基于学习及演算子理论的非线性系统控制方法综述

基于演算子理论的鲁棒右互质分解(operator-based robust right coprime factorization,ORRCF)方法可以有效地处理非线性系统的鲁棒镇定和跟踪问题。首先,简述本方法相关的概念和定义。其次,基于利普希茨范数、同构思想和无源性控制方法讨论了此方法在非线性系统的鲁棒稳定、鲁棒分解和无源性方面的主要结果。再次,基于指数迭代定理、内模控制方法和滑模控制方法分别讨论了非线性的跟踪、鲁棒容错跟踪和自适应跟踪问题。最后,介绍此方法的实际应用,从而进一步证明其有效性。     

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。     

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。     

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.     

基于互质因子摄动的系统非脆弱鲁棒解耦控制

研究对象和控制器存在互质因子不确定性时闭环系统鲁棒稳定和非脆弱鲁棒解耦控制问题,得到了闭环系统具有鲁棒稳定性和鲁棒解耦性能的充分条件,给出了鲁棒控制器的优化设计方法.     

基于互质因子摄动的反馈系统的鲁棒稳定性

考虑对象和控制器同时具有互质因子摄动时闭环系统的鲁棒稳定性问题,得到了闭环系统鲁棒稳定的充要条件并给出了鲁棒控制器的优化设计方法.     

基于控制受限的机器人鲁棒自适应位置调节

针对实际的控制系统中输入为有界的情况,研究了机器人系统存在未知参数以及外界干扰时的位置调节问题.基于李雅普诺夫稳定性理论,通过构造存储函数的过程中引入双曲正切函数向量和适当的辅助函数向量,提出了一种有界的鲁棒自适应控制器.所提出的控制器不仅保证了闭环系统的鲁棒稳定性,同时也满足了从干扰信号到跟踪误差评价信号所定义的增益性能指标,即保证了干扰抑制的有效性.最后,由两连杆机器人进行的仿真结果验证了该控制器的可行性.     

移动灰箱演算中强干扰问题的进一步控制

为了消除移动灰箱演算中的强干扰问题,Levi等人提出了安全灰箱演算.然而,安全灰箱演算中引入的反动作却带来了新的安全隐患.为了消除上述安全隐患,提出了鲁棒灰箱演算.鲁棒灰箱演算在依靠反动作解决强干扰问题的同时,利用反动作的参数明确了该反动作的使用对象,有效地消除了安全灰箱演算中的不安全因素.对防火墙跨越的描述和对多元异步(-演算的翻译显示鲁棒灰箱演算依然具有较强的类似移动灰箱演算和安全灰箱演算的表达能力.同时还就鲁棒灰箱演算的类型问题作了初步的探讨,给出并证明了一套可以描述进程和能力的移动性和线程数两个属性的类型系统.研究结果初步表明,鲁棒灰箱演算可以成为移动计算形式化描述中的有力工具.     

Robust stability of nonlinear plants with a non-symmetric Prandtl-Ishlinskii hysteresis model

In this paper, robust stability of nonlinear plants represented by non-symmetric Prandtl-Ishlinskii (PI) hysteresis model is studied. In general, PI hysteresis model is the weighted superposition of play or stop hysteresis operators, and the slopes of the operators are considered to be the same. In order to make a hysteresis model, a modified form of non-symmetric play hysteresis operator with unknown slopes is given. The hysteresis model is described by a generalized Lipschitz operator term and a bounded parasitic term. Since the generalized Lipschitz operator is unknown, a new condition using robust right coprime factorization is proposed to guarantee robust stability of the controlled plant with the hysteresis nonlinearity. As a result, based on the proposed robust condition, a stabilized plant is obtained. A numerical example is presented to validate the effectiveness of the proposed method.     

