模糊PID控制器在穿梭车控制系统的应用

针对传统PID控制器参数整定不良、适应性差、控制精度不理想的现状,提出了动态过程中参数自适应的模糊PID控制系统.根据穿梭车所用直流伺服电机参数及穿梭车负载状况,建立穿梭车控制系统简化数学模型.使用Matab的Simulnk工具箱对穿梭车控制系统进行仿真研究.由仿真结果可知,采用自适应模糊PID控制器,控制系统调整时间变短,响应速度更快,具有较好的鲁棒特性.利用仿真得出的模糊控制规则表于穿梭车控制系统中进行在线PID自整定,应用表明,使用自适应模糊PID控制器可有效减小超调量,加快控制系统的调整时间,达到了良好的实际控制效果.仿真与实验结果表明自适应模糊PID控制器具有动态响应快、超调量小和抗干扰能力强等优点,是一种更加有效的控制策略.     

基于预测双反馈的3D打印机温度优化控制

针对FDM型3D打印机喷头温度控制系统的非线性、大滞后等特点,传统PID控制难以满足实际的性能要求.为提高控制系统性能,提出预测模型双反馈变论域分形模糊分数阶PID控制器.分数阶PID控制为系统提供更多的控制余度;变论域模糊控制的论域能够随着误差的变化而变化,实现不同时刻选择不同论域的模糊规则;短反馈算法的引入能够构成双层反馈控制,实现对喷头温度的快速、精准控制;系统反馈环节建立预测模型,实现更加精确的控制.针对变论域模糊分数阶PID控制器中参数选择,提出一种改进的鲸鱼算法进行参数优化,增强控制器的自适应能力.仿真结果表明,改进鲸鱼优化算法的预测模型双反馈变论域模糊分数阶PID控制的喷头温度控制系统较传统的PID控制具有更好的控制效果,系统响应速度快、抗干扰能力强、稳定性好,能够满足实际工业需求.     

交流伺服系统的复合控制研究与设计

结合传统PID控制和滑模变结构控制两者的优点,提出了交流伺服系统的PD和滑模变结构的复合控制,使系统有良好的鲁棒性.本文分析了交流电机的数学模型,着重设计了三个闭环系统控制器的设计.仿真实验表明控制器能够提高控制系统的静态、动态性能和鲁棒性.     

一种自整定PID参数的模糊控制系统的设计与仿真

如果无法建立被控对象的数学模型或者建立的数学模型不精确,基于模型的PID控制器就失去了用武之地.而模糊控制器直接采用语言型控制规则,出发点是现场操作人员的控制经验或相关专家的知识,不需要建立被控对象的精确数学模型数学模型,甚至不需要建立数学模型.本文设计了一种将模糊控制和PID控制结合起来的控制系统,利用模糊控制器实时整定PID控制器的参数,并用在MATLAB下仿真,得到阶跃响应曲线.这种模糊PID控制方法起到优化PID控制器的作用,可应用于对控制性能要求很高的控制系统中.     

基于改进粒子群算法的永磁同步电机PID控制器

为提高永磁同步电机系统的控制精度,提出一种使用改进粒子群算法优化的永磁同步电机PID控制器。首先建立永磁同步电机数学模型,然后采用改进粒子群算法对PID控制器参数进行优化,实现永磁同步电机参数在线辨识,最后采用仿真实验对其性能进行测试。仿真结果表明,相对于传统的永磁同步电机PID控制器,本文方法优化的永磁同步电机PID控制器改善了系统响应性能,能够使永磁同步电机获得良好的稳定性、鲁棒性和动态性能。     

机动弹头末制导模糊控制研究

机动弹头在末制导段的飞行参数随着飞行条件的变化而发生较大变化,呈现严重的非线性,给控制系统设计带来较大困难.结合模糊控制和PID控制的优点,从工程实用的角度出发提出了一种基于模糊PID控制器设计的方法.模糊控制系统对系统的参数变化有较强的适应能力,尤其适合于数学模型未知、非线性的、复杂的对象.模糊控制器可根据系统的误差和变化对PID控制器参数进行自动优化和调整,然后用同法设计导弹的俯仰通道模糊控制器,并与传统的PID控制器进行分析对比,最后在六自由度模型上进行仿真.仿真结果表明控制器能够满足机动弹头末制导控制系统要求.     

