一类非线性时滞系统的鲁棒自适应控制

针对一类含有非线性参数的非线性时滞系统．利用参数分离技术和后推方法,提出了一种自适应状态反馈控制方案,保证闭环系统的所有信号全局一致有界。通过构造Lyapunov—Krasoviskii泛函证明了系统的状态能收敛到零的一个小邻域内。     

MIMO离散非线性系统的自适应Backstepping控制

研究MIMO离散非线性系统的自适应Backstepping控制,对包含两个三阶子系统的MIMO系统推出稳定的自适应控制器设计,并利用关键性引理和投影算法的性质证明了闭环系统的所有信号有界和保证跟踪性能.     

一类不确定非线性系统的输出跟踪控制设计

设计了一类不确定非线性系统的鲁棒输出跟踪控制器,这类非线性系统含有有界干扰项和不确定参数。所设计的控制器在输出状态有界的假设条件下能保证系统输出信号渐近跟踪所期望的信号,并给予了证明。设计方法采用了Backstepping方法。     

基于RBF神经网络的不确定机械臂自适应反演控制研究

针对机械臂位置跟踪问题,基于RBF神经网络控制理论,提出了一种自适应反演控制方法．该方法利用反演控制技术解决了系统的非线性问题,通过神经网络对系统中不确定函数进行逼近,实现神经网络自适应反演控制,最后通过Lyapunov稳定性理论证明所得闭环系统的最终一致有界．仿真结果证明该算法的有效性．     

控制系数未知的一类链式时滞系统的鲁棒控制

针对控制系数未知的一类时滞链式系统,基于State-scaling变换技巧和Backstepping方法,通过构造积分型Lyapunov-Krasovskil泛函巧妙处理时滞项,设计鲁棒控制器,保证闭环系统的所有状态渐近稳定．     

非线性不确定系统鲁棒自适应动态面控制

本文针对具有未知参数不确定和干扰的严格反馈型的非线性系统鲁棒自适应控制提出了一种新的设计方法 ,即动态面控制 .传统的递推算法要求对建模的非线性反复多次微分 .本文方法由于加入了n个低通滤波器使得算法不用对模型非线性进行多次微分 ,因而避免了因“微分项的爆炸”引起的算法复杂性从而简化了算法 .理论分析证明了所设计的鲁棒自适应动态面控制器保证了闭环系统的半全局渐近稳定并且使得输出跟踪期望轨迹 .仿真结果表明了所设计的控制器的有效性和可行性 .     

Robust adaptive controller design for a class of nonlinear systems with unknown high frequency gains

INTRODUCTIONMany researchers have devoted their energy to the development of nonlinear system with unknown control directions during the past few years. The class of nonlinear system has been developed greatly since Mudgett and Morse (1985) relaxed the assumption that the unknown multiplicative terms are not only sign-invariant but also have known signs. A method called correction vector approach was proposed in (Lozano et al., 1990) and has been applied to design adaptive controller of …     

基于DSC的自适应补偿神经网络控制

针对一类可转化为“标准块控制形”的MIMO非线性系统,基于动态面控制技术,提出一种鲁棒自适应神经网络控制算法。采用径向基函数神经网络逼近不确定性模型,通过引入一阶滤波器,消除后推设计中由于反复对虚拟控制的求导而导致的复杂性问题,同时补偿项的引入可避免反馈线性化方法中可能出现的控制器奇异性问题,无需控制增益矩阵正定、可逆的条件。利用李亚普诺夫方法,证明了闭环系统是半全局一致终结有界,适当选取设计常数,跟踪误差可收敛到原点的一个小邻域内。计算机仿真结果表明此法的有效性。     

Adaptive backstepping sliding mode control for nonlinear systems with input saturation

An adaptive backstepping sliding mode control is proposed for a class of uncertain nonlinear systems with input saturation.A command filtered approach is used to prevent input saturation from destroying the adaptive capabilities of neural networks (NNs).The control law and adaptive updating laws of NNs are derived in the sense of Lyapunov function,so the stability can be guaranteed even under the input saturation.The proposed control law is robust against the disturbance,and it can also eliminate the impact of input saturation.Simulation results indicate that the proposed controller has a good performance.     

