考虑时变时滞的多移动智能体分布式编队控制

考虑到多移动智能体编队控制中的时变时滞问题,在所设计的编队框架下,基于一致性算法设计了具有不对称时变时滞的分布式编队控制律.该控制律仅使用全局速度导引信息和邻居状态反馈信息;在固定通信拓扑条件下,推导了具有时变时滞的闭环系统状态方程,应用改进的自由权矩阵方法获得了保守性更小的系统稳定条件,并在时变通信拓扑条件下,将拓扑变化处理为系统结构的不确定性,同样获得了时变通信拓扑下的系统稳定条件;进行了6个智能体在平面内编队运动的仿真,实例证明,理论结果是正确的.     

基于滑模的二阶多智能体快速抗扰一致性

针对带有外部未知扰动的二阶多智能体系统的领导—跟随有限时间一致性问题，本文设计出一种带有时变增益的有限时间干扰观测器，用以实现对每个跟随智能体中未知扰动的快速估计，在此基础上，本文结合超螺旋积分滑模控制方法并利用邻居智能体的位置和速度信息设计一种快速抗扰一致性协议，该协议能够保证存在非线性动态的多智能体系统有限时间一致性控制并能抑制抖振现象.同时，利用李亚普诺夫函数进行了稳定性的证明.最后，通过Matlab数值仿真进一步验证了所提出协议的可行性.     

离散异构多自主体系统时变编队-合围控制

针对高阶离散异构多自主体系统的时变编队-合围控制问题,考虑时变时延,提出分布式编队-合围控制协议.首先,在合理假设的基础上,通过模型转变和状态空间分解,将编队-合围控制问题转化为子系统的稳定性问题,再利用Lyapunov-Krasovskii函数,以LMIs的形式给出协议有效的充分条件,并指出LMIs的个数与系统中自主体的个数无关;然后,给出编队参考函数的具体形式,证明指出编队参考函数不受时变时延的影响;最后,通过固定和时变编队-合围仿真验证所设计的协议的有效性.     

基于事件触发的时变拓扑多智能体系统编队控制

针对资源受限的时变拓扑多智能体系统的编队控制问题,提出一种基于复合误差信息事件触发机制以减少不必要的信息传输,降低带宽占用,并设计了多智能体系统的编队控制协议和分布式事件触发机制.通过将多智能体系统的编队控制问题转化为闭环延时系统的稳定性问题,构造Lyapunov-Krasovskii函数并利用线性矩阵不等式技术,给出多智能体系统实现编队的充分条件.最后,通过仿真验证了所提出方法的有效性.     

多智能体系统编队控制相关问题研究综述

首先梳理了编队控制研究的脉络, 介绍了3 种经典的编队控制方法, 即跟随领航者法、基于行为法和虚拟结构法的研究思想; 接着综述了近年来发展的, 包容了上述3 种方法且基于图论的编队控制理论的研究成果, 包括多智能体系统图论的建模, 基于代数图论和基于刚性图论的多智能体编队控制律设计、编队构型变换等方面的研究成果; 然后从图论结果出发, 回顾了与编队控制密切相关的一致性、聚集/同向、群集/蜂拥和包络控制的最新进展; 最后, 为了促进多智能体系统在实际中的应用, 指出了多智能体编队控制研究中有待解决的若干问题.

     

多智能体系统初始状态一致性应用研究

针对一阶多智能体系统,研究了含有时滞和不含时滞两种情形下收敛到初始状态（认为初始状态都为0）的问题,提出了一种使多智能体系统能够收敛到初始状态的一致性协议。在此一致性协议的基础上,严格推导了该多智能体系统达到初始状态的充分性判据。结合无人机编队中的应用,给出了两种情况下多智能体系统收敛到初始状态的仿真,验证了所提出的一致性协议的正确性以及充分性判据的有效性。     

