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1.
针对一类网络化控制系统,当考虑网络控制系统遭受PWM (Pulsewidth-Modulated)型DoS (Denial-of-Service, DoS)攻击时,提出一种基于缓存机制的记忆型事件触发机制策略.本文考虑的DoS攻击可检测,并且攻击的周期时长以及每周期内的最短休眠时间已知.为了减少网络控制系统中数据包的发送频次,本文设计了基于相对误差的新型事件触发策略,与传统事件触发策略相比,通过增加缓存器来有效利用已经发送的历史采样数据,最终达到改善系统动态过程的目的.接下来,综合考虑网络攻击和事件触发方案,建立了网络化切换系统模型,构造分段李雅普诺夫泛函,推导出系统指数稳定的结论并且对控制器增益及事件触发参数进行协同设计.最后,通过仿真案例,验证了所提出方法的有效性.  相似文献   

2.
针对具有周期拒绝服务(DoS)攻击的网络化系统,设计一种基于观测器的具有动态事件触发策略的控制器.首先,通过DoS攻击对网络化系统的影响建立了DoS攻击模型,采用切换系统的方法,将具有DoS攻击的网络化系统分为DoS攻击活跃子系统和DoS攻击休眠子系统.对不可测的系统状态设计状态观测器,通过在静态事件触发中引入一个内部...  相似文献   

3.
本文研究了DoS攻击下网络化控制系统记忆型事件触发预测补偿控制问题. 首先, 由于网络带宽资源有限和系统状态不完全可观测性, 引入了记忆型事件触发函数, 为观测器提供离散事件触发传输方案. 然后, 分析了网络传输通道上发生的DoS攻击. 结合上述记忆型事件触发方案, 在控制节点设计一类新颖的预测控制算法, 节省网络带宽资源并主动补偿DoS攻击. 同时, 建立了基于观测器的记忆型事件触发预测控制的闭环系统, 并且分析稳定性.通过线性矩阵不等式(LMI)和Lyapunov稳定性理论, 建立了控制器、观测器和记忆型事件触发矩阵的联合设计方案,并验证了该方案的可行性. 仿真结果表明, 该方案结合记忆型事件触发机制可以有效补偿DoS攻击, 节约网络带宽资源.  相似文献   

4.
针对具有时变时延的非线性网络化控制系统(NNCS),在离散事件触发的输出通讯机制下,研究了NNCS的保性能控制和H∞鲁棒控制问题。首先,设计NNCS动态输出反馈控制器以得到闭环系统,利用Lyapunov稳定性方法,给出闭环系统在无扰动情况下渐近稳定和保性能的充分条件;其次,在γ次扰动情况下完成系统的H∞鲁棒控制问题;然后,针对系统中出现的输出误差、时延、非线性项等因素的影响,采用变量替换法求解出NNCS动态输出反馈控制器;最后应用Matlab仿真验证所提方法的有效性。  相似文献   

5.
针对拒绝服务(DoS)攻击下的时变多自主体系统,在有限域内研究事件触发安全一致性问题。在信息传输过程中,拒绝服务攻击同时存在于测量和控制通道中。将拒绝服务攻击看作是驻留时间切换机制,增广系统转化为包含一个稳定子系统和一个不稳定子系统的离散驻留时间切换系统。为提高通信资源利用率,采用状态依赖阈值的事件触发机制来更新控制输入信号。基于多Lyapunov函数方法,以线性矩阵不等式形式给出系统一致指数稳定且具有期望H∞性能的两个充分条件以及可行的控制器增益。仿真实例验证了发生拒绝服务攻击时,多自主体系统仍然可以实现安全一致性。  相似文献   

6.
本文在Hi/H1优化框架下, 研究基于动态事件触发的无人机非线性系统故障检测问题. 高空、长航时无人 机需要通过通信网络与地面站进行数据交互, 以实现故障检测等复杂功能. 为了充分利用有限的通信资源, 采用动 态事件触发机制决定是否将测量输入输出数据传送给故障检测模块, 若传输数据不满足触发条件则被丢弃, 因此, 故障检测性能不仅受到干扰和故障影响, 还受到非事件触发时刻数据与实际系统数据误差影响, 即事件触发传输误 差影响. 为此, 针对无人机非线性系统, 提出一种新的动态事件触发Hi/H1故障检测方法. 该方法可以在动态事件触 发条件下, 实现故障检测滤波器残差与事件传输误差完全解耦, 能够避免连续通信和Zeno现象. 在Hi/H1优化框架 下, 通过Riccati方程递归计算, 得到动态事件触发故障检测滤波器的最优解. 最后, 以无人机非线性姿态控制系统为 例, 验证所提方法的有效性和可行性.  相似文献   

