不确定未知界的相似组合系统分散自适应输出反馈控制

研究一类具有加性振动的不确定相似组合大系统的分散自适应输出反馈镇定问题,给出了该系统输出反馈镇定的条件。受控系统的不确定项可以是非线性的或时变的,输入通道不确定性满足一般限制,系统的不确定项的界是存在的但却是未知的。所设计的确定性非线性控制器能保证受控系统渐近收敛于系统的平衡点,并且自适应律保持有界。最后进行了仿真研究,表明所得结论是正确脯效的。     

不确定离散时滞系统的保性能控制

针对一类具有范数有界不确定性和状态滞后的离散时间线性系统,结合一个二次型 性能指标,采用线性矩阵不等式方法,提出了无记忆状态反馈保性能控制律的存在条件,并利 用一个线性矩阵不等式的解给出了保性能控制律的一个参数化表示.     

非周期时变非线性系统自适应迭代学习控制

对一类含有非周期时变不确定性的非线性系统的控制问题进行了研究。该系统具有严格反馈形式且控制增益未知。在控制器设计中,用一种具有迭代特性的神经网络消除了非周期时变不确定性的影响,并综合应用反演技术和鲁棒自适应控制技术消除了严格反馈结构和未知控制增益带来的设计问题。稳定性分析结果表明:系统所有状态量有界且输出量在积分意义下收敛到期望轨迹。仿真试验证明了所设计控制器的有效性。     

非匹配不确定高阶非线性系统的滑模控制新方法

对具有非匹配不确定的高阶非线性系统,采用改进的高阶滑模微分器获取已知状态的任意阶微分估计值,再以恰当阶次的状态微分估计值之差,得到非匹配不确定项及其微分的估计值,证明了其误差任意小.为避免奇异性和抖振,采用两种方案设计了滑模控制器,并设计鲁棒项提高系统鲁棒性.基于Lyapunov~论证明了系统稳定性.同现有其他方法相比,该方法具有适用范围更广、收敛速度快、控制精度高、运算量小、保守性低等优点.最后仿真证明了本文所有结论.     

一类非线性系统的多面滑模控制器设计

针对一类非线性系统，提出了一种基于模糊小脑关联结构模型(CMAC)神经网络的多面滑模变结构控制算法，其特点是无需已知不确定性函数及其各阶导数的上界，并且允许控制矩阵存在不确定性．用Lyapunov稳定性定理证明了系统的状态及权值误差最终一致有界．与经典设计方法相比，所提出的方案允许非参数化不确定性．仿真实例显示了方法的有效性．     

防洪堤结构风险计算模型探讨

本文根据防洪堤运行的实际，定义了防洪堤结构的风险，并提出了防洪堤结构风险计算的数学模型；其次，分析了土体的物理力学等的不确定性，并用MC方法计算防洪堤结构的不确定性.算例结果表明，防洪堤结构风险相对于水文风险而言是不能忽视的。     

Delay-dependent robust stability for neutral systems with mixed discrete-and-neutral delays

This paper focuses on the problem of delay-dependent robust stability of neutral systems with different discrete-and neutral delays and time-varying structured uncertainties. Some new criteria are presented, in which some flee weighting matrices are used to express the relatiomhips between the terms in the Leibniz-Newton formula. The criteria include the information on the size of both neutral-and-discrete delays. It is shown that the present results also include the results for identical discrete-and-neutral delays as special cases.A numerical example illustrates the improvement of the proposed methods over the previous methods and the influences between the discrete and neutral delays.     

一类不确定非线性系统的状态参考自适应滑模控制

针对一类非匹配不确定非线性系统。基于状态参考自适应控制算法和滑模控制策略。提出了状态参考自适应反演滑模控制方案，实现了不确定非线性系统的鲁棒输出跟踪。与现有的控制器设计相比，大大降低了控制系统阶次，允许系统存在非参数化的不确定性和未知扰动，增强了控制系统鲁棒性。仿真算例证明了理论研究成果的正确性和鲁棒性。     

Delay-dependent criteria for robust stability of time-varying delay systems

This paper deals with the problem of delay-dependent robust stability for systems with time-varying structured uncertainties and time-varying delays. Some new delay-dependent stability criteria are devised by taking the relationship between the terms in the Leibniz-Newton formula into account. Since free weighting matrices are used to express this relationship and since appropriate ones are selected by means of linear matrix inequalities, the new criteria are less conservative than existing ones. Numerical examples suggest that the proposed criteria are effective and are an improvement over previous ones.     

Adaptive backstepping control for an n-degree of freedom robotic manipulator based on combined state augmentation

The aim of this paper is to improve the tracking performance of a robotic manipulator by designing an adaptive controller and implementing it on the system. The proposed controller guarantees the system stability as well as good tracking performance in existence of nonlinearity and parameter uncertainties. The requirement to decrease the system response overshoot and steady state error as well as increasing speed of tracking for manipulators is essential to many manufacturers. To this mean, in this paper, the tracking error equations for an n-DOF manipulator are derived and the response characteristics are improved by augmenting a new state to the system equations. The stability of the closed-loop system is guaranteed based on the Lyapunov theory via backstepping control approach. The robotic manipulator model contains parametric uncertainties and many of the parameter values are unknown. To solve the problem, an adaption law is proposed via adaptive backstepping mechanism. Different experiments are carried out for a 2-DOF manipulator to show the effectiveness of the proposed approach and the results are compared with four of the recently revealed researches on control. Experimental results present the superiority of the state augmented adaptive backstepping in tracking the desired joint angles. Moreover, in order to present the industrial application of the proposed control method, it is simulated for a large industrial Scara manipulator.