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1.
尚芳  刘允刚  张承慧 《自动化学报》2007,33(12):1326-1331
研究了一类非线性增长速度依赖于不可测状态且有稳定零动态非线性系统的全局输出反馈渐近稳定控制问题. 因所研究的系统隐含有零动态, 所以首先定义了一系列新的线性变换, 从而成功地分离出原系统的零动态, 得到了便于输出反馈设计的新系统. 然后给出了变换后系统的较为简洁的输出反馈控制设计过程, 并且, 闭环系统的渐近稳定性可由所导出矩阵的正定性来保证. 最后, 仿真算例验证了文中理论结果的正确性.  相似文献   

2.
不确定非线性系统全局渐近自适应神经网络控制   总被引:1,自引:0,他引:1  
针对一类控制增益为一般函数形式的不确定仿射非线性系统,提出一种能够确保全局渐近稳定的自适应神经控制(adaptiveneural control,ANC)方法.为了保证神经网络逼近的适用性,设计一种可变控增益的比例微分(proportionaldifferential,PD)控制器以全局镇定被控对象.利用状态变换解决由未知控制增益函数导致的控制奇异问题.提出一种连续的自适应鲁棒控制项实现闭环系统的渐近跟踪.与现有的全局渐近跟踪ANC方法相比较,本文方法不仅简化了PD增益的选择,而且减轻了控制输入的颤振问题.仿真结果表明了本文方法的有效性.  相似文献   

3.
田慧慧  苏玉鑫 《控制与决策》2012,27(11):1756-1760
针对高度非线性多关节机器人的轨迹跟踪问题,提出一类输出反馈重复学习控制算法,使得在只有位置信息可测以及模型信息不确定的条件下即能获得良好的控制品质.非线性滤波器的引入解决了现实中速度信号较难获得的问题,重复学习控制策略实现了对周期性参考输入的渐近稳定跟踪.应用Lyapunov直接稳定性理论证明了闭环系统的全局渐近稳定性.三自由度机器人系统数值仿真结果表明了所提出的输出反馈重复学习控制的有效性.  相似文献   

4.
机器人系统全局渐近稳定非线性PD+轨迹跟踪控制   总被引:2,自引:0,他引:2  
采用一类具有“小误差放大、大误差饱和”功能的非线性饱和函数来改进常用的线性比例微分加(PD+)机器人系统动力学控制,以形成非线性PD+(NPD+)控制,从而获得更快的响应速度和轨迹跟踪精度.应用Lyapunov直接稳定性理论和LaSalle不变性原理证明了闭环系统的全局渐近稳定性.两自由度机器人系统数值仿真结果表明了所提出的NPD+控制具有良好的控制品质.  相似文献   

5.
机器人系统非线性分散重复学习轨迹跟踪控制   总被引:3,自引:2,他引:1  
田慧慧  苏玉鑫 《自动化学报》2011,37(10):1264-1271
采用一类具有"小误差放大、大误差饱和"功能的非线性饱和函数来改进传统重复学习控制(Repetitive control, RC)机器人系统动力学控制, 形成一类新的非线性分散重复学习控制(Nonlinear decentralized repetitive control, NRC),使得在不增加驱动力矩的条件下获得了更快的响应速度和更高的轨迹跟踪精度. 应用Lyapunov直接稳定性理论和LaSalle不变性原理证明了闭环系统的全局渐近稳定性. 三自由度机器人系统数值仿真结果表明了所提出的非线性分散重复学习控制具有良好的控制品质.  相似文献   

6.
本文针对机械手一类复杂的非线性系统,综合非线性补偿和模型参考自适应控制两种方法的基本思想,提出一种有效的全局渐近稳定自适应控制方案.此方案没有对机械手模型做任何线性近似,控制算法中只用到了容易测量的关节角位移和角速度信号,而且保证控制量平滑.最后给出了满意的仿真结果.  相似文献   