7.
本文研究受拒绝服务攻击下直流微电网的事件触发控制问题. 考虑到直流微电网的状态并不总是可获得, 设计了一个观测器来估计直流微电网的状态. 基于观测器的估计状态, 对于受拒绝服务攻击的直流微电网设计了一种新颖的弹性攻击的事件触发控制器. 所提出的控制器设计方法可以通过分离方法转化成一个凸问题. 此外, 在所设计的事件触发机制中, Zeno行为也被讨论并且通过矛盾法被排除. 最后, 一个实际的电网例子被用来验证所提出的控制方案的有效性.  相似文献   

8.
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。  相似文献   

9.
赵光同  曹亮  周琪  李鸿一 《自动化学报》2021,47(8):1932-1942
针对一类具有未建模动态及执行器故障的非严格反馈非线性互联大系统,提出一种基于事件触发机制的模糊分散自适应输出反馈控制算法.首先,通过设计模糊状态观测器估计系统中不可测的状态,并引入李雅普诺夫函数约束未建模动态.然后,提出一种基于事件触发机制的自适应容错控制器补偿多个执行器故障产生的影响.最后,利用障碍李雅普诺夫函数实现...  相似文献   

10.
网络攻击下信息物理融合电力系统的弹性事件触发控制   总被引:3,自引:0,他引:3  
本文将电动汽车(Electric vehicles,EVs)引入到典型的信息物理系统(Cyber-physical systems,CPS)智能电网中,采用负荷频率控制(Load frequency control,LFC)方法,能够快速抑制系统扰动所引发的频率变化.在考虑拒绝服务(Denial-of-Service,DoS)攻击的情况下,提出了一种弹性事件触发机制,使系统能够容忍攻击所造成的数据丢失.与此同时,PI型静态输出反馈控制器的输入按需更新,减少了通信负担.对于建立的闭环时滞系统模型,构造新型李亚普诺夫泛函,对系统进行稳定性分析,推导出系统所能承受的最大DoS攻击持续时间,并对控制器增益和弹性事件触发矩阵进行协同设计.最后,通过多域电力系统仿真,验证了所提出方法的有效性.  相似文献   

11.
For nonlinear networked control systems with deception attacks, the problem of dynamic event-triggered dissipative control is researched in this article. First, on the basis of nonlinear networked control systems model, a dynamic event triggered scheme is proposed to save impact of network bandwidth. Second, considering the impact of time delay, a networked time-delay system model under deception attacks is established. Third, by constructing a new and less conservative Lyapunov function, using linear matrix inequality and unilateral Lipschitz condition, we derive some new sufficient conditions to guarantee the asymptotically stability of nonlinear networked control systems and strictly ( 1 , 𝕊 1 , 1 )-dissipative performance. Besides, a cooperative design strategy of dynamic event triggered scheme parameters and controller gain is put forward. Finally, a simulation example is given to prove feasibility and rationality of the proposed strategy.  相似文献   

12.
This article is concerned with the problem of dynamic event-triggered prescribed performance control for nonlinear systems under signal temporal logic tasks. By utilizing the method of prescribed performance control, the constrained plant can be transformed into an unconstrained one, and a dynamic event-triggered feedback control law is generated for the transformed system to ensure that the signal temporal logic specification is satisfied. A dynamic event-triggered mechanism is designed to guarantee the event-triggered stability, safety and complex specification. Besides, Zeno phenomenon is definitely avoided. Compared with the continuous-time feedback controller, the event-triggered controller has proven to be effective in reducing sensing, communication and computation costs. Finally, two simulations are given to illustrate the effectiveness of theoretical results.  相似文献   

13.
介绍了移动IPv6协议的工作原理,分析总结了移动IPv6网络中三种主要的DoS攻击。针对NS-2环境提出了一套模拟移动IPv6中DoS攻击的具体实现方案。经过对仿真实验结果分析表明,DoS攻击对移动IPv6网络性能造成很大的影响。  相似文献   

