共查询到19条相似文献,搜索用时 109 毫秒
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针对传统迭代学习控制在面临新的环境或控制任务时学习时间长、收敛速度慢的问题,首先引入迭代学习初始控制算法,并给出了算法收敛的充分必要条件;然后,利用小脑模型连接控制网络(CMAC)与反馈PID网络进行综合,在系统的历史控制经验基础上,估计系统的期望控制输入,作为迭代学习控制器的初始控制输入,再由开闭环P型迭代学习律逐步改善控制效果,从而避免了对初始控制输入量的盲目选择,使得系统的实际输出只需较少的迭代次数就能达到跟踪的精度要求。机器人系统的仿真结果表明了该算法的可行性与有效性。 相似文献
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本文针对以往单纯采用迭代学习控制引起的系统初始转矩冲击和收敛时间过长的问题,提出了一种新的基于经验数据的学习控制算法。指出影响系统输出的关键因素是舵机的转速。然后根据这个特点,应用迭代学习控制的经验,设计了一种简单的算法来确定迭代学习控制的初始输入量,再利用神经网络学习算法修正偏差。仿真结果表明基于经验数据的学习控制很好的解决了单纯采用迭代学习控制而引起的初始转矩冲击和收敛时间过长的问题。 相似文献
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非线性系统迭代学习算法 总被引:27,自引:1,他引:27
对于一个未知的非线性连续系统或离散系统,从任给的一个初始控制出发,尝试实现一条
给定的输出目标轨线.在满足一定条件下,利用跟踪误差来修正控制函数,经过反复的迭代学
习可以取得满意的效果.本文改进了Arimoto、Togai和Bien等的开环迭代学习的收敛条
件,并提出闭环迭代学习算法.理论与仿真结果证明了闭环算法在收敛条件、速度和抗干扰能
力上都优于开环算法. 相似文献
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针对P型迭代学习算法对初始偏差和输出误差扰动敏感,以及PD型迭代学习算法容易放大系统噪声,降低系统鲁棒性的问题,研究了具有任意有界扰动及期望输出的重复运行非线性时变系统的PD型迭代学习跟踪控制算法.利用迭代学习过程记忆的期望轨迹、期望控制以及跟踪误差,给出基于变批次遗忘因子的学习控制器设计,并借助λ范数理论和Bellman-Gronwall不等式,讨论保证闭环跟踪系统批次误差有界的学习增益存在的充分必要条件,及分析控制算法的一致收敛性.本算法改善了系统的鲁棒性和动态特性,单关节机械臂的跟踪控制仿真验证了方法的有效性. 相似文献
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迭代学习算法广泛应用于机器人轨迹跟踪控制研究中.常规迭代学习算法要求每次迭代的初始条件都相同,针对一类强耦合非线性系统在有限时间内重复运动的特征,提出了一种带有任意初态学习率的迭代算法.这种算法允许迭代时初始状态处于任意位置,通过数学计算证明了系统在不同初始态条件下的迭代学习算法,系统输出可以完全跟踪期望轨迹.这种带有... 相似文献
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时滞非线性系统的采样迭代学习控制 总被引:1,自引:0,他引:1
针对一类输入时滞非线性系统, 提出了一种采样迭代学习控制算法, 该算法不含跟踪误差的微分信号, 给出了学习算法收敛的充分条件, 当不存在初始误差、不确定扰动时, 算法在采样点处能实现对期望输出信号的完全跟踪, 否则, 跟踪误差一致有界, 仿真结果表明了该算法的有效性. 相似文献
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This article tries to handle the alignment initial condition for contraction mapping based iterative learning control, such that the system can operate continuously without any initial condition reset. This goal is achieved for a class of nonlinear systems through the proposed conditional learning control, which has several advantages over the alternative method, adaptive learning control. The conditional learning control guarantees that sufficient knowledge can be learned to update the input and achieve perfect output tracking, despite the non-identical initial conditions. The sufficient conditions of either monotonic or strictly monotonic convergence of the input sequence, and the choice of learning gains are given. The performance of the proposed method is illustrated by simulated examples. 相似文献
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As a powerful tool for solving nonlinear complex system control problems, the model-free reinforcement learning hardly guarantees system stability in the early stage of learning, especially with high complicity learning components applied. In this paper, a reinforcement learning framework imitating many cognitive mechanisms of brain such as attention, competition, and integration is proposed to realize sample-efficient self-stabilized online learning control. Inspired by the generation of consciousness in human brain, multiple actors that work either competitively for best interaction results or cooperatively for more accurate modeling and predictions were applied. A deep reinforcement learning implementation for challenging control tasks and a real-time control implementation of the proposed framework are respectively given to demonstrate the high sample efficiency and the capability of maintaining system stability in the online learning process without requiring an initial admissible control. 相似文献
