集成电路芯片引脚外观自动检测系统的研究

基于集成电路芯片引脚外观检测的需要,开发了自动检测系统.介绍了系统的组成、硬件结构、软件流程.该系统由芯片自动输送线、芯片拾取吸臂、机器视觉系统、良品与不良品分选臂、良品补给装置等组成,由工控机通过PLC控制技术,实现芯片上料、输送、外观检测、分选、卸料等的全自动化.该系统可检测芯片引脚在空间的11个尺寸参数,具有检测精度高、产品更换快速、操作简便等优点,适用于QFP封装集成电路芯片引脚外观的自动检测,可显著提高生产效率及产品质量.     

VCM磁钢自动检测系统的光学系统设计

为VCM磁钢自动检测系统设计了一套高精度的光学系统。该光学系统分为成像系统和照明系统两部分,利用远心光路方式对成像系统进行了设计。通过光学计算,给出了焦距为16mm,相对孔径为1：2．5,视场角为120°的成像系统设计参数。所试制的样机经过实验表明镜头成像清晰,性能可靠,满足测量精度要求。     

A new denoising algorithm for MFL data obtained from seamless pipeline inspection

The magnetic flux leakage (MFL) nondestructive evaluation technique is used extensively for in-service inspection of gas and oil pipelines. Unfortunately, the MFL data obtained from seamless pipeline inspection is usually contaminated by various sources of noise, which considerably reduces the detectability of defect signals in MFL data. In this paper, a new denoising algorithm is presented for removing seamless pipe noise (SPN) and system noise contained in MFL data. The algorithm first utilizes the new wavelet domain adaptive filtering method proposed by combining wavelet transform with the adaptive filtering technique to remove SPN contained in MFL data and then exploits the coefficient denoising approach with wavelet transform to cancel the system noise in the output of the wavelet domain adaptive SPN cancellation system. Theoretical analysis shows that the proposed denoising algorithm has a better overall performance than the existing denoising algorithm. Results of application of the proposed algorithm to MFL data from field tests are presented to demonstrate the performance of the proposed algorithm compared with the existing denoising algorithm. The text was submitted by the author in English.     

集成电路芯片管脚尺寸自动检测系统的状态分析

机器视觉自动检测系统的稳定性将直接影响产品检测的质量。本文根据随机过程的理论,利 用SAS软件对研究开发的集成用路芯片管脚尺寸检测系统的工作状态进行了分析测试。测试 结果表明,整个系统的测量结果是一个具有各态历经性的平稳随机过程,因此,我们利用一段 样本值就能估计整个过程的均值和标准差,从而获得整个过程的性质。     

激光测距系统整形模块和低通滤波模块优化设计

由于减小相位式激光测距系统的鉴相误差可提高测距精度,本文对鉴相器前置整形模块和后置滤波模块进行了优化设计,以提高鉴相精度.针对整形模块,引入了迟滞比较器,克服了传统开环比较电路在实际噪声条件下存在的多重触发缺陷,解决了鉴相器输出方波高电平宽度不稳定的问题.针对滤波模块,介绍了基于MC4044鉴相芯片的两种典型放大/滤波电路及其缺陷,使用FilterPro软件设计了4阶有源低通滤波器,并说明了它相对于典型设计的优势.实验结果表明:相比于开环比较器,本文设计的迟滞比较器避免了接地(GND)噪声引起的多重跳变现象,输出方波的上升沿时问由1.66μs下降为108 ns;与基于MC4044的两种典型放大/滤波模块设计相比,本文设计的低通滤波电路克服了输出DC电平值非线性变化的缺陷线性度(R2)值由0.908 3提高至0.999 9)和灵敏度较低的缺陷(转化增益常量提高了96.5％),而输出DC电平上的干扰信号峰峰值则由50～230 mV下降至10～ 20 mV,有效减少了后级的A/D采样误差,提高了鉴相精度.     

