Robust Stabilization of Uncertain Networked Control Systems with Data Packet Dropouts

The data packet dropouts phenomenon is usually inevitable when information transmit- ted among communication networks.In this paper,the robust stabilization problem for uncertain networked control systems with data packet dropouts is studied.First,an uncertain discrete-time switching system model is presented to describe these networked control systems.The stability equiv- alence is then proved between this switching system and an uncertain impulsive difference system. Moreover,a sufficient condition is obtained for the asymptotical stability of the nonlinear impulsive difference system.From this condition the robust stabilization problem is dealt with for the uncertain impulsive system.Main results are given in linear matrix inequalities.Finally a numerical example is given to illustrate the theoretical results.     

Robust stabilization for a class of nonlinear networked control systems

The problem of robust stabilization for a class of uncertain networked control systems （NCSs） with nonlinearities satisfying a given sector condition is investigated in this paper. By introducing a new model of NCSs with parameter uncertainty, network-induced delay, nonlinearity and data packet dropout in the transmission, a strict linear matrix inequality （LMI） criterion is proposed for robust stabilization of the uncertain nonlinear NCSs based on the Lyapunov stability theory. The maximum allowable transfer interval （MATI） can be derived by solving the feasibility problem of the corresponding LMI. Some numerical examples are provided to demonstrate the applicability of the proposed algorithm.     

Controller design for networked control system with data packet dropout and transmission delays

In this paper, the stabilization problem for a class of networked control systems （NCSs） with data packet dropouts and transmission time delays is considered, where the delays are time-varying and uncertain, the data packet dropout is modeled as a two-state Markov chain. To compensate the lost packet, a data packet dropout compensator is established. Thus a more realistic model for such NCSs is presented. Sufficient conditions for the stabilization of the new resulting system are derived in the form of linear matrix inequalities （LMIs）. Numerical example illustrates the solvability and effectiveness of the results.     

具有干扰输入的不确定奇异系统的有限时间控制器设计

The concept of finite-time stability for linear singular system isinduced in this paper. Finite-time control problem is considered for linear singular systems with time-varying parametricuncertainties and exogenous disturbances. The disturbance satisfies a dynamical system with parametric uncertainties. Asufficient condition is presented for robust finite-ime stabilization via state feedback. The condition is translated to a feasibility problem involving restricted linear matrix inequalities (LMIs). A detailed solving method is proposed for the restricted linear matrix inequalities. Finally, an example is given to show the validity of the results.     

Adaptive robust simultaneous stabilization of multiple n-degree-of-freedom robot systems

In this paper, the adaptive robust simultaneous stabilization problem of uncertain multiple n-degree-of-freedom (n-DOF) robot systems is studied using the Hamiltonian function method, and the corresponding adaptive L2 controller is designed. First, we investigate the adaptive simultaneous stabilization problem of uncertain multiple n-DOF robot systems without external disturbance. Namely, the single uncertain n-DOF robot system is transformed into an equivalent Hamiltonian form using the unified partial derivative operator (UP-DO) and potential energy shaping method, and then a high dimensional Hamiltonian system for multiple uncertain robot systems is obtained by applying augmented dimension technology, and a single output feedback controller is designed to ensure the simultaneous stabilization for the higher dimensional Hamiltonian system. On this basis, we further study the adaptive robust simultaneous stabilization control problem for the uncertain multiple n-DOF robot systems with external disturbances, and design an adaptive robust simultaneous stabilization controller. Finally, the simulation results show that the adaptive robust simultaneous stabilization controller designed in this paper is very effective in stabilizing multi-robot systems at the same time.     

Robust H∞ Networked Control for Uncertain Fuzzy Systems with Time-delay

A robust H∞ networked control method for Takagi-Sugeno （T-S） fuzzy systems with uncertainty and time delay is presented. A state feedback controller is designed via the networked control system （NCS） theory. Sufficient condition for robust stability with H∞ performance is obtained. Network-induced delay in network transmission and packet dropout are analyzed. Simulation result shows the validity of this control scheme.     

不确定时滞模糊系统的鲁棒H∞网络控制

A robust H_∞networked control method for Takagi-Sugeno (T-S) fuzzy systems with uncertainty and time delay is presented.A state feedback controller is designed via the networked control system (NCS) theory.Sufficient condition for robust stability with H_∞performance is obtained.Network-induced delay in network transmission and packet dropout are analyzed. Simulation result shows the validity of this control scheme.     

An LMI approach to robust H-infinity control for uncertain singular time-delay systems

The problem of robust H-infinity control for a class of uncertain singular time-delay systems is studied in this paper. A new approach is proposed to describe the relationship between slow and fast subsystems of singular time- delay systems, based on which, a sufficient condition is presented for a singular time-delay system to be regular, impulse free and stable with an H-infinity performance. The robust H-infinity control problem is solved and an explicit expression of the desired state-feedback control law is also given. The obtained results are formulated in terms of strict linear matrix inequalities （LMIs） involving no decomposition of system matrices. A numerical example is given to show the effectiveness of the proposed method.     