7.
牛国君  曲翠翠  潘博  付宜利 《机器人》2020,42(5):568-582
为解决传统饱和函数条件比较苛刻的问题,本文提出了一种饱和函数,并将其应用于线性PD(比例-微分)+非线性PI(比例-积分)控制律.应用李亚普诺夫稳定性定理和拉萨尔不变原理推导了非线性PID控制律全局渐近稳定条件.为提高非线性PID控制精度,以位置跟踪误差绝对值时间积分和关节力矩输出误差绝对值时间积分为目标函数,以全局渐近稳定性条件以及关节额定驱动力矩为约束条件,应用多目标遗传算法NSGA-II(non-dominated sorted genetic algorithm-II)进行非线性PID控制律参数整定.选择优化后位置跟踪误差绝对值时间积分最小的饱和函数,并研究含有该饱和函数的非线性PID控制律对模型不确定性、输入干扰力矩和噪声的鲁棒性.与传统PID控制律和含有传统饱和函数的非线性PID控制律相比,本文方法的位置跟踪精度分别提高了近2个数量级和1个数量级.提出的饱和函数在靠近平衡点处具有较强反作用,使误差快速收敛于平衡点,有助于提高非线性PID控制律的位置跟踪精度以及鲁棒性.  相似文献   

8.
本文讨论了一类具有未知函数和未知控制方向非线性系统的全局渐近稳定问题.通过提出一个引理处理未知函数问题,从而得到了一种基于反步法和Nussbaum增益技术的全局渐近稳定控制算法.与逼近方法处理未知函数的算法相比,本文提出的算法解决了非线性系统的全局渐近稳定问题;与现存解决非线性系统的全局渐近稳定控制算法相比,本文避免了使用未知函数的假设条件,因此降低了保守性.值得一提的是本文的算法也解决了反步法的“微分爆炸”问题,因此所提出的控制方案不仅仅得到了全局渐近稳定控制方案,而且降低了计算的复杂性.最后,将该方案应用到刚性单链杆机械手系统中,仿真结果验证了其有效性.  相似文献   

9.
一类非线性系统的全局渐近稳定和有限时间镇定   总被引:1,自引:0,他引:1  
针对一类全矩阵形式的非线性系统, 研究其全局稳定性及有限时间镇定问题. 首先, 全矩阵形式非线性系统被分成上三角形式和下三角形式非线性系统的加和, 并针对下三角形式非线性系统, 利用加幂积分方法, 自上而下地设计系统的全局稳定控制器; 其次, 在上面控制器作用下, 证明全矩阵形式系统在一个给定领域内是局部渐近稳定的; 最后, 运用自下而上的顺序, 一种嵌套饱和方法被用到上述控制器中, 通过调节饱和度, 使得闭环系统全局渐近稳定. 此外, 在适当的条件下, 可以得到全矩阵形式非线性系统的全局有限时间稳定性.  相似文献   

10.
针对一类含不确定参数的本质非线性系统,基于非光滑控制技术,提出了 一种基于采样控制的全局非光滑镇定方案. 首先,基于加幂积分技术和递归设计方法,提出了一类采样状态反馈控制器构造性设计方法.然后,通过合理地构造Lyapunvo泛函,严格地证明了存在一个最大采样周期 可以保证闭环系统的全局渐近稳定性. 由于控制器是离散形式的,所以在实际中易于用计算机来实现. 仿真结果验证了该方法的有效 性.  相似文献   

11.
This paper is concerned with PID position regulation of robot manipulators actuated by permanent magnet synchronous motors (PMSMs). We present a global asymptotic stability proof when the electric dynamics of these actuators is taken into account. Our controller is so simple that it differs from standard field oriented control (SFOC) of PMSMs in only three simple nonlinear terms that have to be added and a nonlinear PID controller which is used instead of a classical PID controller. Thus, our proposal represents the closest result to SFOC of PMSMs provided with a formal global asymptotic stability proof. We present an advancement, if modest, towards presenting a global stability proof for SFOC when used in robotics.  相似文献   

12.
This paper addresses the global finite-time regulation problem of robotic manipulators. A simple nonlinear proportional-integral-derivative (PID) control is proposed by adding a nonlinear proportional and derivative term to the commonly used PID controller. Lyapunov's stability theory and geometric homogeneity technique are employed to prove global finite-time stability. Advantages of the proposed control include the absence of modelling information in the control law formulation and the global finite-time stability featuring fast transient and high-precision positioning. Explicit conditions on the controller parameters to ensure global finite-time regulation stability are obtained. Simulations are presented to demonstrate the effectiveness and the improved performances of the proposed approach.  相似文献   

13.
一种新型非线性PID控制器及其参数设计   总被引:2,自引:0,他引:2       下载免费PDF全文
方法简单、参数效率高是非线性PID控制器所期望的特征. 本文提出一种新的非线性PID控制器设计方法,并就其非线性函数的函数特点以及控制器参数选择问题进行了分析. 首先, 利用电容极间场强的作用原理提出了一种非线性函数构造方法, 并用来对常规PID控制器进行修正, 形成一种非线性PID控制器; 其次, 对非线性函数进行了分析, 指出了不同参数对非线性函数的影响; 最后, 利用T–无源的有关结论对这种非线性PID控制器的稳定性进行分析, 得到了这一非线性PID控制器的参数设计依据. 仿真实例表明了文中所提控制  相似文献   

