基于演算子理论的IPMC人工肌肉精确位置控制

IPMC（Ionic Polymer Metal Composite）人工肌肉是一种离子交换聚合金属材料;由于具有在低电压作用下可以产生较大弯曲的特性;已经被作为分布式传感器和执行器广泛应用于各种仿生机器人构建中。为了在各种仿生机器人中应用IPMC人工肌肉;期望的位置或偏移量必须能够精确地控制。针对这个问题;通过应用鲁棒右互质分解方法;本文设计一种基于演算子理论的IPMC人工肌肉精确位置控制系统;该系统不仅保证了鲁棒稳定性;而且能够实现精确的位置跟踪。最后;通过仿真和实验结果;系统的有效性进一步得到验证。     

基于演算子理论的液位控制系统应用研究

为了模拟工业锅炉液位过程控制,以水箱过程控制实验装置为基础进行了液位控制的实验研究。首先提出了基于演算子理论的右互质分解方法实现非线性控制系统的设计;接着以PCL-812PG数据采集卡为基础进行了数据采集与驱动设计;然后利用设计好的控制器在Visual C++开发环境下对该液位系统进行了实验研究;实验中液位设定值为300mm,结果显示液位控制系统上升时间小于260s,系统超调低于5%,满足要求的性能指标;实验结果表明了控制系统设计的有效性。     

Robust tracking control for operator-based uncertain micro-hand actuator with Prandtl–Ishlinskii hysteresis

Since the hysteresis property inherently exists in the rubber material, it is necessary to deal with the control issues for the micro-hand by considering the hysteresis property. Therefore, in this paper, the robust tracking control for the micro-hand systems is discussed from the aspect of the Prandtl–Ishlinskii hysteresis property which is more applicable for the real applications. Firstly, a new model is obtained by combining the dynamic model of the micro-hand with Prandtl–Ishlinskii hysteresis property. Secondly, a new stability condition based on bounded input and bounded output stability is proposed for the Prandtl–Ishlinskii hysteresis modeled micro-hand system from two different cases. Thirdly, by designing the robust controllers based on the internal model control method, the tracking performance can be improved by eliminating the effect from the disturbance. Finally, simulation is used to further demonstrate the effectiveness of the proposed design scheme.     

Operator-based robust control for nonlinear systems with Prandtl–Ishlinskii hysteresis

This article presents an operator-based robust control method for nonlinear systems with Prandtl–Ishlinskii (PI) hysteresis. On the existence of the hysteresis, the system usually exhibits undesirable oscillations and even instability. While addressing the hysteresis, PI model is adopted to describe it. Especially, the PI model is decomposed into two terms: an invertible part and a disturbance part. In this way, the invertible part could be considered as a part of the nonlinear system. Based on the concept of Lipschitz's operator and the robust right coprime factorisation condition, a robust control design scheme is given to guarantee the bounded input bounded output stability of the obtained system. Further, a tracking operator design method is given to ensure the control system output-tracking performance under the existence of the disturbance part. Numerical simulation results are presented to validate the effectiveness of the proposed method.     

一类新非线性控制方法:基于演算子理论的控制方法综述

以基于演算子理论的鲁棒右互质分解 (Operator-based robust right coprime factorization, RRCF) 为基础, 提出了一种较新的非线性鲁棒控制方法.本文将简述此方法的概念、 基本理论及其应用. 具体地说, 本文首先介绍此方法的起源与基本概念; 然后,讨论此方法在系统的鲁棒稳定性、 输出跟踪与故障检测方面的设计等问题;最后,介绍此方法的实际应用从而进一步证明其有效性.     

非线性互质分解方法中的系统核表示

主要介绍了非线性互质分解理论的最新研究动态—系统核表示 .从系统核表示与右互质分解的关系、概念提出之背景及其在 Youla参数的控制器构造方面所起的作用强调了其在非线性互质分解理论中的重要性 .同时也从互质分解的存在性、系统的稳定鲁棒性、系统辨识及观测器设计等各方面介绍了非线性互质分解方法在控制理论中的应用     