具有规定性能的多智能体动态事件触发编队控制

针对多智能体系统编队控制过程中面临的性能约束、输入饱和、通信资源受限等问题,研究一类具有规定性能的高阶非仿射多智能体系统编队控制问题,提出一种有限时间动态事件触发编队控制策略。首先利用反步法设计控制律,并引入微分跟踪技术解决“计算爆炸”问题,有效避免对复杂虚拟控制律的求导过程;其次采用模糊逻辑系统估计系统内部的不确定性,通过设计性能函数和饱和补偿系统使得多智能体满足规定瞬态性能并防止输入饱和所带来的影响;随后为了解决通信资源受限的问题,构造一个具有动态阈值的自适应事件触发协议,有效减少控制器与执行器之间的通信量;最后利用李雅普诺夫稳定性理论分析闭环系统的稳定性,保证编队误差将渐近收敛至0且系统中所有信号均有界。采用含有1个领导者和5个跟随者的多智能体模型进行仿真验证,结果表明,在该有限时间动态事件触发编队控制策略下,多智能体系统最终形成以领导者为圆心、跟随者都在圆上的编队队形,且编队误差在规定的范围内演化。     

基于一致性和自抗扰的多智能体编队控制方法

多智能体协同编队问题是多智能体研究的热点问题。本文主要研究了扰动环境下四旋翼无人机群的编队控制问题。首先对不含扰动的时变编队控制算法进行学习仿真；然后由于扰动因素风的存在,提出自抗扰控制技术来抑制扰动；最后将时变编队控制算法和自抗扰控制技术相结合,实现对扰动环境下无人机群的编队控制。通过仿真结果中的编队误差和编队轨迹验证了基于一致性和自抗扰的控制器有着更强的鲁棒性和抗干扰能力。     

有向切换拓扑下多智能体系统编队控制

针对多智能体系统编队形成过程中受lur'e型非线性项影响,并考虑降低系统通信要求,基于一致性理论,设计了分布式控制器,使得多智能体系统形成时变编队.利用Laplacian矩阵的特殊性质,对其进行分解,将多智能体系统的编队控制问题转化为低阶系统的稳定性问题.给出了切换拓扑的平均驻留时间概念,据此提供了一种设计分布式控制器...     

复杂无向网络连通性的一种高效判定算法

通信网络的拓扑结构连通性是多智能体系统一致性控制或编队控制等的理论前提.以往, 各种多智能体系统一致性控制或编队控制方面的文献仅侧重于控制协议、智能体动力学模型和控制律设计, 而缺乏对多智能体通信网络拓扑结构的连通性研究.网络连通性高效判定算法不仅是大规模多智能体系统一致性控制或编队控制的保证, 而且在图论、现代移动通信、计算机与交通等各种网络中有着重要和广泛的应用.针对复杂无向网络的连通性问题, 本文给出了一种新的高效判定算法、以及该算法的时间复杂度和空间复杂度的上界.该算法具有非常低的时间复杂度和空间复杂度, 且便于计算机实现, 因而具有重要的理论意义和广泛的实用价值.     

Consensus problem of heterogeneous multi-agent systems with time delay under fixed and switching topologies

Consensus problem is investigated for heterogeneous multi-agent systems composed of first-order agents and second-order agents in this paper. Leader-following consensus protocol is adopted to solve consensus problem of heterogeneous multi-agent systems with time-varying communication and input delays. By constructing Lyapunov-Krasovkii functional, sufficient consensus conditions in linear matrix inequality(LMI) form are obtained for the system under fixed interconnection topology. Moreover, consensus conditions are also obtained for the heterogeneous systems under switching topologies with time delays. Simulation examples are given to illustrate effectiveness of the results.     

Consensus with a reference state for fractional-order multi-agent systems

This paper investigates consensus of fractional-order multi-agent systems (MASs) with a reference state. First, a consensus control law with a constant reference state is given using graph theory and stability analysis of fractional-order. Then, a general control law and a particular one for consensus of fractional-order MASs with a time-varying reference state are proposed. Next, the above control laws are extended to solve formation tracking problem. Finally, several simulations are presented to verify the effectiveness of the obtained results.     