Adaptive terminal sliding mode control for high-order nonlinear dynamic systems

An adaptive terminal sliding mode control (SMC) technique is proposed to deal with the tracking problem for a class of high-order nonlinear dynamic systems. It is shown that a function augmented sliding hyperplane can be used to develop a new terminal sliding mode for high-order nonlinear systems. A terminal SMC controller based on Lyapunov theory is designed to force the state variables of the closed-loop system to reach and remain on the terminal sliding mode, so that the output tracking error then converges to zero in finite time which can be set arbitrarily. An adaptive mechanism is introduced to estimate the unknown parameters of the upper bounds of system uncertainties. The estimates are then used as controller parameters so that the effects of uncertain dynamics can be eliminated. It is also shown that the stability of the closed-loop system can be guaranteed with the proposed control strategy. The simulation of a numerical example is provided to show the effectiveness of the new method. Project supported by the National Outstanding Youth Science Foundation of China (NSFC:69725005) and the Zhejiang, Provincial Natural Science Key Foundation of China (ZD9905)     

Interval standard neural network models for nonlinear systems

INTRODUCTION Neural networks have been successfully em- ployed for controlling nonlinear systems since the 1990’s (Narendra and Parthasarathy 1990; Hunt et al., 1992; Suykens et al., 1996). In these nonlinear control systems, neural networks have been used either for modelling the system to be controlled, or for design- ing a controller, or both. Recently, the robustness issue has been an important focus of research in neuro-control circles (Suykens et al., 1996; Wams et al., 1999; Aya…     

一类非线性不确定时滞系统的鲁棒性

利用LMI求解了一类非线性不确定时滞系统的鲁棒性．在非线性不确定性满足增益有界条件下，讨论了自由系统的稳定性问题，构造了无记忆状态反馈控制器来镇定系统并且使系统具有一定的鲁棒性．     

Stabilization of stochastic nonholonomic systems

INTRODUCTION In recent years, much progress has been made in the design of control laws for systems subjected to nonholonomic constraint making it impossible to stabilize the system by any time-invariant continuous state feedback control law. This fact stimulates re- searchers to construct time-varying (Jiang and Ni- jmeijer, 1999; Jiang, 2001; Samson, 1995; Tian and Li, 2002) or discontinuous (Chang and Chen, 2002; Ge et al., 2003; Hu et al., 2004; Kim and Tsiotras, 2002; Mnif, 2004;…     

一类相似组合系统分散自适应模糊控制

针对一类具有函数控制增益的非线性相似组合大系统,基于一种修改的李亚普诺夫函数并利用Ⅱ型模糊系统的通用逼近能力,提出了一种稳定自适应分散模糊控制器设计的新方案。该方案能够避免现有的一些模糊控制器设计中对控制增益一阶导数上界的要求。通过理论分析,证明了闭环分散模糊控制系统是全局稳定的,跟踪误差收敛到零。     

一类不确定时滞链式系统的鲁棒控制

研究了一类含有时滞的链式系统的鲁棒控制问题.基于State-sealing变换技巧和Backstepping方法,通过构造积分型Lyapunov-Krasovskii泛函设计控制器保证闭环系统的所有状态渐近稳定.     

基于积分型李亚普诺夫函数的直接自适应模糊控制

针对一类具有未知下三角形函数控制增益矩阵的非线性系统，根据滑模控制原理，并利用I型模糊系统的逼近能力，提出了一种直接自适应模糊控制器设计的新方案．通过引入积分型李亚普诺夫函数及逼近误差自适应补偿项，证明了闭环系统是全局稳定的，跟踪误差收敛到零．仿真结果表明了该方法的有效性．     

一类MIMO非线性系统的H∞回路成形控制

针对一类多输入多输出非线性系统,基于H∞回路成形控制器设计方法,提出了一种新的鲁棒控制方案.分析了实际工业控制中生产过程的复杂性,运用H∞回路成形理论设计了控制器,总结了H∞回路成形控制器的特点.最后,在MATLAB环境下对某MIMO系统进行了仿真实验,比较了各种控制方案的性能,仿真结果表明该控制方案的优越性.     

Active disturbance rejection control for hydraulic width control system for rough mill

The highly nonlinear behavior of the system limits the performance of classical linear proportional and integral (PI) controllers used for hot rolling. An active disturbance rejection controller is proposed in this paper to deal with the nonlinear problem of hydraulic servo system in order to preserve fast response and small overshoot of control system. The active disturbance rejection (ADR) controller is composed of nonlinear tracking differentiator (TD),extended state observer (ESO) and nonlinear feedback (NF) law. An example of the hydraulic edger system case study is investigated to show the effectiveness and robustness of the proposed nonlinear controller,especially,in the circumstance of foreign disturbance and working condition variation,compared with classic PI controller.     

一类不确定非线性广义时滞系统的鲁棒控制与保性能控制

研究了不确定非线性结构扰动的广义系统的鲁棒控制和保性能控制问题．目的是分别设计系统的鲁棒控制器和保性能控制器。应用线性矩阵不等式方法,分别给出了系统的鲁棒控制器和保性能控制器存在的充分条件;并在这些条件可解时,分别给出了鲁棒控制器和保性能控制器的表达式。最后用例子说明了所给方法的应用．