不确定离散时滞控制饱和系统L2增益分析设计

针对离散时间不确定含时滞和控制饱和系统的镇定和干扰抑制问题,提出了状态反馈和抗饱和动态输出反馈方法。该方法利用Lyapunov函数可获得时滞相关的线性矩阵不等式。线性矩阵不等式条件可保证不确定闭环系统的无干扰时鲁棒内稳定性和在某椭球内预先给定的有干扰时L2性能水平。通过把状态反馈增益视为一自由参数,利用所得到的优化问题给出了控制器设计的具体步骤,通过仿真算例证明该方法的有效性。     

Global Disturbance Rejection of Switched Nonlinear Systems with Switched Internal Model

This paper investigates the problem of global disturbance rejection for a class of switched nonlinear systems where the solvability of the disturbance rejection problem for subsystems is not assumed. The disturbances are assumed to be sinusoidal with completely unknown frequencies, phases and amplitudes. First, as an extension of the classic concept of internal model for non-switched systems, a switched internal model is proposed. Second, in order to solve the problem under study, an adaptive control method is established on the basis of the multiple Lyapunov functions method. Also, adaptive state-feedback controllers of subsystems are designed and incorporated with a switching law to asymptotically reject the unknown disturbances. Finally, an example is provided to demonstrate the effectiveness of the proposed design method.     

多输入多输出网络控制系统的绝对稳定性分析

考虑到网络诱导时延和网络通道的非线性反馈干扰,研究了多输入多输出网络控制系统的时滞依赖稳定性。基于各回路有界的状态反馈输入,建立闭环系统的Lurie时滞系统模型。应用Lyapunov稳定性理论和线性矩阵不等式工具,分析了各子系统在有扇形条件约束的绝对稳定性,同时得到网络控制系统全局稳定运行的最大允许时延界。最后,通过仿真例子,表明该方法是可行的。     

STATE-FEEDBACK ADAPTIVE STABILIZING CONTROL DESIGN FOR A CLASS OF HIGH-ORDER NONLINEAR SYSTEMS WITH UNKNOWN CONTROL COEFFICIENTS

In this paper, a new approach is successfully addressed to design the state-feedback adaptive stabilizing control law for a class of high-order nonlinear systems in triangular form and with unknown and nonidentical control coefficients, whose stabilizing control has been investigated recently under the knowledge that the lower bounds of the control coefficients are exactly known. In the present paper, without any knowledge of the lower bounds of the control coefficients, based on the adaptive technique and appropriately choosing design parameters, we give the recursive design procedure of the stabilizing control law by utilizing the approach of adding a power integrator together with tuning functions. The state-feedback adaptive control law designed not only preserves the equilibrium at the origin, but also guarantees the global asymptotic stability of the closed-loop states and the uniform boundedness of all the other closed-loop signals.     

H∞ control for stochastic systems with time-delay

The H∞-control problem of stochastic systems with time-delay is considered. The sufficient conditions are obtained, under which there are always state-feedback control and dynamic output-feedback control so that the resulting closed-loop system is internaly stable and L2 input-output stable in the sense of expectation. Furthermore, the explicit formulas of both kinds of controls are derived. An example is included to illustrate the correctness of theoretic results.     

Adaptive Tracking Control for Mobile Manipulators with Stochastic Disturbances

This paper investigates adaptive tracking control for mobile manipulators with stochastic disturbances and parametric uncertainties. Based on an appropriate reduced dynamic model and an adaptive law, a controller, which is provided by incorporating stochastic control theory with related adaptive technique, overcomes the problem of over-parametrization. It is shown that the designed state-feedback controllers can guarantee that the mean square of the tracking errors can be made arbitrarily small by choosing suitable design parameters. Simulation studies on the control of 2-DOF mobile manipulator shows the effectiveness of the proposed scheme.     