Global consensus for discrete-time multi-agent systems with input saturation constraints

In this paper, we consider the global consensus problem for discrete-time multi-agent systems with input saturation constraints under fixed undirected topologies. We first give necessary conditions for achieving global consensus via a distributed protocol based on relative state measurements of the agent itself and its neighboring agents. We then focus on two special cases, where the agent model is either neutrally stable or a double integrator. For the neutrally stable case, any linear protocol of a particular form, which solves the consensus problem for the case without input saturation constraints, also solves the global consensus problem for the case with input saturation constraints. For the double integrator case, we show that a subset of linear protocols, which solve the consensus problem for the case without saturation constraints, also solve the global consensus problem for the case with input saturation constraints. The results are illustrated by numerical simulations.     

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.     

Consensus of feedforward nonlinear systems with a time-varying communication delay

The consensus problem of feedforward nonlinear systems under an undirected network with a time-varying communication delay is studied. In order to solve this problem, new consensus controller with an additional design parameter that can eliminate the effect of a feedforward nonlinearity and a time-varying communication delay on the consensus problem is proposed. Also, it is proved that if an upper bound of time-varying delay is known, the proposed consensus controller can always solve the consensus problem of multi-agent systems even in the presence of feedforward nonlinearity and an arbitrarily large communication delay. A numerical example is given to illustrate the validness of the proposed approach.     

Distributed Time-Varying Formation Tracking Analysis and Design for Second-Order Multi-Agent Systems

Distributed time-varying formation tracking analysis and design problems for second-order multi-agent systems with one leader are studied respectively, where the states of followers form a predefined time-varying formation while tracking the state of the leader. Different from the previous results on formation tracking control, the formation for the followers can be described by specified time-varying vectors and the trajectory of the leader can also be time-varying. A distributed formation tracking protocol is constructed using only neighboring relative information. Necessary and sufficient conditions for second-order multi-agent systems with one leader to achieve time-varying formation tracking are proposed by utilizing the properties of the Laplacian matrix, where the formation tracking feasibility constraint is also given. An approach to design the formation tracking protocol is proposed by solving an algebraic Riccati equation. The presented results can be applied to deal with the target enclosing problems and consensus tracking problems for second-order multi-agent systems with one target/leader. An application in the target enclosing of multiple vehicles is provided to demonstrate the effectiveness of the theoretical results.     

异构变时延多智能体系统编队控制分析

实际工程应用中,异构多智能体的编队控制问题研究具有十分重要的意义。考虑现实环境影响,编队系统个体之间的通信变时延难以忽略。系统收敛速率是评价系统性能的重要依据,然而现有编队控制问题研究很少能给出相应的量化指标。针对上述情形,对包含一、二阶智能体的异构变时延系统的编队控制问题进行分析研究。首先,考虑固定有向通信拓扑情况,对领航跟随者模式下异构变时延多智能体系统提出线性一致性控制协议。然后,构建误差系统模型,利用图论与矩阵论分析方法,并结合Routh-Hurwitz定理与牛顿-莱布尼兹公式,获得系统实现编队控制的充要条件,同时得到估算系统收敛速率的不等式关系。最后,仿真算例中随机给定一种系统节点0全局可达的通信拓扑,并对不同时延情况的编队控制效果进行分析,验证一致性控制协议的正确性和有效性。     

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.     

Finite-time consensus of time-varying nonlinear multi-agent systems

This paper investigates the problem of leader–follower finite-time consensus for a class of time-varying nonlinear multi-agent systems. The dynamics of each agent is assumed to be represented by a strict feedback nonlinear system, where nonlinearities satisfy Lipschitz growth conditions with time-varying gains. The main design procedure is outlined as follows. First, it is shown that the leader–follower consensus problem is equivalent to a conventional control problem of multi-variable high-dimension systems. Second, by introducing a state transformation, the control problem is converted into the construction problem of two dynamic equations. Third, based on the Lyapunov stability theorem, the global finite-time stability of the closed-loop control system is proved, and the finite-time consensus of the concerned multi-agent systems is thus guaranteed. An example is given to verify the effectiveness of the proposed consensus protocol algorithm.