直驱永磁同步风电机组的PID控制器设计与仿真

该文以10 k W的直驱永磁同步风力发电机(PMSG)为具体对象,对直驱永磁同步风力发电机组进行建模及仿真研究,在Matlab/Simuliuk平台上建立永磁同步风力发电机组各个子系统的数学模型。在发电环节整体动态仿真模型的基础上,采用变转速变桨距角的控制策略,针对变桨距控制系统设计了PID控制器,并调节PID参数,较好地实现控制器的性能。     

直流电动机调速控制系统的仿真研究

研究直流调速系统控制性能优化问题,直流调速系统是一种具有时变性和非线性的复杂控制系统,无法建立精确数学模型,传统PID控制的控制效果依赖于被控对象的精确数学模型,传统PID无法动态适应直流调速系统,难以获得较高的控制精度.SVM具有非线性控制能力,不需要建立精确的直流调速系统数学模型就可以进行精确逼近,为提高了直流调速系统控制精度,提出一种支持向量机和传统PID相结合的直流调速系统控制方法(SVM-PID).通过支持向量机对传统PID控制器3个参数进行在线整定,使PID控制器能够适应直流调速系统非线性变化,从而实现对适应直流调速系统精确控制,最后采用仿真验证SVM-PID性能.仿真结果表明,SVM-PID较好的克服了传统PID控制器存在的不足,提高了系统的抗干扰能力,减小了系统的超调量,为提高控制系统的性能提供了依据.     

PID控制系统的参数选择研究及应用

简要介绍了PID控制器的原理及特点,指出了传统PID控制器参数选择方法存在的不足.为了提高控制系统的设计效率,提出了用Matlab对系统进行仿真分析来确定PID控制系统参数的方法.并通过对超磁致伸缩致动器控制系统的建模与仿真,详细地介绍了这种方法的具体应用,结果表明这种参数选择方法是有效的.     

基于改进的神经元PID的网络化控制系统

为了解决网络诱导时延给网络化控制系统(Networked Control Systems,NCSs)带来的不利影响,在分析Ethernet时延特性的基础上,提出了一种不依赖于网络诱导时延精确数学模型的改进的神经元PID控制器。该控制器利用单神经元实现自适应PID控制,利用神经元良好的学习能力克服网络化控制系统中不确定的网络诱导时延的影响。改进的神经元PID控制器根据有限的时延信息动态调整用于计算控制输出量的参数,该控制器还利用一种在线调整规则对神经元的比例系数进行在线更新,并针对Ethernet这类网络进行了仿真研究。仿真结果表明,所提出的方法能有效提高控制系统的性能。     

Only connect: teaching, technology and telesis

Abstract This paper describes an approach to the design of interactive multimedia materials being developed in a European Community project. The developmental process is seen as a dialogue between technologists and teachers. This dialogue is often problematic because of the differences in training, experience and culture between them. Conditions needed for fruitful dialogue are described and the generic model for learning design used in the project is explained.     

European Community policy and the market

Abstract This paper starts with some reflections on the policy considerations and priorities which are shaping European Commission (EC) research programmes. Then it attempts to position the current projects which seek to capitalise on information and communications technologies for learning in relation to these priorities and the apparent realities of the marketplace. It concludes that while there are grounds to be optimistic about the contribution EC programmes can make to the efficiency and standard of education and training, they are still too technology driven.     

一种自适应子融合集成多分类器方法

融合集成方法已经广泛应用在模式识别领域,然而一些基分类器实时性能稳定性较差,导致多分类器融合性能差,针对上述问题本文提出了一种新的基于多分类器的子融合集成分类器系统。该方法考虑在度量层融合层次之上通过对各类基多分类器进行动态选择,票数最多的类别作为融合系统中对特征向量识别的类别,构成一种新的自适应子融合集成分类器方法。实验表明,该方法比传统的分类器以及分类融合方法识别准确率明显更高,具有更好的鲁棒性。     

Avoiding semantic and temporal gaps in developing software intensive systems

Development of software intensive systems (systems) in practice involves a series of self-contained phases for the lifecycle of a system. Semantic and temporal gaps, which occur among phases and among developer disciplines within and across phases, hinder the ongoing development of a system because of the interdependencies among phases and among disciplines. Such gaps are magnified among systems that are developed at different times by different development teams, which may limit reuse of artifacts of systems development and interoperability among the systems. This article discusses such gaps and a systems development process for avoiding them.     

