高频响下音圈电机迟滞特性的建模与控制

优化数控机床给进定位精度问题,音圈电机(Voice Coil Motor,VCM)在高频、高速、高加速情况下,存在的迟滞特性影响系统的性能特性.为了实现青圈电机的精确定位控制,提出了音圈电机复杂迟滞神经网络动态逆模型的控制方法.首先,建立了音圈电机复杂迟滞神经网络动态模型,根据迟滞的特性求出了音圈电机复杂迟滞神经网络动态逆模型,采用逆模型结合PD控制算法进行仿真.实验结果表明,系统最大跟踪误差减少到是1.6％,表明所提出的控制方法有效地消除了音圈电机复杂迟滞的影响,提高了音圈电机的控制定位精度.     

近红外光谱干涉仪高精度运动控制器设计

介绍一种以DSP TM320VC5402为核心的近红外光谱干涉仪中的音圈电机数字闭环控制方法.采用增量式数字PID控制策略,实现音圈电机匀速运动控制.该系统通过实验验证,达到速度偏差为满量程小于0.5%的控制精度要求,能够满足近红外光谱干涉仪动镜的精确匀速运动控制要求.     

TMS320C2X DSP电机控制系统的动态数据交换

介绍了基于TMs320C2X数字信号处理器电机控制系统的动态数据交换方法,该方法可以利用DSP上的异步串行通信模块(SCI),通过运行于PC上的控制终端灵活地调整电机的工作状态(停止/使能/运行)、改变控制器的控制环节、设置控制环节参数(位置/速度/电流各环节PID参数)以及实时检测并显示各变量(速度、速度误差、位置误差等).实验验证了该方法的正确性.     

主从结构超精密运动平台的宏微控制系统设计

本文对超精密运动平台宏微控制系统进行了设计,并分析对比了两种主从结构的宏微策略,确定了宏动跟随微动的设计方案.针对光刻机宏微模型耦合部分引起的平台运动控制误差,本文引入了线性状态观测器对其进行补偿,并针对微动台音圈电机位置伺服系统设计了线性扩张状态观测器来实现对干扰的抑制.实验结果表明,加入线性状态观测器能够提高宏微控制系统的控制性能.     

基于PMAC的智能药房上药控制系统设计

针对自动化智能药房系统设计,上药控制系统部采用Clipper卡控制伺服电机,传送上药机械手至竖直平面运动X和Y方向的指定坐标位置,由上药机械手上的步进电机和旋转电磁铁推动药品进入指定储位.     

基于MEMS的角位置无线随动控制系统设计

角位置随动控制系统在数控机床、火炮自动控制中有重要应用,目前多采用自整角机实现.在布线困难的特殊场合下,有必要采用无线的方式实现对远端机械结构随动控制.设计了一个无线随动控制系统,并对系统的抗干扰性和跟随精度问题进行了实验研究.利用ARM微控制器对MEMS陀螺仪和加速度计获取的动态角位置信号进行自适应互补滤波处理,对nRF24L01无线传输模块进行跳频编程,进一步提高了系统的抗干扰性.此外,利用直流伺服电机驱动跟随机构,通过加装无线视频模块实现了远程可视化遥控.实验结果表明:设计的角位置无线随动系统运行稳定,角位置跟随误差小于0.3°,随动响应时间小于15 ms,无线随动距离500 m(通视).     

盘存储器中音圈电机的温度特性研究

现代硬盘机和光盘机的定位系统执行机构一般采用音圈电机驱动。定位系统的工作性能与音圈电机的性能密切相关。音圈电机的力矩常数是反映音圈电机性能的主要结构参数，它的温度特性对系统的伺服控制有较大的影响。本文测量了音圈电机力矩常数随温度的变化关系，该测量结果对研究音圈电机伺服控制的温度补偿具有重要意义。     

基于DSP的斜轴式望远镜机架控制系统设计

为了抑制望远镜驱动系统中的非线性干扰,设计了一种新型机架伺服控制系统;系统以45度斜轴机架转台为硬件平台,以DSP为主控制器,采用HQ7620摄像头模块进行位置反馈;首先DSP对图像模块采集的图像进行实时处理,得到目标图像质心的位置,并计算出该位置相对于视场中心的误差,接着对误差进行粒子群模糊PID控制,最后DSP的EV模块产生相应的PWM对机架驱动电机进行控制,实现对机架的高精度闭环控制;PWM波的频率设为10kHz;实验数据表明:与模糊PID控制和PID控制相比,系统粒子群模糊PID控制下水平与竖直方向的误差均值为0.323 2像素,大幅度地提高了控制的稳定性,满足实际要求。     

音圈电机温度特性的实验研究

现代硬盘机和光盘机的定位系统执行机构一般采用音圈电机驱动。定位系统的工作性与音圈电机的性能密切相关。文中测量了音圈电机力矩常了随温度的变化关系，该测量结果对研究音圈电机伺服控制的温度补偿具有重要意义。     

固定双桨驱动的无人水面艇自主直线路径跟踪系统

针对直流电机驱动固定双桨的无人水面艇,介绍了一种自主直线路径跟踪系统,该系统由岸基监控系统和艇载控制系统组成,具有自主航行和遥控航行两种工作模式,可在自主航行出现危险时切换到遥控模式,保证航行安全。岸基监控系统通过数传电台与艇载控制系统通信,向艇载控制系统发送控制命令,接收并显示其传回的状态信息;艇载控制系统以工控机为主控单元,进行数据采集与解算,与岸基监控系统通信,并为直线路径跟踪控制算法提供程序接口;GPS双天线高精度测向定位系统为直线路径跟踪控制算法提供位置和航向信息,直线路径跟踪控制算法根据距离偏差和航向偏差计算出左右两侧电机电压,进而控制无人水面艇航行。实验分别采用了PID、模糊控制和模糊PID三种控制方法,系统实际水上实验表明,在风力2~3级,晴到多云天气条件下,无人水面艇对目标路径的最大跟踪误差小于0.6 m。     

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。