PID feedback for mixed H2/H∞ tracking control of robotic manipulators

The design objective of a mixed H2/H∞ control is to find the H2 optimal control law under aprescribed disturbance attenuation level. This paper addresses a optimal PID control law on the basis of the newsolution to mixed H2/H∞optimal control problem that provide much more flexible design compared to the existing works. Then a closed-form PID controller to mixed H2/H∞ robotic tracking problem is simply constructed and hence the design procedure is presented.Finally, numerical simulations illustrate the effectiveness of the optimal PID feedback design proposed in this paper via a two-link robotic manipulator.     

Novel l2-l∞ controller design for LPV discrete time-delay systems

One of the first attempts to derive energy-to-peak performance criteria and state-feedback controller design problem for linear parameter-varying discrete time systems with time delay is provided. Firstly, we present a parameterdependent l2-l∞ performance criterion using a parameter-dependent Lyapunov function. Upon the conditions addressed,an improved parameter-dependent l2-l∞ performance criterion is established by the introduction of a slack variable,which exhibits a kind of decoupling between Lyapunov functions and system matrices. This kind of decoupling enables us to obtain more easily tractable conditions for analysis and synthesis problems. Then, the corresponding parameter-dependent state-feedback controller design is investigated upon these performance criteria, with sufficient conditions obtained for the existence of admissible controllers in terms of parameterized linear matrix inequalities. Finally, a numerical example is provided to illustrate the feasibility and advantage of the proposed controller design procedure.     

Robust H2 control for uncertain sampled-data systems

A new approach is proposed for robust H2 problem of uncertain sampled-data systems. Through introducing a free variable, a new Lyapunov asymptotical stability criterion with less conservativeness is established. Based on this criterion, some sufficient conditions on two classes of robust H2 problems for uncertain sampled-data control systems are presented through a set of coupled linear matrix inequalities, Finally, the less conservatism and potential of the developed results are illustrated via a numerical example.     

Adaptive control for a class of discrete-time time-delay systems with regard to delay parameter

The memory state feedback control problem for a class of discrete-time systems with input delay and unknown state delay is addressed based on LMIs and Lyapunov-Krasovskii functional method. Under the action of our designed adaptive control law, the unknown time-delay parameter is included in memory state feedback controller. Using LMI technique, delay-dependent sufficient conditions for the existence of the feedback controller are obtained. Finally, the effectiveness of the proposed design method is demonstrated by a numerical example.     

Recoverability analysis of block-sparse representation

Recoverability of block-sparse signals by convex relaxation methods is considered for the underdetermined linear model. In previous works, some explicit but pessimistic recoverability results which were associated with the dictionary were presented. This paper shows the recoverability of block-sparse signals are associated with the block structure when a random dictionary is given. Several probability inequalities are obtained to show how the recoverability changes along with the block structure parameters, such as the number of nonzero blocks, the block length, the dimension of the measurements and the dimension of the block-sparse representation signal. Also, this paper concludes that if the block-sparse structure can be considered, the recoverability of the signals wil be improved. Numerical examples are given to il ustrate the availability of the presented theoretical results.     

Optimal fault detection for a class of discrete-time switched linear systems

This paper deals with the problem of optimal fault detection filter(FDF) design for a class of discrete-time switched linear systems under arbitrary switching.By using an observer-based FDF as a residual generator,the design of the FDF is formulated into an optimization problem through maximizing the H /H∞ or H∞/H∞ performance index.With the aid of an operator optimization method,it is shown that a mode-dependent unified optima solution can be derived by solving a coupled Riccati equation.A numerical example is given to show the effectiveness of the proposed method.     

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。     

Stochastic maximum principle for mixed regular-singular control problems of forward-backward systems

This paper considers a stochastic optimal control problem of a forward-backward system with regular-singular controls where the set of regular controls is not necessarily convex and the regular control enters the diffusion coefficient. This control problem is difficult to solve with the classical method of spike variation. The authors use the approach of relaxed controls to establish maximum principle for this stochastic optimal control problem. Sufficient optimality conditions are also investigated.     

考虑随机权重阈值的多态k/N系统任务可用度建模与优化

在权重阈值随机变化的条件下,现有多态系统可用度建模在实际工程应用中具有局限性.本文引入数量阈值并考虑权重阈值随机性,分析多态k/N系统中部件数量和权重不能彼此映射的问题,提出新的随机联合运算符结合通用生成函数的方法,建立系统任务可用度评价模型.本方法适用于权重阈值服从连续型随机分布的情形,优于传统递归算法.然后,分别构建系统可用性约束或成本约束下的系统优化模型,通过遗传算法编程,求解部件各状态的最优概率及权重.最后,以船舶运输系统为例阐述数量阈值对系统可用度的影响,并给出随机权重阈值下多态系统的设计优化结果.研究成果可为系统工程师开展可靠性设计和改进提供方法依据.     