非线性系统基于HM模型的自适应鲁棒跟踪控制

研究了非线性系统的跟踪控制问题，基于HM模型对非线性系统进行描述，并将全局模糊模型表示成不确定系统形式。在满足匹配条件下，针对未知不确定界，采用自适应鲁棒控制器，利用自适应变量信息来补偿系统的不确定性信息，实现了非线性系统的渐近跟踪控制。一级倒立摆仿真实验，验证了方案的有效性。控制器结构简单，规则少，具有应用价值。     

基于IPMC 驱动的自主微型机器鱼

本文从微小型鱼类的运动和受力分析入手,基于人工肌肉IPMC（离子聚合物金属复合材料）的特性, 进行微型机器鱼的结构和控制系统的设计．在此基础上实现仿小型鱼类的各种运动模式,然后,讨论了IPMC 驱动 器推进效率的优化．实验结果证明,基于IPMC 的厘米级机器鱼是可行的：通过改变控制信号的频率和占空比,实 现微型机器鱼的速度控制;通过控制胸鳍和尾鳍,实现上浮、下潜、转弯、巡游等运动模式．最后从尾鳍推进器的结 构角度分析了如何提高推进效率．     

Nonlinear Control Method for Nonlinear Systems with Unknown Perturbations by Combining Left and Right Factorization

In this paper, nonlinear control design scheme for a class of nonlinear systems is proposed based on operator coprime factorization theory. In detail, two stable controllers are provided to design a Bezout identity by combining left factorization (not coprime) with right factorization. Based on the proposed design method, a realization approach to left coprime factorization for the nonlinear system is obtained, which provides an effective framework for constructing left coprime factorization. Meanwhile, internal‐output stability of the nonlinear system is guaranteed. After that, based on the obtained left coprime factorization, the cases of the nonlinear systems with perturbations are discussed for guaranteeing robust stability for the perturbed systems. For the perturbations, two different cases, known bounded perturbations and unknown bounded perturbations, are investigated from different viewpoints to analyze robust stability issue for the perturbed systems. Finally, a simulation example is given to confirm the effectiveness of the proposed design method.     

Operator-Based Robust Nonlinear Control for SISO and MIMO Nonlinear Systems With PI Hysteresis

In this paper, operator based robust nonlinear control for single-input single-output (SISO) and multi-input multi-output (MIMO) nonlinear uncertain systems preceded by generalized Prandtl-Ishlinskii (PI) hysteresis is considered respectively. In detail, by using operator based robust right coprime factorization approach, the control system design structures including feedforward and feedback controllers for both SISO and MIMO nonlinear uncertain systems are given, respectively. In which, the controller design includes the information of PI hysteresis and its inverse, and some sufficient conditions for the controllers in both SISO and MIMO systems should be satisfied are also derived respectively. Based on the proposed conditions, influence from hysteresis is rejected, the systems are robustly stable and output tracking performance can be realized. Finally, the effectiveness of the proposed method is confirmed by numerical simulations.      

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.     

Robust Control for Uncertain Nonlinear Feedback Systems Using Operator-based Right Coprime Factorization

The robust control issue for uncertain nonlinear system is discussed by using the method of right coprime factorization. As it is difficult to obtain the inverse of the right factor due to the high nonlinearity, the proving of the Bezout identity becomes troublesome. Therefore, two sufficient conditions are derived to manage this problem with the nonlinear feedback system as well as that with the uncertain nonlinear feedback system under the definition of Lipschitz norm. A simulation of temperature control is given to demonstrate the validity of the proposed method.      

Operator-Based Robust Nonlinear Free Vibration Control of a Flexible Plate With Unknown Input Nonlinearity

In this paper,a robust nonlinear free vibration control design using an operator based robust right coprime factorization approach is considered for a flexible plate with unknown input nonlinearity.With considering the effect of unknown input nonlinearity from the piezoelectric actuator,operator based controllers are designed to guarantee the robust stability of the nonlinear free vibration control system.Simultaneously,for ensuring the desired tracking performance and reducing the effect of unknown input nonlinearity,operator based tracking compensator and estimation structure are given,respectively.Finally,both simulation and experimental results are shown to verify the effectiveness of the proposed control scheme.     

基于模糊自适应滑模算法的多机械臂力/位混合控制

针对多机械臂力/位混合控制受摩擦力等不确定因素影响的问题,该文提出了一种基于模糊自适应鲁棒滑模算法的控制方法。首先,根据机械臂及物体的动力学方程,构建多机械臂系统模型,并将模糊算法与自适应滑模算法相结合;然后,对不确定因素及未知非线性项进行补偿,利用鲁棒算法对系统可靠性进行提升;最后,基于李雅普诺夫方法,证明了该系统的稳定性。仿真结果显示,该方法可显著提升控制器的控制精度和系统响应速度。