切换信息拓扑和时变时滞下离散时间线性多智能体系统一致性的平均驻留时间条件

研究了有向切换信息拓扑和时变时滞下离散时间线性多智能体系统的一致性问题.首先,通过适当的线性变换把一致性问题转化为相应的时变时滞线性切换系统的渐近稳定问题; 然后,利用构建的李亚普诺夫函数和平均驻留时间模式,建立了一致性问题可解的基于线性矩阵不等式的时滞依赖充分条件,研究了如下两种情形: 1)所有信息拓扑都是可一致的,2) 部分信息拓扑是可一致的; 最后,数值实例验证了结果的正确性.     

基于部分稳定性方法的离散时间多智能体系统的一致性

研究有向信息拓扑下离散时间线性多智能体系统的一致性分析与设计问题.利用提出的线性变换,将一致性问题转换为相应线性系统的部分变元渐近稳定性问题.基于部分变元稳定性理论,得到有向信息拓扑下离散时间线性多智能体系统达到渐近一致的基于矩阵Schur稳定性的充要条件和状态一致函数的解析表达式.同时设计了反馈增益矩阵.最后数值实例验证了所得理论的有效性.     

时变时滞与切换有向通信拓扑协议下线性多智能体系统一致性的平均驻留时间条件

研究时变时滞与切换有向通信拓扑协议下高阶连续时间线性多智能体系统的一致性问题. 利用一个线性变换将该问题等价转化为一个切换时滞系统的稳定性问题. 假定出现的每一个通信拓扑都是可一致的, 借助时滞切换系统稳定性的平均驻留时间方法, 以线性矩阵不等式(LMIs) 形式给出多智能体系统达到全局一致的充分条件. 数值实例验证了结果的正确性.

     

离散时间高阶不确定线性多个体系统保性能一致性分析

本文研究了存在参数不确定性的离散时间高阶多个体系统保性能一致性问题,给出了一种设计其线性一致性协议的方法.首先,通过模型转换的方法将该问题转换为一组离散时间不确定系统的稳定性问题;然后,构造合适的Lyapunov函数并利用离散时间系统稳定性理论,推导出一个使离散时间高阶不确定多个体系统获得保性能一致的LMI充分条件;接着,以一致性序列的形式给出参数不确定条件下的离散时间高阶多个体系统的一致性收敛结果.最后,参数不确定的对比数值仿真验证了本文理论的正确性和有效性.     

具有时延和切换拓扑的高阶离散时间多智能体系统鲁棒保性能一致性

研究存在参数不确定性的高阶离散时间多智能体系统在时延和联合连通切换通信拓扑条件下的鲁棒保性能一致性问题,给出一种线性一致性协议的设计方法.1）引入高阶离散时间不确定多智能体系统的鲁棒保性能一致性问题,定义基于智能体邻居状态误差和控制输入的保性能函数;2）通过构造合适的Lyapunov函数并利用离散时间系统稳定性理论,推导出一个使高阶离散时间不确定多智能体系统在该条件下获得保性能一致性的线性矩阵不等式（Linear matrix inequality,LMI）充分条件,并给出相应的保性能上界;3）以一致性序列的形式给出参数不确定条件下的高阶离散时间多智能体系统的一致性收敛结果;4）数值仿真验证了本文理论的正确性和有效性.     

时变概率随机拓扑条件下高阶群系统一致性分析

在时变连接概率的随机拓扑条件下, 研究了离散时间高阶线性群系统的一致性问题. 首先, 给出一个依赖于相邻主体间拓扑连接概率和各个主体自身信息的随机控制协议; 然后, 应用状态空间分解法分析离散时间高阶线性群系统的一致性, 给出了在连接概率时变的随机拓扑条件下以概率为1 实现一致的充分必要条件; 进而, 确定了随机拓扑条件下离散时间高阶线性群系统的一致函数; 最后, 通过数值分析验证了所得出结论的正确性.

     

基于事件触发二阶多智能体系统的固定时间比例一致性

研究了在无向拓扑下, 由多个子群组成的二阶多智能体系统的固定时间比例一致性问题, 采用反推法设计了一种基于事件触发的固定时间非线性比例一致控制策略, 该策略包含分段式事件触发函数: 当智能体在追踪虚拟速度时, 给出了基于速度信息的触发条件; 当智能体速度与虚拟速度达到一致时, 切换至基于位置信息的触发条件, 可有效减少系统能量耗散及控制器更新频次. 通过在位置和速度状态上设置比例参数, 在固定时间内可实现不同子群智能体之间的比例一致. 利用代数图论、线性矩阵不等式以及Lyapunov稳定性理论, 证明在该控制策略下, 二阶多智能体系统能实现固定时间比例一致性, 且不存在Zeno行为. 最后, 仿真实例进一步验证了理论结果的有效性.     