广义线性系统的鲁棒状态反馈特征结构配置

针对具有参数摄动广义线性系统的鲁棒状态反馈特征结构配置问题 ,提出了一种优化算法。该算法的设计目标是使闭环特征值和特征向量所满足的方程组关于参数摄动误差为最小。根据广义线性系统状态反馈特征结构配置结果 ,给出了优化指标的完全参数表示。该算法简单、有效 ,且可以给出鲁棒性较强的控制系统。数值例子表明了算法的有效性     

直线不稳定船舶航迹控制的稳定性研究

针对直线不稳定船舶的全局直线航迹控制,提出了一类航迹非线性状态反馈控制算法。采用Lya-punov直接法分析系统的稳定性,得到了保证闭环控制系统全局渐近稳定的充分条件,从而解决了直线不稳定船舶航迹闭环控制系统全局稳定性的判定问题。数值仿真和模拟试验结果验证了该充分条件的正确性。     

基于变采样周期方法的网络控制系统协同设计

提出了一种基于变采样周期的动态调度策略,通过实时调整控制系统的采样周期以适应网络中信息流的变化,改善网络中时延、丢包等问题.采用动态调度策略的NCS为一个变采样周期系统,考虑时延的影响,通过等效变换将时延和采样周期的不确定性转化为系统参数的不确定性,从而将NCS建模为一类具有参数不确定性的离散时间系统,并给出了系统D-稳定的控制器设计方法,实现NCS的控制与调度协同设计.最后通过数值仿真验证了所提出的方法的有效性.     

Stabilization of coupled pde-ode systems with spatially varying coefficient

The paper is concerned with the stabilization of a class of coupled PDE-ODE systems with spatially varying coefficient, via state-feedback or output-feedback. The system is more general than that of the related literature due to the presence of the spatially varying coefficient which makes the problem more difficult to solve. By infinite-dimensional backstepping method, both state-feedback and output-feedback stabilizing controllers are explicitly constructed, which guarantee that the closed-loop system is exponentially stable in the sense of certain norm. It is worthwhile pointing out that, in the case of output-feedback, by appropriately choosing the state observer gains, the severe restriction on the ODE sub-system in the existing results is completely removed. A simulation example is presented to illustrate the effectiveness of the proposed method.     

<Emphasis Type="Italic">H</Emphasis><Subscript>∞</Subscript> control for stochastic systems with Poisson jumps

This paper discusses the H _∞ control problem for a class of linear stochastic systems driven by both Brownian motion and Poisson jumps. The authors give the basic theory about stabilities for such systems, including internal stability and external stability, which enables to prove the bounded real lemma for the systems. By means of Riccati equations, infinite horizon linear stochastic state-feedback H _∞ control design is also extended to such systems.     

A Family of Reliable H_∞ State-Feedback Controllers for Nonlinear Systems with Strictly Redundant Actuators: the Full Information Case

1　 IntroductionInherited from state space linear H∞ control theory,a number of nonlinear H∞ solutionshave been presented in terms of various formulations.The nonlinear H∞ control problemcan be stated as follows:find a compensator,either state feedback ormore general outputfeedback such that( 1 ) the internal state of the closed-loop system is stable and( 2 ) the L2 -gain of the mapping from the exogenous input disturbance to the controlled output liketracking error or cost variables is mi…     

基于干扰估计的BTT导弹鲁棒方差姿态控制

针对存在非线性和不确定性的倾斜转弯(bank-to-turn, BTT)导弹姿态控制问题,提出基于干扰估计的鲁棒方差控制方法。将姿态运动中非线性项和不确定项作为总干扰,采用干扰观测器进行估计,并引入控制系统进行补偿。干扰观测器的观测误差作为BTT导弹姿态运动的干扰输入,为了保证控制系统具有良好的动态和稳态性能,采用鲁棒方差控制理论设计了线性反馈控制器,将闭环极点配置在特定圆盘区域,同时将状态变量的稳态方差保持在给定的范围内。仿真结果表明,所提出的鲁棒方差姿态控制器能够保证良好的控制效果,鲁棒性强。     

飞机拦阻系统非线性控制仿真分析

针对飞机拦阻系统采用非线性控制进行了机构实现分析,利用状态反馈线性化及线性系统二次性能指标最优控制设计方法设计了非线性控制规律。建立了跟踪控制飞机位移及速度的非线性控制仿真模型,针对系统参数变化及飞机撞网速度测量值有偏差状况,进行了鲁棒性仿真分析,仿真结果表明:采用非线性控制,系统动态响应快,跟踪特性好,鲁棒性强,拦阻指标容易满足。     