Novel method based on ant colony opti mization for solving ill-conditioned linear systems of equations

1 .INTRODUCTIONStudies have shownthat some systems are highlysen-sitive :a small perturbationin the data can result in alarge changeinthe solutions .Such systems are calledill-conditioned systems .Ill-conditionedlinear systemsof equations have a wide application in many fieldssuch asi magine processing,deconvolution, model pa-rameters esti mation.Because the condition number ofill-conditionedlinear systems of equationsis very big,the data error andthe rounding error inthe computa-tional p…     

1/2-TRANSITIVE GRAPHS ASSOCIATED WITH LINEAR GROUPS

１／２－ＴＲＡＮＳＩＴＩＶＥＧＲＡＰＨＳＡＳＳＯＣＩＡＴＥＤＷＩＴＨＬＩＮＥＡＲＧＲＯＵＰＳ￥ＤＵＳｈａｏｆｅｉ（ＤｅｐａｒｔｍｅｎｔｏｆＭａｔｈｅｍａｔｉｃｓ，ＳｈａｎｘｉＵｎｉｖｅｒｓｉｔｙ，Ｔａｉｙｕａｎ０３０００６，Ｃｈｉｎａ）Ａｂｓｔｒａｃ...     

武器装备体系组合规划的高维多目标优化决策

针对武器装备体系组合规划问题中存在多类相互冲突的高维多目标问题(目标数 ≥ 5),提出了一种三阶段的集成优化决策方法. 首先运用目的规划技术将高维多目标问题转换为一般多目标优化模型(目标数 ≤ 3); 然后提出一种多目标差分进化算法,用于搜索属于决策者关心区间的非劣解集; 最后提出基于预测优化的理想点算法,可生成精确满足决策者偏好的最佳折衷解. 通过某侦察装备体系组合规划示例,证明了各算法模块的优势和该方法的整体有效性,可为武器装备发展和顶层规划提供决策支持.     

全氢罩式退火炉虚拟样机的开发

以全氢罩式退火炉(简称"全氢炉")为研究对象,分析了全氢炉内具体的燃烧、流动和传热传质过程,同时开发了反映全氢炉退火过程的数学模型,借助数值模拟方法进行了全氢炉虚拟样机的开发.该虚拟样机为全氢炉钢卷堆垛退火提供退火工艺制度预测之外,还为进行新退火工艺、新钢种的扩展和新炉型的开发和改造提供了模拟辅助试验分析平台.     

延迟N-策略Geo/G/1排队系统的队长分布及数值计算

考虑延迟N-策略离散时间Geo/G/1排队系统,使用全概率分解技术,从任意初始状态出发,研究了队长的瞬态和稳态性质,导出了在任意时刻n瞬态队长分布的z-变换的递推表达式和稳态队长分布的递推表达式,以及稳态队长的随机分解.最后,通过数值实例, 讨论了稳态队长分布对系统参数的敏感性,并阐述了获得便于计算的稳态队长分布的表达式在系统容量设计中有重要的价值.     

全氢罩式炉在线自适应优化仿真平台的开发

以全氢罩式退火炉(简称"全氢炉")为研究对象,分析了退火过程在线优化需求、现场监测布置情况和现场控制系统数据存储情况,建立了一套全氢炉退火过程在线自适应优化方法.结合已开发的全氢炉在线退火过程的数学模型和模拟仿真体系,借助数值模拟方法进行了全氢炉在线自适应优化仿真平台的开发.该仿真平台能够实现"人工在线启动优化"和"自适应在线启动优化"两种方式的响应,进行全氢炉冷轧钢卷退火过程的在线仿真,预测退火工艺制度的优化调整方案,同时也为新退火工艺、新钢种和新炉型的退火过程在线自适应优化的开发和改造提供了试验分析平台.     

M/G/1排队系统的性能灵敏度估计与仿真

对具有一般分布的排队系统-M／G／l排队系统给出了一种通过其嵌入Markov链来计算系统势能及性能导数的仿真算法。由于该算法基于分析系统的一条单一样本轨道，故可直接用于系统的控制与优化。最后提供一个数值例子来表明该算法的应用。     

G/M/1排队系统的性能灵敏度分析与仿真

对G／M／1排队系统，通过研究其嵌入Markov链，讨论了系统的稳态性能灵敏度分析问题，导出了系统的稳态分布与其嵌入Markov链的稳态分布之间的关系式，给出了用嵌入Markov链的势能表示的稳态性能灵敏度公式。并提出了通过嵌入Markov链来计算系统性能灵敏度的仿真算法，由于该算法基于系统的一条单一样本轨道，故可直接应用于系统的控制与优化。最后提供了两种具体的G／M／1排队系统的例子来说明该算法的应用。     

全氢炉在线退火性能评估及诊断仿真平台开发

以全氢罩式退火炉(简称"全氢炉")为研究对象,基于全氢炉退火传热过程和监控系统的特点,结合退火阶段设备的运行工艺和设备性能变化情况,合理引入过程能力指数计算分析方法,建立了一套完整的全氢炉在线退火性能评估分析及诊断技术,借助计算机仿真技术进行了全氢炉在线退火性能评估分析及诊断仿真平台的开发。该仿真平台能够实现全氢炉具体堆垛退火性能的在线评估分析,并能够对退火性能不足的环节进行故障诊断,提示故障排查和控制调节信息,以指导现场生产过程中进行具体的故障检修和控制调整。     

Design of control sequence of pulses for the population transfer of high dimensional spin 1/2 quantum systems

On the basis of the relationship between the Hamiltonian of spin 1/2 quantum system under control and the energy level structure and transitions, a radio frequency pulse sequence is designed using intuitive and half counter-intuitive sequences of pulse to transfer the population of the 3-qubit system coherently. The effectiveness of the designed control sequence is verified through the system simulation experiment of the evolution of state. In principle, the design method of the control pulse sequence proposed can be generalized to use in the quantum systems of higher dimension.