图像FAST角点检测算法的FPGA实现与系统集成

基于Vivado HLS工具封装了包括FAST算法和AXI接口的FPGA硬件IP,并将该IP集成到工业摄像机的嵌入式系统中,工作摄像机中FAST算法的最终处理结果传输给视觉检测设备主机.利用相同图像的FAST角点检测算法对FPGA算法电路和OpenCV算法程序进行对比实验,完成相同功能的情况下前者的处理速度比后者快约6...     

Inspection allocation in manufacturing systems using stochasticsearch techniques

Quality is the hallmark of a competitive product. It is necessary to use inspection stations to check product quality and process performance. In this paper, the authors are concerned with the problem of location of inspection stations in a multistage manufacturing system. The authors present two stochastic search algorithms for solving this problem, one based on simulated annealing and the other on genetic algorithms. These algorithms are developed to determine the location of inspection stations resulting in a minimum expected total cost in a multistage manufacturing system. The total cost includes inspection, processing and scrapping cost at each stage of the production process. A penalty cost is also included in it to account for a defective item which is not detected by the inspection scheme. A set of test examples are solved using these algorithms. The authors also compare performance of these two algorithms     

Visual change detection on tunnel linings

We describe an automated system for detecting, localising, clustering and ranking visual changes on tunnel surfaces. The system is designed to provide assistance to expert human inspectors carrying out structural health monitoring and maintenance on ageing tunnel networks. A three-dimensional tunnel surface model is first recovered from a set of reference images using Structure from Motion techniques. New images are localised accurately within the model and changes are detected versus the reference images and model geometry. We formulate the problem of detecting changes probabilistically and evaluate the use of different feature maps and a novel geometric prior to achieve invariance to noise and nuisance sources such as parallax and lighting changes. A clustering and ranking method is proposed which efficiently presents detected changes and further improves the inspection efficiency. System performance is assessed on a real data set collected using a low-cost prototype capture device and labelled with ground truth. Results demonstrate that our system is a step towards higher frequency visual inspection at a reduced cost.     

老旧建筑安全鉴定辅助决策系统的初步开发

以老旧建筑的表观检测数据或震害调查结果为依据,利用区间分析方法、模糊综合评判模型、专家系统的构造思想等最新信息处理技术建立起整套的老旧建筑安全鉴定辅助决策系统(专家系统).系统按照检测管理步骤(现场监测→数据处理→专家评价),分为数据录入及管理、等级评定、专家评价三大模块.该系统不但可以帮助建筑物管理者处理大量的检测数据,评价既有建筑物的安全等级,还可以根据老旧建筑物的实际情况,给出专家的最佳管理方案.     

Evaluation of a job‐aiding tool in inspection systems

Visual inspection plays a very important role in ensuring quality in the manufacturing and service industries. Two determinants of inspection performance are visual search and decision‐making. Improvement in any one of the components will have an impact on system performance. Job‐aids, accompanied by training, have proven to be effective in enhancing accuracy and reducing search time in visual inspection systems. This article aims to investigate the effects of search strategy along with task complexity and pacing on inspection performance using a job‐aiding tool. To facilitate the experiments, an enhanced job‐aiding tool in a simulated visual inspection environment was developed. This tool enables an inspector to track his or her search path in visual inspection systems. A pilot study and two experiments were conducted using this tool. The pilot study examined the effectiveness of the job‐aiding tool. The first experiment studied the effect of search strategy and task complexity on inspection system performance and the second experiment studied the impact of search strategy, task complexity, and pacing on system performance. Results from this research can be used to better design an inspection system. © 2007 Wiley Periodicals, Inc.     

Automatic inspection of mechanical parts using geometric models and laser range finder data

This paper addresses the problems associated in processing arrays of depth data in order to achieve the goal of automatic inspection of mechanical parts, i. e. developing general model-based inspection strategies that can be applied to a range of objects. The main problems in processing this data are segmenting out reliable primitives from the data and matching these primitives to those in a stored geometric model of an object. The ability of a 3D vision system to provide depth data accurate enough to perform automatic inspection tasks was until recently only possible at a short range from an object, typically a few centimetres. However it is now possible to produce dense data from a vision system situated further from the object, typically half a metre to a metre. Such a system is outlined. Some current model-based matching techniques are assessed for their suitability for employment in inspection type tasks. One approach is adopted and modifications that improve the efficiency and accuracy of the method for inspection purposes are presented. Finally, an inspection strategy is outlined and its performance assessed. Results are presented on both artificial and real depth data.     