Prescribed-Time Control of Stochastic Nonlinear Systems with Reduced Control Effort

A new prescribed-time state-feedback design is presented for stochastic nonlinear strictfeedback systems. Different from the existing stochastic prescribed-time design where scaling-free quartic Lyapunov functions or scaled quadratic Lyapunov functions are used, the design is based on new scaled quartic Lyapunov functions. The designed controller can ensure that the plant has an almost surely unique strong solution and the equilibrium at the origin of the plant is prescribed-time mean-square stable. After that, the authors redesign the controller to solve the prescribed-time inverse optimal mean-square stabilization problem. The merit of the design is that the order of the scaling function in the controller is reduced dramatically, which effectively reduces the control effort. Two simulation examples are given to illustrate the designs.     

离散模糊双线性关联大系统的广义H2分散控制

基于分段二次Lyapunov函数稳定性理论,研究了一类离散模糊双线性关联大系统广义H₂分散控制问题。模糊双线性关联大系统由J个相互关联的离散T-S模糊双线性系统组成。通过构造分段Lyapunov函数,给出了系统二次稳定的充分性条件。在此基础上,设计了广义H₂分散状态反馈控制器,使闭环系统广义H₂稳定,控制器的设计可以通过序列线性规划矩阵方法求解得到。仿真结果表明所提方法的有效性。     

基于自适应陷波器的主动隔振仿真研究

自适应陷波器可以对陷波频率处的信号进行有效衰减，而对其他频率的信号影响较小，因而在有源消声、信号提取等方面得到广泛应用。以与振动干扰同频率的正弦信号作为前馈控制系统的参考输入，采用滤波LMS算法对控制权值进行调整，证明对单频和多频干扰进行主动隔振时系统的结构均等同于自适应陷波器，因而可以对周期性振动进行有效的隔离。仿真结果表明，在振动干扰中存在随机噪声的情况下，所提出的控制方法对于周期性振动仍具有较好的控制效果。     

Global asymptotic regulation control for nonlinear systems with iISS inverse dynamics

This paper investigates a global asymptotic regulation control problem for a class of nonlinear systems with dynamic uncertainties.The requirement of a priori knowledge of control directions is removed and the inverse dynamics satisfy the weaker integral input-to-state stable condition.By application of the changing supply rates and the Nussbaum-type gain techniques,a partial state-feedback regulator is constructed.The main results demonstrate that the designed controller ensures the system state converges to the origin whereas the other signals of the closed-loop system are bounded. Simulation results are illustrated to show the effectiveness of the proposed approach.     

一类不确定时延的NCS的保性能控制律设计

采用工业通信网络的网络控制系统（networked control systems,NCS）具有开放性、速度快和强大的软硬件技术支持等优势,但不确定的网络时延对系统的稳定性和控制性能有着很大的影响。在实际的NCS中,不仅要求NCS稳定运行,而且还要求NCS满足一定的性能指标;同时,采用状态反馈是兼顾系统性能和敏感性的最有效的控制方式。针对一类具有不确定时延的状态反馈NCS,建模为不确定的线性时滞系统,利用Lyapunov理论和线性矩阵不等式（linear matrix inequality, LMI）方法研究NCS的保性能控制问题,给出NCS保性能控制律存在的条件和设计方法,最优保性能控制律的设计。     

水下超高速航行体双模态控制研究

水下航行体在高速运动时,其全部或大部分表面被空泡包裹.由于水动力和周围环境扰动使航行体尾部与空泡壁相互作用产生滑行力,滑行力的存在使系统具有较强的非线性并导致不稳定的航行状态.针对航行体纵向运动数学模型可以描述为无滑行力的线性模型和存在滑行力的非线性模型,设计了基于状态的切换控制策略并设计了双模态控制器,对于线性模型采用状态反馈控制,对于非线性模型采用基于微分几何的反馈线性化方法.仿真结果表明,基于状态切换的双模态控制器减小了滑行力,对于初始状态扰动具有鲁棒性.