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本文针对具有迭代初始误差的高相对度线性多变量离散系统,提出了一种P型的迭代学习控制算法.通过将迭代学习控制系统的二维运动过程描述为一维的线性离散系统,证明了该迭代学习控制算法的收敛性及其收敛的充要条件.该迭代学习控制算法通过对系统前次重复运动过程中的输入和跟踪误差信号进行学习,来不断地调整输入量,使得系统在经过一定次数的学习以后,在初始时间点以外的实际输出趋于期望输出.数值仿真结果表明了所提出算法的有效性. 相似文献
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In this work, an initial state iterative learning control (ILC) approach is proposed for final state control of motion systems. ILC is applied to learn the desired initial states in the presence of system uncertainties. Four cases are considered where the initial position or speed is a manipulated variable and the final displacement or speed is a controlled variable. Since the control task is specified spatially in states, a state transformation is introduced such that the final state control problems are formulated in the phase plane to facilitate spatial ILC design and analysis. An illustrative example is provided to verify the validity of the proposed ILC algorithms. 相似文献
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针对一类含非参数不确定性的非线性系统,提出一种鲁棒迭代学习控制算法,该算法放宽了常规迭代学习控制方法的初始定位条件,迭代初值可任意取值.基于类Lyapunov方法设计误差轨迹跟踪控制器,通过鲁棒限幅学习机制对不确定性进行估计和补偿,能够在整个作业区间上实现误差对给定期望误差轨迹的精确跟踪,期望误差轨迹根据迭代起始时刻的误差值设置.利用期望误差轨迹的衰减性状,可使系统误差在预设的时间点后收敛于原点的邻域内,邻域半径的大小可根据需要任意设置.理论分析和仿真结果表明了控制方法的有效性. 相似文献
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本文针对一类在有限时间内执行重复任务的不确定非线性系统状态跟踪问题,提出一种自适应滑模迭代学习控制方法,在存在初始偏移的情况下也能实现对参考轨迹的完全收敛.本文通过设计全饱和自适应迭代学习更新律,估计参数和非参数不确定性以及未知期望控制输入,并将估计值限制在指定界内,避免估计值的正向累加.文章设计的自适应滑模迭代学习控制方法对系统模型的信息需求少,在对系统非参数不确定性的上界估计时不需要Lipschitz界函数已知.本文给出严格的理论分析,证明闭环系统所有信号的一致有界性以及跟踪误差的一致收敛性,并通过仿真验证所提控制方法的有效性. 相似文献
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Byungyong You 《Control Engineering Practice》2011,19(3):234-242
In this paper, an iterative learning control (ILC) method is introduced to control molten steel level in a continuous casting process, in the presence of disturbance, noise and initial errors. The general ILC method was originally developed for processes that perform tasks repetitively but it can also be applied to periodic time-domain signals. To propose a more realistic algorithm, an ILC algorithm that consists of a P-type learning rule with a forgetting factor and a switching mechanism is introduced. Then it is proved that the input signal error, the state error and the output error are ultimately bounded in the presence of model uncertainties, periodic bulging disturbances, measurement noises and initial state errors. Computer simulation and experimental results establish the validity of the proposed control method. 相似文献
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初态学习下的迭代学习控制 总被引:3,自引:1,他引:2
提出一种新的初态学习律,以放宽常规迭代学习控制方法的初始定位条件.它允许一定的定位误差,在迭代中不需要定位在某一具体位置上,使得学习控制系统具有鲁棒收敛性.针对二阶LTI系统,给出了输入学习律及初态学习律的收敛性充分条件.依据收敛性条件,学习增益的选取需系统矩阵的估计值,但在一定建模误差下,仍能保证算法的收敛性.所提出的初态学习律本身及其收敛性条件均与输入矩阵无关. 相似文献