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提出一种利用标准球对显微图像测量系统进行标定的方法.该方法利用显微系统小视场小景深的成像特点简化计算模型,减少标定参数.通过标准球图像在水平和垂直方向上的直径比计算比例因子;利用标准球边缘图像的边缘点集.运用优化的方法来计算成像系统的畸变系数和主点位置.系统的放大倍数由标准球的实际直径来标定得出.利用标准球在多摄像机公共视场内其轮廓在任何位置均可见这一特性,可同时对显微图像测量系统中的多个摄像机进行标定,简化标定过程.实验结果表明,该方法标定精度较高,标定后的测量系统的极限误差3σ为2.4μm. 相似文献
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目的在视觉测量领域,摄像机的标定精度是最终测量精确度的决定性因素,为了提高标定板特征的提取精度,提出一种基于亚像素边缘的提取方法。方法针对圆点标定板,首先采集标定板图像,对图像进行处理,获取像素级别边缘,然后以边缘像素点为中心,取3×3的数字窗口计算梯度方向,在梯度方向上进行像素点灰度的双曲正切拟合,获取亚像素级别边缘,最后对亚像素边缘按照圆形进行拟合,求得圆心坐标。结果实验表明算法的分辨率达到0.03个像素,精度可达0.1个像素。结论该算法具有稳定可靠,精度高,运算速度快等特点,能够应用于图像拼接和分割,特征提取和摄像机标定等领域。 相似文献
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本论文提出了一种基于图像边缘特征的零件分类与定位算法。算法首先对图像腐蚀膨胀等预处理,然后通过边缘检测得零件的完整边缘轮廓,然后对零件边缘轮廓图像使用方向梯度直方图(HOG)构造训练数据,并采用支持向量机(SVM)在训练数据上训练分类识别模型,最后进行检测。根据检测结果获得图像中零件的种类和位置信息,然后使用棋盘格标定的方法来确定深度。标定时,取标定板上的两个点来计算深度,根据已知的深度,获取实际抓取点的两个图像坐标系的x,y值,计算世界坐标系坐标。此系统能解决零件分类、定位问题,能广泛运用于生产线引导工业机器人进行零件抓取。 相似文献
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一种基于MATLAB的植物叶片参数测量系统 总被引:2,自引:0,他引:2
提出了一种基于MATLAB的植物叶片参数自动测量系统方案.该系统利用扫描仪获取包含标定物的叶片图像,对其二值化后进行边缘跟踪,获得标定物和叶片的边界,最后借助标定物的实际直径和面积得到叶片的面积、周长、长、宽等参数.经对两种叶片进行的实验.结果表明,此系统能够快速、准确地进行叶片参数的自动测量,具有较高的效率和实用性. 相似文献
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为了实现对近景目标物的三维测量,研制了一种小型仿生复眼系统。介绍了该复眼系统的结构及其参数设计原则,并对该系统采用的标定、三维测量等算法进行研究。首先根据复眼成像特点搭建了标定和测量平台,并分别使用张正友的方法、直接线性变换法、Tsai式两步法三种摄像机标定方法对复眼的中心子眼进行标定,通过比较实验结果发现Tsai式标定方法精度更高,更适用于本复眼系统的标定。然后针对边缘子眼光轴与图像传感器不垂直问题,提出了一种新的图像畸变数学模型,有效的提高了边缘子眼的标定精度。最后建立了多子眼三维探测模型,并探索了多子眼成像对复眼相机测量精度的影响,认为三子眼可获得比双子眼更高的精度和稳定性。实验结果表明,在距离复眼相机150?260 mm范围内,该复眼探测系统的三维测量相对误差在2%左右,在满足仪器小型化的同时能基本实现近景三维测量。 相似文献
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针对螺纹几何参数测量过程中,传统人工测量效率低、仪器昂贵、耗时费力、偶伴有人为误差等不足.本研究采用非接触测量的方法,利用计算机视觉的图像处理技术,通过系统标定、图像采集、图像预处理、边缘检测、几何参数计算等步骤,实现了对螺纹几何参数的自动测量.通过大量实验证明,该系统具有快捷高效、数据可靠、易于操作、替代传统人工操作... 相似文献
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目的针对EAN-13商品条码,运用机器视觉技术进行商品条码质量检测,实现一体化、自动化、智能化检验。方法根据检测要求,设计商品条码图像采集装置,通过系统标定完成初始化。条码检测时,采集待测条码图像,进行畸变矫正;通过边缘检测、形态处理和轮廓匹配,找到条码准确位置,分割出条码图像区域,对其旋转校正,分为条码区域和数字区域;对条码区域,水平采样获取反射曲线,计算光学特性参数和译码数据,通过几何特征分析,结合标定参数,计算出相关结构参数;对数字区域,通过字符分割、模版匹配,完成字符识别;最后,通过比对分析,获取全部检测数据。结果分别采用该方法和传统方法,对100个EAN-13条码样本进行了检测对比,试验表明该方法的检验结果符合国家标准,检测数据准确可靠;该方法操作快捷,精度更高,检测速度大幅提高。结论文中方法实现了商品条码质量检测的一体化、自动化、智能化处理,显著提高了检验水平和工作效率。 相似文献
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麻程健;史飞;王昊利 《中国计量学院学报》2013,(4):340-346
针对微小复杂产品表面形貌、几何特征、关键点等综合测量的要求,提出了基于立体显微图像的三维微尺度测量方法.利用立体显微镜及两台数字相机获得被测对象两个不同观测角度的显微图像,通过图像处理技术和几何原理计算得到被测对象的空间三维信息,最终实现三维微尺度测量.为了验证所提出方法的有效性,以具有一定倾角的显微标定板为测量对象,在图像采集、滤波、二值化、边缘检测以及形心计算的基础上进行显微系统的标定,分别对左右各10个相同角度进行了实测.结果是相对误差均在3%以内,说明该测量方法可以获得较高的测量精度. 相似文献
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Steffen Müller-Probandt 《材料科学与工程:中英文B版...》2018,(4):161-177
We associate a variety of innovations with the term "Industry 4.0". The pioneer of many 4.0 modifications forms the basisfor the trend towards the integrated di... 相似文献
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Janet Lang 《Materials and Manufacturing Processes》2017,32(7-8):857-866
