机器视觉表面缺陷检测综述

目的 工业产品的表面缺陷对产品的美观度、舒适度和使用性能等带来不良影响,所以生产企业对产品的表面缺陷进行检测以便及时发现并加以控制。机器视觉的检测方法可以很大程度上克服人工检测方法的抽检率低、准确性不高、实时性差、效率低、劳动强度大等弊端,在现代工业中得到越来越广泛的研究和应用。方法 以机器视觉表面缺陷检测为研究对象,在广泛调研相关文献和发展成果的基础上,对基于机器视觉在表面缺陷检测领域的应用进行了综述。分析了典型机器视觉表面缺陷检测系统的工作原理和基本结构,阐述了表面缺陷视觉检测的研究现状、现有视觉软件和硬件平台,综述了机器视觉检测所涉及到的图像预处理算法、图像分割算法、图像特征提取及其选择算法、图像识别等相关理论和算法研究,并对每种主要方法的基本思想、特点和存在的局限性进行了总结,对未来可能的发展方向进行展望。结果 机器视觉表面缺陷检测系统中,图像处理和分析算法是重要内容,算法各有优缺点和其适应范围。如何提高算法的准确性、实时性和鲁棒性,一直是研究者们努力的方向。结论 机器视觉是对人类视觉的模拟,机器视觉表面检测涉及众多学科和理论,如何使检测进一步向自动化和智能化方向发展,还需要更深入的研究。     

基于智能视觉系统的饮料瓶封装缺陷检测技术

本文介绍了一种基于智能机器视觉系统的饮料瓶封装缺陷检测应用技术。根据饮料瓶封装缺陷检测的特点及实际生产要求,提出了一套应用智能机器视觉系统的总体解决方案。作者对整个系统的结构原理,工作流程以及各个组成部分的功能做了具体的阐述。应用结果表明,上述机器视觉系统实现方便,功能强大,应用效果良好。     

基于智能视觉系统的饮料瓶缺陷检测技术

研究基于智能机器视觉系统的饮料瓶封装缺陷检测应用技术。根据饮料瓶封装缺陷检测的特点及实际生产要求,提出了一套智能机器视觉系统应用的总体解决方案。对整个系统的结构原理,工作流程以及得个组成部分的功能做了具体的阐述。应用结果表明,使用上述机器视觉系统实现方便,功能强大,取得了良好的应用效果。     

一种基于智能机器视觉识别的工业探伤技术

磁粉探伤广泛应用于铁磁性工件表面和近表面缺陷检测,但目前的缺陷识别仍依赖于人工判断。为实现检测自动化,将机器视觉技术应用于缺陷识别,提出一种智能的螺栓缺陷在线检测系统,针对螺栓在生产过程中产生的纵向、横向裂纹,使用基于统计的磁痕裂纹识别方法和基于改进LBP特征和SVM分类器识别方法进行级联完成螺栓零件表面裂纹的自动识别。实验结果表明,该方法与传统的识别方法对比具有很好的分类识别效果,漏检率减少5%,同时能够满足实时性的需求。     

气囊封条贴片缺陷检测系统设计

针对汽车气囊封条贴片表面缺陷检测效率低下的弊端,构建了一种基于视觉软件HALCON可对气囊封条贴片进行自动化检测的机器视觉系统。运用图像处理算法中形态学算子实现对封条表面0. 3 mm2以上的污渍、露白、残缺的检测。通过对1 000个样本的检测与分析,系统的正确率超过99%,误报率小于1%,漏报率为0,结果表明:设计的系统具有精度高、稳定性强的优点。     

表面缺陷检测综述

基于机器视觉的表面缺陷检测技术已经广泛地应用在视觉检测各个领域中,它是确保自动化生产中产品质量的一个非常重要的环节。然而表面缺陷检测技术仍然面临着缺陷和非缺陷区域之间的低对比度,噪音和细微缺陷的相似性,检测速度慢和识别精度低等难题。为此,给出了近年来表面缺陷检测技术的最新进展。将表面检测技术分为3类：统计法、频谱法和模型法。对几种典型的表面缺陷检测技术进行了深入比较,包括特征提取、识别算法和算法性能,并分析了方法有效性的原因。最后,总结了表面缺陷检测技术面临的挑战和未来的发展趋势。     