一种基于非线性滤波算法的厚膜电路视觉检测系统的实现

在厚膜电路生产中需要利用人工通过显微镜对基片上电路的短路、断路的质量问题进行识别,笔者在一个厚膜电路视觉质量检测设备的开发项目中提出了利用非线性滤波算法以及膨胀、腐蚀、细化等图像形态处理的方法得到被测电路的骨骼化图像,然后通过统计线路和基片骨骼化图像的连接分量的数量判断电路的短路和断路问题,该方案在实际中使用良好,大大提高了厚膜电路的检测效率与产品质量。     

轴承滚子磁痕探伤分析

依据国家标准,采用磁粉探伤的方法对滚子的表面缺陷进行检查,并采用金相法分析,从宏观和微观两方面确定磁痕产生的原因。结果显示,带状碳化物超标是引起磁粉堆积形成磁痕的原因。     

A method for magnetic inspection of layered structures

A three-layer structure is studied with a computer model. The magnetization of any layer was shown to be determined by both its magnetic properties (the basic magnetization curve) and the magnetic properties of the other layers and core. The informative (secondary) magnetic field at any point of space was found to contain complete information on the parameters of each layer. A new procedure allowing the information to be available is suggested. On this basis, a method for the magnetic inspection of layered structures is developed.     

汽轮机动叶片磁粉探伤伪磁痕现象分析

对汽轮机动叶片磁粉探伤过程中出现的特殊磁痕现象进行了分析,找出了产生伪磁痕的原因,通过热处理工艺消除了特殊磁痕现象。     

一种磁保持继电器驱动电路的设计

磁保持继电器是一种能耗低、稳定可靠的双稳态继电器,采用脉冲驱动。本文介绍了一种通用的驱动电路,中央控制单元输出的两路信号触发IR2110组成的驱动电路,驱动电路控制由MOSFET搭接的H桥主电路,实现磁保持继电器在两个稳态之间相互切换。总体结构简单、通用,工作可靠。     

An automated inspection system for stents

In this paper, the automated inspection of stent manufacturing is presented. It was developed and applied to acquire, process, and analyze the image data of stents using a line-scan camera and automated multi-axes scan mechanics to acquire the image data during the scanning process. A stent is a wire-metal-mesh tube used to prop open an artery during angioplasty. The stent is collapsed to a small diameter and put over a balloon catheter. It is then moved into the area of the blockage to restore normal blood flow and keep an artery open. A cardiovascular stent has hundreds of critical features with tight tolerances. They must be 100% inspected for dimensional conformity, and also for visual defects. The designed automated stent-inspection system utilizes a high-resolution line-scan camera to generate a flat, unrolled view of the stent, and was developed by Carinthian Tech Research CTR-AG. A novel approach is proposed for automatic error detection in stents. Image-processing-based algorithms are applied and work is under way for producing fully automated algorithms. The system generates a large, highly detailed image of the entire stent pattern in a few seconds (typically 20 s and the error detection in 10 to 15 s). Manufacturers of stents can benefit greatly from this new technology, which suits the particular inspection needs of the 100% quality requirement of stent production. The technology continues to evolve and take advantage of the latest developments in the growing field of digital optics, imaging, and computer capabilities.     

Development of a miniature permanent magnetic circuit for nuclear magnetic resonance chip

The existing researches of miniature magnetic circuits focus on the single-sided permanent magnetic circuits and the Halbach permanent magnetic circuits. In the single-sided permanent magnetic circuits, the magnetic flux density is always very low in the work region. In the Halbach permanent magnetic circuits, there are always great difficulties in the manufacturing and assembly process. The static magnetic flux density required for nuclear magnetic resonance(NMR) chip is analyzed based on the signal noise ratio(SNR) calculation model, and then a miniature C-shaped permanent magnetic circuit is designed as the required magnetic flux density. Based on Kirchhoff’s law and magnetic flux refraction principle, the concept of a single shimming ring is proposed to improve the performance of the designed magnetic circuit. Using the finite element method, a comparative calculation is conducted. The calculation results demonstrate that the magnetic circuit improved with a single shimming has higher magnetic flux density and better magnetic field homogeneity than the one improved with no shimming ring or double shimming rings. The proposed magnetic circuit is manufactured and its experimental test platform is also built. The magnetic flux density measured in the work region is 0.7 T, which is well coincided with the theoretical design. The spatial variation of the magnetic field is within the range of the instrument error. At last, the temperature dependence of the magnetic flux density produced by the proposed magnetic circuit is investigated through both theoretical analysis and experimental study, and a linear functional model is obtained. The proposed research is crucial for solving the problem in the application of NMR-chip under different environmental temperatures.     