ABSTRACTThe production of ferrous metal increased during the Roman Late Republican period, Principate and Empire. The direct bloomery process was used to extract the metal from its ores using slag-tapping and slag-pit furnaces. The fuel was charcoal and an air blast was introduced by bellows-operated tuyères. Iron formed as a bloom, often as a spongy mass of metal, which contained impurities from the smelting process, including unreacted ore, fuel, slag and fragments from the furnace walls, while the metal was often inhomogeneous with varied carbon contents. Blooms were either smithed directly into bars or ingots or they were broken up, which also allowed the removal of gross impurities and a selection of pieces with similar properties to be made. These could then be forge-welded together and formed into characteristically shaped ingots. Making steel in the furnace seems to have been achieved: it depended on the ore and the furnace and conditions within it. Surface carburization was also carried out. Iron and steel were used extensively in construction and for tools and weapons. Fire welding was often used to add pieces of steel to make the edges of tools and weapons, which could be heat-treated by quenching to harden them. 相似文献
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A four-ball tester was used to evaluate the anti-wear performance of three kinds of organomolybdemun compounds in the engine oils, i. e., molybdenum dialkyldithiophosphate (MoDDP), molybdenum dialkyldithiocarbamate ( MoDTC), and sulphur and phosphorus freeorganomolybdeum (Molybdate). The results indicate that a low concentration of MoDDP doesn' t improve the anti-wear properties of the commercial engine oils, but a high concentration of MoDDP can obviously improve the anti-wear properties and the load-carrying capacity of the engine oils. MoDTC doesn' t improve the antiwear properties of the engine oils, but worsens the anti-wear properties of the oils. Signifi can timprove ment of frictional and wear characteristics is obtained with Molybdate added in the commercial engine oils and the formulated oils. 相似文献
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Standards are the basis for production enterprises to organize production ex-factory inspection trade 《中国标准化(英文版)》2008,25(1):24-25
Standards are the basis for production enterprises to organize production, ex-factory inspection, trade (delivery) and technical exchanges, product certification, quality arbitration and supervision.…… 相似文献
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S. K. Malhotra Paramanand Singh A. Thirunavukkarasu 《Materials and Manufacturing Processes》2006,21(7):652-657
Al2O3-ZrO2 nanocomposites were developed starting with the solgel process. Composite alumina-zirconia nanopowders were synthesized from metallorganic precursors (Aluminium secondary butoxide and zirconium Iso propoxide) using the solgel process. The parameters affecting the synthesis—solvent, concentration of precursor, R/H ratio (i.e., dilution of water in solvent)—were varied as also the temperature and pH. BET and TEM were used to measure nanosize. Diffuse reflectance spectroscopy and also qualitative optical absorption led to identical particle size estimate. The variation of process parameters was used to study the effect and interdependence of process parameters. Artificial Neural Networks was used to rigorously analyze the process. Although this led to confirmation of interdependence of parameters, the presence of a single overwhelming solvent variable was also established. Then the optimal process was used to synthesize more nanopowder. To produce bulk nanocomposite the nanopowders were sintered by varying the temperature and time period. The sintered lithoids were probed with a vickers hardness tester to measure elastic modulus, hardness, and fracture toughness. The results showed high elastic modulus, modest hardness, and very high fracture toughness. 相似文献