Designing economic np control charts: A programmed simulation approach

This paper presents control charts models and the necessary simulation software for the location of economic values of the control parameters. The simulation program is written in FORTRAN, requires only 10K of main storage, and can run on most mini and micro computers. Two models are presented - one describes the process when it is operating at full capacity and the other when the process is operating under capacity. The models allow the product quality to deteriorate to a further level before an existing out-of-control state is detected, and they can also be used in situations where no prior knowledge exists of the out-of-control causes and the resulting proportion defectives.     

The development of robot art

Going through a few examples of robot artists who are recognized worldwide, we try to analyze the deepest meaning of what is called “robot art” and the related art field definition. We also try to highlight its well-marked borders, such as kinetic sculptures, kinetic art, cyber art, and cyberpunk. A brief excursion into the importance of the context, the message, and its semiotics is also provided, case by case, together with a few hints on the history of this discipline in the light of an artistic perspective. Therefore, the aim of this article is to try to summarize the main characteristics that might classify robot art as a unique and innovative discipline, and to track down some of the principles by which a robotic artifact can or cannot be considered an art piece in terms of social, cultural, and strictly artistic interest. This work was presented in part at the 13th International Symposium on Artificial Life and Robotics, Oita, Japan, January 31–February 2, 2008     

Explanation and prediction: an architecture for default and abductive reasoning

Although there are many arguments that logic is an appropriate tool for artificial intelligence, there has been a perceived problem with the monotonicity of classical logic. This paper elaborates on the idea that reasoning should be viewed as theory formation where logic tells us the consequences of our assumptions. The two activities of predicting what is expected to be true and explaining observations are considered in a simple theory formation framework. Properties of each activity are discussed, along with a number of proposals as to what should be predicted or accepted as reasonable explanations. An architecture is proposed to combine explanation and prediction into one coherent framework. Algorithms used to implement the system as well as examples from a running implementation are given.     

Three Process Perspectives: Organizations, Teams, and People

This paper provides the author's personal views and perspectives on software process improvement. Starting with his first work on technology assessment in IBM over 20 years ago, Watts Humphrey describes the process improvement work he has been directly involved in. This includes the development of the early process assessment methods, the original design of the CMM, and the introduction of the Personal Software Process (PSP)^SM and Team Software Process (TSP){^SM}. In addition to describing the original motivation for this work, the author also reviews many of the problems he and his associates encountered and why they solved them the way they did. He also comments on the outstanding issues and likely directions for future work. Finally, this work has built on the experiences and contributions of many people. Mr. Humphrey only describes work that he was personally involved in and he names many of the key contributors. However, so many people have been involved in this work that a full list of the important participants would be impractical.     

基于复小波噪声方差显著修正的SAR图像去噪

提出了一种基于复小波域统计建模与噪声方差估计显著性修正相结合的合成孔径雷达(Synthetic Aperture Radar,SAR)图像斑点噪声滤波方法。该方法首先通过对数变换将乘性噪声模型转化为加性噪声模型,然后对变换后的图像进行双树复小波变换(Dualtree Complex Wavelet Transform,DCWT),并对复数小波系数的统计分布进行建模。在此先验分布的基础上,通过运用贝叶斯估计方法从含噪系数中恢复原始系数,达到滤除噪声的目的。实验结果表明该方法在去除噪声的同时保留了图像的细节信息,取得了很好的降噪效果。     

基于QTE的蒙古文显示机制研究与实现

蒙古语言是中国蒙古族使用的通用语言,由于蒙古文区别于其他文字的书写方式和其自身变形机制等特点,在很多通用的文字处理引擎中都不被支持。在嵌入式产品开发与应用领域中Linux加QTE已经成为流行方式。该文给出了一种在QTE环境上实现基于标准Unicode的蒙古文点阵显示和变形算法, 并自定义了支持蒙古文的QTE组件,扩展了QTE功能,为在Linux加QTE方式的嵌入式体系结构中处理蒙古文提供了一种解决方法。