采样系统鲁棒稳定性分析的新方法

The lifting technique is now the most popular tool for dealing with sampled-data control systems. However, for the robust stability problem the system norm is not preserved by the lifting as expected. And the result is generally conservative under the small gain condition. The reason for the norm difference by the lifting is that the state transition operator in the lifted system is zero in this case. A new approach to the robust stability analysis is proposed. It is to use an equivalent discrete-time uncertainty to replace the continuous-time uncertainty. Then the general discretized method can be used for the robust stability problem, and it is not conservative. Examples are given in the paper.     

Adaptive control for a class of nonlinear systems with time-varying delays in state and input

This paper is concerned with the adaptive stabilization problem of uncertain input delayed systems.A solution to this problem is given for a class of uncertain nonlinear systems with time-varying delays in both state and input.An adaptive asymptotically stabilizing controller,which can guarantee the stability of the closed-loop system and the convergence of the original system state,is designed by means of the Lyapunov-Krasovskii functional stability theory combined with linear matrix inequalities (LMIs) an...     

Improved synthesis method for network-based control

A less conservative stability analysis condition for closed-loop delayed linear systems subjected to uncertain, bounded, non-differentiable, additive time delays is presented. The obtained stability condition is applied to the problem of networked control system robust design in the presence of network-induced delays and data packet dropouts. Illustrative examples are provided to show the advantage and applicability of the developed results in this case.     

Impulsive controller design for singular networked control systems with packet dropouts

This paper considers the problem of impulsive time-delay control for singular networked impulsive control systems(SNICSs) and uncertain SNICSs both with network-induced delay and packet dropouts. The parameter uncertainty is assumed to be norm bounded. The problem to be addressed is the design of robust impulsive time-delay feedback controllers such that the exponential stability of the resulting closed-loop system is guaranteed for admissible uncertainties. By applying Lyapunov function theory and Halanay Lemma, impulsive time-delay controller is derived through solving LMIs. Numerical examples are provided to demonstrate the application of the proposed method.     

基于脉冲微分系统模型的有损网络控制系统研究

针对闭环网络控制系统,在考虑网络数据传输可能发生丢包的情况下,提出了一类切换系统模型,并在此基础上导出了一类脉冲微分系统模型.从数学上严格分析了该模型的合理性,并利用驻留时间的概念得到了此系统模型的稳定性条件,进一步研究了能够忍受一定程度的数据丢包的稳定化控制器设计问题.最后给出了一个具体示例.     

一类不确定网络控制系统的鲁棒容错控制

研究了含有数据包丢失的不确定网络控制系统的鲁棒容错控制问题. 在执行器连续增益故障下,考虑前向网络通道和后向网络通道中存在满足马尔可夫性质的数据包丢失情况,将含有结构不确定性的闭环故障网络控制系统建模为马尔可夫跳变线性系统.基于这个模型,利用Lyapunov稳定性理论和矩阵不等式技术,给出了闭环故障系统随机稳定的充分条件,同时采用锥补线性化方法,给出了控制器设计方法.最后数例仿真验证了该设计方法的有效性.     

具有丢包的非线性奇异系统的网络脉冲控制器设计

针对给定的一类非线性奇异系统,设计了基于数据丢包的网络脉冲控制器.首先建立了非线性奇异网络脉冲控制系统的数学模型;然后根据李亚普诺夫稳定性理论,分别考虑系统在连续状态和脉冲时刻的指数稳定性条件,给出了基于数据丢包的网络脉冲控制器的设计方法,使网络脉冲控制器能够保证具有数据丢包的非线性奇异系统实现指数稳定;最后,以洛伦兹混沌系统为例表明了控制器设计方法的正确性.     

Controller design for networked control system with data packet dropout and transmission delays

In this paper, the stabilization problem for a class of networked control systems (NCSs) with data packet dropouts and transmission time delays is considered, where the delays are time-varying and uncertain, the data packet dropout is modeled as a two-state Markov chain. To compensate the lost packet, a data packet dropout compensator is established. Thus a more realistic model for such NCSs is presented. Sufficient conditions for the stabilization of the new resulting system are derived in the form of linear matrix inequalities (LMIs). Numerical example illustrates the solvability and effectiveness of the results.     

具有随机丢包的网络控制系统的镇定

研究具有随机丢包的网络控制系统(NCS)的镇定问题.同时考虑传感器节点到控制器节点(S/C)和控制器节点到执行器节点(C/A)的随机丢包,并分别对这两种丢包现象建模.基于Lyapunov稳定性理论,得到闭环系统全局均方渐近稳定的充分条件.进一步利用线性矩阵不等式(LMI)方法,得到状态反馈控制律的增益矩阵.数值仿真算例验证了所得结果的有效性.