基于并行演化计算的图像特征提取研究

图像特征提取已成为困扰智能化视觉信息处理的瓶颈。为了解决复杂背景下钢板表面缺陷的机器视觉检测问题,缩短视觉系统的开发周期,提高其实用性,在并行计算环境和视频仿真平台的基础上,探索机器视觉可塑性及形成机制,提出了将并行计算、视频仿真、演化计算相互融合解决钢板表面缺陷特征提取问题的方法,实现了演化计算与并行层次处理的特征选择、特征提取方法,为智能化的视觉信息处理开辟新的思路。实验证明,改进方案不仅具有可行性,而且能提高缺陷检测的准确性、实时性。     

基于机器视觉的汽车精密零件表面缺陷自动检测方法

汽车精密零件表面缺陷会导致零件故障,为了提高缺陷检测能力,提出基于机器视觉的汽车精密零件表面缺陷自动检测方法。构建汽车精密零件表面缺陷的机器视觉图像采集模型,采用单背景约束下的表面光泽点提取的方法,分析汽车精密零件表面的结构纹理特征值,在视觉传感下通过对汽车精密零件的形变、相变参数分析,分析汽车精密零件的机械性能和服役性能,在切削载荷作用下,通过疲劳裂纹的视觉特征重构,在机器视觉下采用表面残余应力及变质层的动态特征分析,通过缺陷特征检测和有限元仿真分析,实现对汽车精密零件表面缺陷自动检测。测试结果表明,采用该方法进行汽车精密零件表面缺陷检测的纹理匹配度较高,检测性能较好,对零件表面的断屑、化学磨损等各类缺陷检测的可靠性较高。     

基于机器视觉的塑料制品表面缺陷检测研究

设计了一套塑料制品表面缺陷检测的机器视觉系统,用于检测塑料制品表面划痕,凹坑和凸点这几类常见缺陷。机器视觉系统由硬件系统和软件系统构成。根据研究对象的特征,对塑料制品表面缺陷检测所需的硬件和系统进行选型,分析所选硬件及软件的特点,来获取更加清晰的表面图像信息。利用Halcon平台设计检测算法,结合塑料制品表面的特征,设计一套用于检测塑料制品表面缺陷的算法。构建高斯滤波器来对图像信息进行预处理,使用全局固定阈值分割图像,使用特征直方图来查看特征,根据特征进行选择轮廓并提取目标,并在图像上显示出缺陷区域及数量。     

基于机器视觉的钢卷尺表面缺陷检测系统设计

针对钢卷尺生产过程中表面缺陷检测效率低下的问题,构建一套应用于实际工业环境下的基于机器视觉的钢卷尺表面缺陷在线检测系统。首先,设计一种实验检测平台用于获取钢卷尺表面的图像;然后,通过图像分割的数字图像处理手段准确定位钢卷尺区域轮廓;最后,采用基于灰度值的模板匹配算法、边缘检测算法及颜色聚类方法对预处理后的图像进行匹配和特征计算,实现对目标物体和区域图像的快速定位和特征提取。结果表明：该检测系统的正确率达95.83%,平均检测速度达5.025 秒/根,基本代替了人工检测,为钢卷尺表面检测提供了一种检查正确率和效率较高的新方法。     

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。     

How do children do mathematics with LOGO?

Abstract  This paper considers some results of a study designed to investigate the kinds of mathematical activity undertaken by children (aged between 8 and 11) as they learned to program in LOGO. A model of learning modes is proposed, which attempts to describe the ways in which children used and acquired understanding of the programming/mathematical concepts involved. The remainder of the paper is concerned with discussing the validity and limitations of the model, and its implications for further research and curriculum development.