激光拼焊焊缝跟踪系统视觉检测方法的研究

激光焊接作为一种新的焊接技术,其对焊缝跟踪提出很高的精度要求。本文针对焊缝跟踪系统中视觉检测单元的精度进行了深入分析,分别对跟踪系统视觉单元精度的定义,视觉检测精度控制的原理,图像的采集以及图像处理的方法做了研究,并提出了一种精确的直线焊缝跟踪视觉检测方法。     

Automatic Optical Inspection System with Telecentric Optics and Phase-measuring Profilometry for Highly Accurate Localization of Electronic Packages

Typical visual placement inspection systems in semiconductor or electronics manufacturing industries use only highly-magnified two-dimensional imaging with controlled illumination for high accuracy. However, current semiconductor packaging technology needs more precise manufacturing processes for highly integrated semiconductor packages, in which high-precision alignment between the semiconductor die and the matched substrate is indispensable for successful electronic interconnection. To solve this problem, an advanced visual placement inspection system for 3D stacking of electronic components is proposed; it utilizes 3D profilometry and 2D telecentric optics. In addition to the introduction of the proposed system, the system calibration algorithms and the information processing algorithms for accurate positioning of the semiconductor die, as well as the implemented inspection system are described in detail. To verify the system performance, a series of real experiments on newly developed flip-chip packages for high-performance computing were performed, and the results are analyzed and discussed.

     

基于 ADSP-2181 的 PCB标志定位系统

结合当前电子技术和图像处理技术的最新发展,设计了一种采用ADSP-2181数字信号处理器建构的图像检测定位的硬件平台,以满足图像检测的工业应用需要。运用并行数据流的分析方法系统论证了ADSP-2181作为图像检测系统核心处理器方案,提出了系统的数据流模型和控制模型,并以此设计实现了一个较高性能的硬件系统,具有视频图像获取、实时显示、图像处理和图像检测等多种功能。从PCB自动检测的标志识别及定位的需要出发,提出了适合硬件处理的Hough变换算法进行PCB圆形定位标志的检测,并给出了实验结果。     

数字扫频仪中的实时控制系统设计与研究

针对国内的扫频仪价格较贵、体积庞大和电路结构复杂等问题,提出了采用ARM9处理器S3C2440作为控制电路的核心,将其嵌入式系统解决方案引入到扫频仪当中.实时性是系统软件设计的关键,扫频仪中采用了实时操作系统μC/OS-Ⅱ.通过对任务切换时间、任务执行周期及CPU利用率的测试,对系统中各任务的可调度性、实时性和系统资源使用率进行了分析,提出了合理的任务划分及资源分配方案.整个系统的控制与数据处理均由单片S3C2440完成,简化了电路结构,降低了制作成本.     

基于虚拟仪器的产品标签视觉检测系统

针对生产过程中人工检测产品标签制约生产速度的情况,采用一种基于虚拟仪器的机器视觉产品标签检测系统,该系统以LabVIEW为平台,配以1394摄像头和图像采集卡,利用一定的图像处理技术,如平均滤波、平滑处理和局部增强处理等,完成视觉检测;经过测试,从图像采集到图像处理得出结论耗时不超过40ms,满足性能指标的要求,该系统开发周期短,检测速度快,充分发挥了虚拟仪器技术的功能强大、扩展性强的特点。     

机器视觉在印刷缺陷在线检测中的应用与研究

为了提高印刷缺陷检测准确性与效率,满足缺陷检测的实时性,提出了机器视觉技术应用于印刷缺陷在线检测并研究检测过程中的相关问题.设计印刷缺陷在线检测的方案及以数字信号处理器DSP为核心的视觉在线检测系统的硬件结构组成.研究图像预处理、图像匹配与缺陷检测的算法并加以改进使其满足缺陷检测的实时性.开发印刷品缺陷视觉检测软件,对缺陷检测流程进行仿真,验证检测方案与图像处理算法的可行性.     

A Robot Application for Marine Vessel Inspection

Seagoing vessels have to undergo regular inspections, which are currently performed manually by ship surveyors. The main cost factor in a ship inspection is to provide access to the different areas of the ship, since the surveyor has to be close to the inspected parts, usually within arm's reach, either to perform a visual analysis or to take thickness measurements. The access to the structural elements in cargo holds, e.g., bulkheads, is normally provided by staging or by “cherry‐picking” cranes. To make ship inspections safer and more cost‐efficient, we have introduced new inspection methods, tools, and systems, which have been evaluated in field trials, particularly focusing on cargo holds. More precisely, two magnetic climbing robots and a micro‐aerial vehicle, which are able to assist the surveyor during the inspection, are introduced. Since localization of inspection data is mandatory for the surveyor, we also introduce an external localization system that has been verified in field trials, using a climbing inspection robot. Furthermore, the inspection data collected by the robotic systems are organized and handled by a spatial content management system that enables us to compare the inspection data of one survey with those from another, as well as to document the ship inspection when the robot team is used. Image‐based defect detection is addressed by proposing an integrated solution for detecting corrosion and cracks. The systems' performance is reported, as well as conclusions on their usability, all in accordance with the output of field trials performed onboard two different vessels under real inspection conditions.     