14.
Denial of Service (DoS) attack poses a severe threat to the Internet. Entropy-based methods have been successfully used to detect specific types of malicious traffic. This paper presents a novel dynamic entropy-based model for the detection of DoS attack. Based on the theory of alive communication, the dynamic entropy model is constructed by combining the information entropy as well as the feature of netflow conversation correlation. This is the first application of the theory of alive communication in the network anomalies detection. To evaluate the performance of the dynamic entropy model, we compare it with the traditional information entropy model. The experiment results demonstrate the presence of traffic’s dynamic entropy and show that the dynamic entropy keeps stable under normal traffic. By contrast, it fluctuates significantly when the network subjects to DoS attacks. Moreover, the detection rate of dynamic entropy-based model is higher and can detect unknown DoS attacks effectively.  相似文献   

15.
This paper proposes a dynamic event-triggered mechanism based command filtered adaptive neural network (NN) tracking control scheme for strong interconnected stochastic nonlinear systems with time-varying output constraints. By designing a state observer, the unmeasured states of the systems can be estimated. The NNs are utilized to handle the unknown intermediate functions. In the controller design process, the asymmetric time-varying barrier Lyapunov functions are used to guarantee that the systems outputs do not violate the constraint regions. By integrating the command filter with variable separation technique, the controller design process is more simple, and the problem of algebraic-loop can be solved which caused by interconnected functions. According to the Lyapunov stability theory, it can be ensured that all signals of the systems are bounded in probability. Finally, the availability of the developed control scheme can be showed by the simulation example.  相似文献   

16.
In this article, the event-triggered (ET) output feedback control problem is discussed for a class of p $$ p $$-normal nonlinear time-delay systems. Different from the related existing literature, the linear growth condition is relaxed to the homogeneous one and the growth rate is unknown. In the case of unknown time-varying delays and control coefficients, nonsmooth control law and some extra redundant terms will be encountered in the design of ET controller, which would bring substantial challenges to the achievement of global convergence. To cope with unknown growth rate and time-varying delays, two dynamic gains and an appropriate Lyapunov–Krasovskii functional (LKF) are introduced. Then, a new dynamic ET mechanism is given, in which the triggering threshold can be tuned dynamically. It is proved that all the signals of the closed-loop system (CLS) are bounded. Corresponding examples are given to indicate the validity of the developed theoretical results.  相似文献   

17.
陈世明  邵赛 《控制理论与应用》2019,36(10):1606-1614
本文研究了在有向拓扑下,带有非线性动力学多智能体系统的固定时间一致性问题.提出了一种新的基于事件触发机制的非线性控制策略,对于每个智能体给出了基于状态信息的事件触发条件,当状态误差满足所给条件时才触发事件,能有效的减小系统的能量耗散和控制器的更新频次.利用Lyapunov稳定性理论和代数图论,证明在该控制策略下,多智能体系统在固定时间能实现领导跟随一致性,且不存在Zeno行为.相较于有限时间一致性策略,采用固定时间一致性策略系统的收敛时间不再依赖于系统的初始状态.最后,仿真实例验证了理论结果的有效性.  相似文献   

18.
In this paper, the bipartite consensus problem is studied for a class of uncertain high-order nonlinear multi-agent systems. A signed digraph is presented to describe the collaborative and competitive interactions among agents. For each agent with lower triangular structure, a time-varying gain compensator is first designed by relative output information of neighboring agents. Subsequently, a distributed controller with dynamic event-triggered mechanism is proposed to drive the bipartite consensus error to zero. It is worth noting that an internal dynamic variable is introduced in triggering function, which plays an essential role in excluding the Zeno behavior and reducing energy consumption. Furthermore, the dynamic event-triggered control protocol is developed for upper triangular multi-agent systems to realize the bipartite consensus without Zeno behavior. Finally, simulation examples are provided to illustrate the effectiveness of the presented results.  相似文献   

19.
本文提出了考虑输入饱和的一类不确定非线性离散系统的事件触发指令滤波控制方法. 采用指令滤波控制技术解决了传统反步法存在的“因果矛盾”问题, 引入补偿机制提高了系统的控制精度; 利用事件触发机制能够避免自适应律和控制律的频繁更新, 降低了计算负担, 提高了资源利用率; 运用模糊逻辑系统逼近系统中未知的非线性函数; 结合李雅普诺夫稳定性理论, 验证了提出的控制方案能够保证跟踪误差收敛到原点小的邻域内以及闭环系统的所有信号有界. 仿真结果表明, 本文提出的控制方法具有较强的鲁棒性及较好的跟踪性能.  相似文献   

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