基于鲁棒右互质分解的直流伺服系统精确跟踪控制

对含有不确定性的直流伺服控制系统,通过应用鲁棒右互质分解方法,设计了一种基于鲁棒右互质分解的精确跟踪控制系统;通常情况下,直流伺服系统中存在诸如非线性特性及参数辨识引起的模型误差和外界扰动,在设计的控制系统中,未知模型误差和外界扰动对系统性能的影响都被看作直流伺服系统的不确定性;在考虑到这些不确定性情况下,设计了一种基于鲁棒右互质分解理论的精确跟踪控制;首先在考虑未知的不确定模型影响系统性能指标的情况下,设计了一种基于演算子理论的反馈控制结构,此结构可以消除不确定模型的影响,在此基础上,设计了基于鲁棒右互质分解的鲁棒精确跟踪控制系统,得出精确跟踪条件;仿真结果表明使用提出的方法可以有效地消除不确定性,使得伺服系统具有很强的鲁棒性和精确跟踪能力。     

非线性系统的有界增益分解

本文对一类典型结构的反馈控制系统,讨论了对象的有界增益稳定的右互质分解和闭环系统有界增益稳定性的关系,对存在有界增益右互质分解的系统,给出了一种镇定方案。并且研究了这种的鲁棒性。     

Perturbed nonlinear systems control using extended robust right coprime factorisation

In this paper, extended operator-based robust right coprime factorisation is investigated for dealing with a class of nonlinear systems with unknown bounded perturbations. First, a new kind of operator is introduced, by which operator-based right coprime factorisation approach is extended to consider the perturbed nonlinear systems. By regulating the exponent of the proposed operator, a broader class of nonlinear systems can be handled using the extended right coprime factorisation approach. Second, for guaranteeing robust stability of the perturbed nonlinear systems, feasible design schemes based on some sufficient conditions are discussed, which can reduce complicated calculation in control processing using a different unimodular operator. Finally, a simulation example is involved to illustrate the proposed design scheme for confirming the effectiveness of the proposed method.     

Robust stability of MIMO nonlinear uncertain systems using operator-based right coprime factorisation

In this paper, a class of multi-input–multi-output (MIMO) nonlinear systems with uncertainties is considered by using operator-based right coprime factorisation. First, based on proposed quotient operators, coupling effect of the MIMO nonlinear systems is discussed. Second, based on the operator-based right coprime factorisation approach, sufficient conditions for guaranteeing robust stability of the MIMO nonlinear systems with uncertainties are proposed by using a new unimodular operator. Finally, a simulation example is shown to illustrate the proposed design scheme for the MIMO nonlinear systems with uncertainties.     

基于演算子的热过程执行机构故障诊断系统设计

This paper proposes an operator based fault detection method for an actuator fault of an aluminum plate thermal process with input constraints. Operator-based robust right coprime factorization (RCF) approach is utilized in this method. After developing a mathematical model of the thermal process, a robust tracking operator system is designed for the process with input constraints. Following this, design of the fault detection system is given by using operator-based robust RCF approach. Finally, experiment is conducted to support the proposed design method.     

带非线性扰动的不确定多时变时滞系统H∞鲁棒稳定性

研究了带非线性扰动的不确定多时变时滞系统的H∞鲁棒稳定性．其中不确定项是范数有界的,非线性扰动满足线性约束．基于Lyapunov-Krasovskii泛函,根据矩阵不等式技术和非线性处理方法,提出了两个新的时滞稳定性的结果．最后给出了两个示例,表明本文提出的方法与存在的文献结果相比,具有较少的保守性和良好的有效性．     

A multiple controller structure and design strategy with stability analysis

This paper proposes a multi-controller structure for a plant and develops associated stability results. The main theoretical result of the paper is a quite simple necessary and sufficient condition for the closed-loop stability of the scheme. The result also specializes as a multi-controller generalization of the single controller Youla-Kucera theory for the class of all stabilizing controllers for a plant, and to known results concerning simultaneous stabilization. The plants considered are recursively expressed in terms of a set of approximations of frequency-shaped plant-model errors. The controllers in successive loops can be designed based on increasing refinement in model approximation, perhaps via on-line identification.An advantage of the proposed multi-controller strategy is that a number of various controller design techniques can be employed to achieve performance objectives which are not conveniently achievable by any one technique. A design example is included with first an LQG design applied for stabilization of a crude nominal model, and then an H^∞ optimal design, and finally an H² optimal design. The latter two designs are aimed at enhancing H^∞/H² performances. There could even be a further adaptive loop for on-line performance enhancement.