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Friction Stir Processing Strategies for Uniform Distribution of Reinforcement in a Surface Composite
Vipin Sharma Yashpal Gupta Ujjwal Prakash 《Materials and Manufacturing Processes》2016,31(10):1384-1392
Friction stir processing (FSP) is an important technique for preparing surface composites. Fabricating defect-free surface composites with uniform particle distribution by FSP is a challenging task. In this study, silicon carbide particles reinforced AA5083 alloy surface composites was fabricated using different FSP strategies including variation in process parameters, dual-tool processing and tool offset overlapping. Material flow of the processed material with reinforcement particles demonstrated that the distribution of particles was influenced by the stirring action of the probe as well as the extrusion of the plasticized material due to the movement of the tool. Process parameters, particularly rotational speed, showed a dominant influence on the distribution of silicon carbide particles. 相似文献
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Zusammenfassung Bei der Gestaltung von Ernteprozessen — beispielsweise des Prozesses Mähdrusch, Körnertransport und -abnahme — als transportverbundene Fließarbeitsverfahren mit mindestens zwei verschiedenen Arbeitsmitteln gibt es einen großen Optimierungsspielraum. Solche Prozesse sind mehrstufige Bedienungsprozesse mit gemischter Anordnung der Bedienungseinrichtungen. Außerdem besitzen sie stark ausgeprägte räumliche Aspekte. Es wird vor allem gezeigt, welche Merkmale solcher Prozesse in Simulationsmodellen abgebildet sein müssen, welche Zielgrößen in Abhängigkeit von welchen Einflußgrößen unter Berücksichtigung welcher Prozeßbedingungen ermittelt werden sollten und wie der Bewertungsprozeß zur Ermittlung der gewünschten Informationen gestaltet werden muß. 相似文献
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The end of over unit products of more than Chinese firms have passed the quality grade certification for liquor products. These products involve distilled spirits beer wine yellow wine fruit syrup wine others cover over % of the national top-branded liquor products.…… 《中国标准化(英文版)》2008,25(1):30
The end of 2007, over 200 unit products of more than 80 Chinese firms have passed the quality grade certification for liquor products. These products involve distilled spirits, beer, wine, yellow wine, fruit syrup wine and others, and cover over 80% of the national top-branded liquor products.…… 相似文献
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Surface characterization and microstructure studies are performed on chemical vapor deposited (CVD) tungsten coating. There is about 2 μm thickness diffusion layer of tungsten in the molybdenum substrate. The thermal shock test shows tungsten coating has good adhesion with molybdenum substrate, but the elements of oxygen and carbon in the tungsten coating have the bad affection to the adhesion. The result of high-temperature diffusion experiment is the diffusion rate from molybdenum substrate to tungsten coating is faster. 相似文献
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《材料科学技术学报》2014,(11):F0003-F0003
Journal of Materials Sciences & Technology is a monthly journal for the rapid dissemination of new, impor- rant results in material and related fields. Submission Electronic files of MS Word and PDF are acceptable. Please visit http://www.jmst.org and submit online. 相似文献