Use of saccadic latency for visual inspection system

In some industrial inspection processes, multiprocess‐handling workers are required to enter the results of visual inspection tests without using their hands because of efficiency or hygiene reasons. We have developed a hands‐free visual inspection system by using saccadic latency, a temporal characteristic of saccadic eye movements. The proposed system is free from the Midas touch problem (i.e., the difficulty in developing an eye‐typing interface owing to the difficulty in differentiating between intentional blinks and gazes and natural ones). For verifying the system, an experiment was conducted in which ten subjects performed a visual inspection task. The average defect detection rates were 99.4%, and no Midas touch–related errors were observed. Results of the error analysis showed that redesigning the system interface would lead to a further enhancement of the system performance. © 2011 Wiley Periodicals, Inc.     

面向光学薄膜瑕疵检测的二值图像快速Blob分析算法

针对光学薄膜瑕疵检测应用中的高实时性图像处理要求,提出一种基于游程的二值图像快速Blob分析算法。采用步进式动态扫描方式,每个游程仅需扫描一次,且不必与相邻行的所有游程进行比较,算法的搜索空间得到压缩;游程连通性比较的分支少,简化了判断过程,提高了操作效率;所设计的游程及目标对象的数据结构允许由任一游程节点快速访问其所属链表的首部和尾部,不仅为后续的数据访问提供了便利,且提高了标记冲突时链表合并的操作速度,避免了冲突等价表的介入。实验结果表明该算法具有鲁棒、高效的特性,并已在光学薄膜瑕疵检测系统中得到了应用。     

用于白车身检测的测量控制系统设计

为实现白车身在线检测站中测量设备的统一管理与远程通信,提高测量系统的工作效率,设计了一种用于白车身检测的测量控制系统。采用STM32F407芯片为核心并移植μC/OS-Ⅱ和LwIP,并搭建Web Server实现远程通信;建立了多线程任务,实现串口、网口和USB之间的信息交互;分析了数据路由转发过程中存在的数据安全性问题,就通信过程中丢包现象展开讨论,并提出解决方案;采用二维归一化灰度互相关法处理图像的二维定位,提高了处理速度。实验结果表明,该系统能够提供远程通信功能,降低成本,且提高了设备管理的效率。     

Multipurpose inspection task simulator

Experimentation using a computer simulation of a system has many advantages over more traditional techniques. In this project, computer graphics are used to create an inspection task simulator. The simulator allows for easy manipulation of variables known to affect inspection performance, quick construction of visual stimuli, a choice of randomly generated or intentionally input faults on the stimuli, controlled % defective, feedback options and automatic collection of inspection data. The inspection task simulator has possible applications in experimentation, training and selection of inspectors.     

Automated thermal fuse inspection using machine vision and artificial neural networks

Machine vision is an excellent tool for inspecting a variety of items such as textiles, fruit, printed circuit boards, electrical components, labels, integrated circuits, machine tools, etc. This paper presents an intelligent system that incorporates machine vision with artificial intelligent networks to automatically inspect thermal fuses. An effective inspection flow is proposed to detect four commonly seen defects, including black-dot, small-head, bur, and flake during the production of thermal fuses. Backpropagation neural networks and learning vector quantization performance is compared in detecting the bur defect because of its illegibility. Different numbers of defective samples were screened out from a production line in a case study company and used to demonstrate the efficacy of the proposed system. Currently, the proposed inspection system is operating at the case study company, replacing four to six human inspectors. The system not only ensures the quality of the thermal fuses produced, but also reduced the cost of manual visual inspection.     

基于LabVIEW的网络机器视觉检测系统

针对生产过程中需要实时监测零件尺寸的情况,采用一种网络机器视觉尺寸测量系统,该系统以LabVIEW为平台,配以1394摄像头和图像采集卡,利用一定的图像处理技术完成视觉检测,利用DataSocket技术实现图像的网络实时发布和客户端图像的接收。经过测试,从图像采集、处理和发布系统耗时不超过280m s,该系统开发周期短,检测速度快,充分发挥了虚拟仪器技术的功能强大、扩展性强的特点。     

基于数据仓库的房地产税收预警系统的设计与实现

基于房地产行业成本数据模型,结合已有的房地产涉税信息,建立了房地产税收预警系统的数据仓库。预警系统对各个房地产项目根据一定业务规则进行分析比对,自动归集涉税风险信息。实践证明该预警系统可以有效提高税务检查绩效,是深化数据分析应用的成功尝试。