14.
Several nonlinear proportional-integral-derivative (PID) controllers for robot manipulators that ensure global asymptotic stability have been proposed in the literature. However, the tuning criteria obtained are expressed in terms of conditions so restrictive that they have avoided, until now, carrying out experimental tests with such controllers. Tuning criteria of some PID controllers for robot manipulators with conditions more relaxed than those presented previously in the literature have been proposed in two recent works by the authors. This was achieved by setting the tuning conditions individually for each joint instead of general conditions for the whole robot. In this paper we extend these results to a class of nonlinear PID global regulators for robot manipulators. The obtained tuning criteria are given in terms of conditions so relaxed that they have allowed to carry out, for the first time, experimental essays with these controllers. Such experiments are presented in this paper using a two-degrees-of-freedom robot manipulator.  相似文献   

15.
Proportional Integral Derivative (PID) controllers still represent the core control method for achieving output regulation of either linear or nonlinear systems in the majority of industrial applications. However, conventional PID control cannot guarantee specific state constraint requirements for the plant, when the system introduces uncertainties. In this paper, a novel nonlinear PID control that achieves output regulation and guarantees a desired state limitation below a given value for a wide class of nonlinear systems with constant uncertainties is proposed. Using nonlinear ultimate boundedness theory, it is shown that the proposed state‐limiting PID (sl‐PID) control maintains a given bound for the desired system states at all times, ie, even during transients, whereas an analytic method for selecting the controller gains is also presented to ensure closed‐loop system stability and convergence at the desired equilibrium. Two nonlinear engineering examples that include an electric motor and a dc/dc converter are investigated using the conventional PID and the proposed sl‐PID to validate the superiority of the proposed controller in achieving the desired output regulation with a given bounded state requirement.  相似文献   

16.
一类非线性PID控制系统稳定性分析   总被引:1,自引:0,他引:1  
针对一类由非线性增益函数与典型PID控制器级联组成的非线性系统,采用波波夫判据对此类闭环控制系统进行稳定性分析.分别确定了确保非线性PID,P,PI,PD闭环控制系统稳定的非线性增益的有效取值范围,为此类非线性控制系统的实际工程应用奠定了基础.  相似文献   

17.
一种新型模糊非线性PID控制器   总被引:4,自引:0,他引:4  
采用一维输入一维输出的模糊映射关系与传统PID控制器相级联的方式,构成一个模糊非线性PID控制器以提高现有PID控制器的性能.一维模糊控制器无需选择与调整量化因子和比例因子,采用五条规则,易于实现.数值仿真和误差泛函积分评价指标表明,所提出的模糊非线性PID控制器比现有控制器具有更好的动静态性能.  相似文献   

18.
This paper deals with proportional–integral–derivative (PID) controller design for nonlinear systems represented by local model networks. The proposed method is based on the concept of parallel distributed compensators where the scheduling of the local model network is adopted for the PID parameters. The proposed design method for nonlinear PID controllers considers closed-loop stability by means of a Lyapunov stability criterion as well as closed-loop performance. All PID parameters are determined by a multi-objective genetic algorithm (multiGA), which handles the trade-off between stability and performance. A simulation example demonstrates the effectiveness of the proposed method.  相似文献   

19.
The performance of linear and nonlinear temperature control schemes is assessed for an open-loop unstable gas-phase polyethylene reactor (GPPER), based on speed, damping, robustness and the ability to maintain closed-loop stability in different operating regimes. An existing industrial GPPER model is improved by modelling the temperature states in the external heat exchanger using linear and nonlinear driving force models with varying numbers of heat transfer stages. Differences in heat exchanger models do not produce gain mismatch but do result in phase mismatch. It is shown that the nonlinear error trajectory controller (ETC) exhibits significantly superior responses in terms of speed, damping and robustness compared with an optimally-tuned PID controller. Therefore, substantial benefits could be realized using nonlinear controllers because they can provide good disturbance rejection capabilities and ensure closed-loop stability over a wide range of operating conditions. An approach is presented for tuning ETCs for minimum-phase processes of arbitrary relative degree.  相似文献   

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