John Wiley & Sons, Ltd.     

Distributed dynamic consensus under quantized communication data

Distributed dynamic average consensus is investigated under quantized communication data. We use a uniform quantizer with constant quantization step‐size to deal with the saturation caused by the dynamic consensus error and propose a communication feedback‐based distributed consensus protocol suitable for directed time‐varying topologies to make the internal state of each agent's encoder consistent with the output of its neighbors' decoder. For the case where the communication topology is directed, balanced and periodically connected, it is shown that if the difference of the reference inputs satisfies some boundedness condition, then the designed quantized dynamic consensus protocol can ensure the states of all the agents achieve dynamic average consensus with arbitrarily small steady state error by properly choosing system parameters. The lower bound of the required quantization levels and the method to choose the system parameters are also presented. Copyright © 2014 John Wiley & Sons, Ltd.     

Semi‐global leader‐following consensus of multiple linear systems with position and rate limited actuators

This paper studies the semi‐global leader‐following consensus problem for a group of linear systems in the presence of both actuator position and rate saturation. Each follower agent in the group is described by a general linear system subject to simultaneous actuator position and rate saturation. For each follower agent, we construct both a linear state feedback control law and a linear output feedback control law by using low gain approach. We show that semi‐global leader‐following consensus can be achieved by using these control laws when the communication topology among follower agents is a connected undirected graph, and the leader is a neighbor of at least one follower. Simulation results illustrate the theoretical results. Copyright © 2014 John Wiley & Sons, Ltd.     

Reaching global leaderless consensus in directed networks via smooth and bounded control

This short communication revisits the leaderless consensus problem in directed networks. The network topology is described by a general directed graph which is only needed to contain at least a directed spanning tree, and is not necessarily strongly connected. A bounded and smooth control law using the hyperbolic tangent function is developed as the consensus protocol. Explicit stability analysis based on Lyapunov's second method and the concept of condensation graph is given. The proposed approach transforms the leaderless consensus problem into two subproblems: reaching leader-following consensus under a graph containing a directed spanning tree with the leader being the root node and reaching leaderless consensus under a strongly connected graph. Remarkably, a perturbed system is formulated as the bridge between these two subproblems which are solved by Lyapunov's second method. The global leaderless consensus is achieved based on the stability of the perturbed system. Finally, two numerical examples are presented to illustrate the effectiveness of the proposed approach.