具有通信时延的二阶多智能体系统有限时间一致性跟踪控制

针对具有通信时延的二阶多智能体系统的有限时间一致性控制问题,分别研究了具有固定拓扑和切换拓扑网络结构情形下的二阶多智能体系统的有限时间一致性。为使多智能体系统能在有限时间内可以达到一致,引入一致性控制增益矩阵并设计了相应的基于相对位置和相对速度的时延状态误差有限时间一致性控制算法,利用系统模型转换,泛函微分方程稳定性理论和有限时间Lyapunov稳定性定理得到了使系统在有限时间内达到一致跟踪的最大时延上界值。最后,仿真实验结果验证了所得理论的正确性和有效性。     

有限时间一致无迹Kalman滤波器

本文研究多个传感器测量非线性系统时的分布式无迹Kalman滤波器(Unscented Kalman filter, UKF)的设计问题.借助离散多智能体系统有限时间平均一致算法的思想, 针对无向通信和有向通信网络分别设计了两种不同的滤波算法.对于无向连通的通信拓扑, 利用节点存储的一致性算法的迭代值构造差向量, 由该差向量构成的Hankel矩阵的核来得到分布式无迹Kalman滤波器, 并通过利用误差协方差矩阵的逆来构造Lyapunov函数, 基于随机稳定性引理证明了该有限时间一致无迹Kalman滤波器的稳定性.对于有向强连通的通信拓扑, 结合比率一致和Hankal矩阵的核来设计分布式无迹Kalman滤波器, 该滤波器的稳定性与无向通信拓扑的滤波器相同.最后, 通过仿真例子来验证所提滤波器的跟踪效果.     

非线性随机多智能体系统的固定时间一致性

本文研究了在固定拓扑和切换拓扑下,非线性随机多智能体系统的固定时间一致性问题.首先针对固定拓扑,设计了一种非线性控制协议,利用随机Lyapunov稳定性理论和代数图论给出了实现固定时间一致性的充分条件和收敛时间的上界值,随后将结论推广至切换拓扑,设计的切换拓扑子图的并集只需要满足连通条件,即可实现固定时间一致,模型更具一般性.最后,两个仿真实例进一步验证了理论结果的有效性.     

切换信息拓扑和时变时滞下离散时间线性多智能体系统一致性的平均驻留时间条件（英文）

This paper investigates the consensus problem of discrete-time linear multi-agent systems(DLMASs) with directed switching information topologies and time-varying delays. First, we transform the consensus problem to an asymptotic stability problem of a corresponding time-delayed switched linear system(TDSLS) via a proper linear transformation. Then by using a constructed Lyapunov functional and the average dwell-time scheme, we establish a novel delay-dependent sufficient condition for the solvability of the consensus problem in terms of linear matrix inequalities(LMIs) for two cases, respectively: 1) all of the given information topologies are consensusable; 2) some of the given information topologies are consensusable. Finally, numerical examples are given to show the validness of the established results.     

Distributed consensus for multi-agent systems with delays and noises in transmission channels

This paper studies the distributed consensus problem for linear discrete-time multi-agent systems with delays and noises in transmission channels. Due to the presence of noises and delays, existing techniques such as the lifting technique and the stochastic Lyapunov theory are no longer applicable to the analysis of consensus. In this paper, a novel technique is introduced to overcome the difficulties induced by the delays and noises. A consensus protocol with decaying gains satisfying persistence condition is adopted. Necessary and sufficient conditions for strong consensus and mean square consensus are respectively given for non-leader–follower and leader–follower cases under a fixed topology. Under dynamically switching topologies and randomly switching topologies, sufficient conditions for strong consensus and mean square consensus are also obtained. Numerical examples are given to demonstrate the effectiveness of the proposed protocols.     

Stochastic consensus of single‐integrator multi‐agent systems under relative state‐dependent measurement noises and time delays

This paper proposes a consensus algorithm for continuous‐time single‐integrator multi‐agent systems with relative state‐dependent measurement noises and time delays in directed fixed and switching topologies. Each agent's control input relies on its own information state and its neighbors' information states, which are delayed and corrupted by measurement noises whose intensities are considered a function of the agents' relative states. The time delays are considered time‐varying and uniform. For directed fixed topologies, condition to ensure mean square linear χ‐consensus (average consensus, respectively) are derived for digraphs having spanning tree (balanced digraphs having spanning tree, respectively). For directed switching topologies, conditions on both time delays and dwell time have been given to extend the mean square linear χ‐consensus (average consensus, respectively) of fixed topologies to switching topologies. Copyright © 2016 John Wiley & Sons, Ltd.     

Necessary and sufficient conditions for mean square consensus under Markov switching topologies

This article deals with the mean square consensus problem for second-order discrete-time multi-agent systems. Both cases of systems with and without time delays in Markov switching topologies are considered. With the introduced control protocols, necessary and sufficient conditions for mean square consensus of second-order multi-agent systems are derived. Under the given control protocols in Markov switching topologies, the second-order multi-agent systems can reach mean square consensus if and only if each union of the graphs corresponding to all the nodes in closed sets has a spanning tree. Finally, a simulation example is provided to illustrate the effectiveness of our theoretical results.     

Consensus protocols for discrete-time multi-agent systems with time-varying delays

This paper addresses consensus problems for discrete-time multi-agent systems with time-varying delays and switching interaction topologies and provides a class of effective consensus protocols that are built on repeatedly using the same state information at two time-steps. We show that those protocols can solve consensus problems under milder conditions than the popular consensus algorithm proposed by Jadbabaie et al., specifically, the presented protocols allow for the case that agents can only use delayed information of themselves, whereas the popular one is invalid. It is proved that if the union of the interaction topologies across the time interval with some given length always has a spanning tree, then in the presence of bounded time-varying delays, those protocols solve consensus problems.