Automated inspection system for headlamp reflectors

Up to now the quality control of headlamp reflectors for vehicles has been visually made by inspectors (100%-control). The results depend on the daily constitution and attention of the inspectors. In many cases, those “human factors” lead to dissatisfactory quality control and rejects due to assumed defects. To avoid this and to accordingly reduce production costs and save the environment, a manufacturer of image processing systems and the three biggest manufacturers of car reflectors in Europe have initiated a project with the intention of solving the current problems. This article gives an overview of the project under the aspect of the economical automation of the whole process of the car reflector inspection. The project began in May 2002 and finished in December 2004 and was supported by the European Commission under the 5th framework competitive and sustainable growth, FINDER, project no. G6RD-CT-2002-00668 [EC-research-program, 2001, Fast intelligent defect recognition system (FINDER)]. The work described in this paper is a summary of the technical reports from the authors made for this project [4–8].     

宽幅胶片弊病在线检测系统

本文介绍了一套用于宽幅胶片生产线整理工序的弊病在线检测系统，该系统用来实时检测胶片表面常见的弊病。系统采用2台线阵CCD摄像机同步成像，940nm的LED面阵光源提供照明，利用单行处理、多行判断的快速弊病检测算法及时发现弊病。现场运行结果表明，系统能够完成对运行速度为90m／min，宽幅为1300mm的胶片表面弊病的检测任务。     

磁悬浮轴承结构与磁路分析

从受控自由度数、磁力产生方式、磁极结构形式、控制电流性质等方面对磁悬浮轴承进行了分类与比较.针对各种典型磁悬浮轴承给出了其结构与磁路示意图,并进行了定性分析与比较,最后分析了磁悬浮轴承结构与磁路方面研究与发展方向.     

Automatic optical inspection for detecting defects on printed circuit board inner layers

This paper studies automatic optical inspection for detecting defects on the printed circuit board inner layer. The development of this study can be divided into five stages, they are reference image rebuilding, inspection image normalization, image subtraction, defects separation and defect classification. In the image subtraction stage, the difference between the reference image from the printed circuit board design and the inspected image is checked for defects. Each defect region is separated using a defect outer boundary tracing method. A boundary state transition method is proposed to classify the defect types. This system can recognize eight defect types, open, mouse bite, pinhole, missing conductor, short, spur, excess copper and missing hole. In addition, a comparison with the methods described in the literature is made, proving that the proposed method produces better results .     

An automatic optical inspection system for inspection of CMOS compact camera module assembly

This paper presents the development of an automatic inspection system to check lens focus status and white balance level and to inspect defects including black and white defect, dim defect, color defect, and line defects in manufacturing process of compact camera module. To check the imaging status and inspect the defects of compact camera module, a unique image capturing system is developed to get image data from CMOS sensor at high speed. It has a complex programmable logic device, and the camera link and the frame grabber is used to transfer and store images to PC. Several kinds of unique image charts are designed to inspect the various types of defects in compact camera module, and they are implemented and displayed on the LCD monitor directly to reduce handling and exchanging time of inspection charts during test procedures. Various image processing algorithms are developed to analyze the captured image from each test chart and to find and verify the defects of camera modules. The experimental results show that the proposed system is able to reliably inspect various types of defects with high precision and high speed in real manufacturing condition.     

On-line 3-D system for the inspection of deformable parts

In spite of the development of automated tolerance inspection systems for manufactured parts over the years, there are still processes that inevitably require manual intervention making full automation impossible in most cases; in particular when dealing with deformable parts. In most current industrial inspection systems, a deformable part under inspection must first be mechanically constrained on a rigid support or jig so as to be able to compare it with its nominal shape. This paper presents a new system to perform real-time surface inspection of deformable parts that does not require fixturing. Instead, the proposed system applies virtual forces to the part??s CAD model as if the part was installed in the fixturing device. Normally, a precise finite element method (FEM) simulation should be used to approximate the deformation that appends when the part is installed in the device. Even with a fast parallel computer, FEM is far from being real-time and cannot be used for on-line inspection. In the proposed system, a radial basis function approximation of the FEM simulation is trained off-line and used to speed-up the simulation by an order of magnitude. Experimental evaluation of the proposed system is presented for three plastic parts. Using the proposed scheme, an approximation of 0.25?mm compared with the real deformation was obtained. In this paper, statistical results are presented such as the average deviation, standard deviation, and processing time between the approximations obtained with the proposed method and with the finite element method applied to the full CAD model.     

A hardware-software system for the magnetographic inspection of ferromagnetic objects

A hardware-software system, which incorporates a scanning unit of a standard magnetographic flaw detector attached to a personal computer and computer programs that allow one to obtain signal records and visualize defect fields that are recorded on a magnetic tape on the screen of a monitor, has been developed for magnetographic nondestructive testing.