θFXZ型测量机的回转轴线标定方法

回转轴线的标定技术是保证θFXZ型测量机测量精度的一项关键技术。针对该型测量机没有y方向运动的特点,分析了其内外径测量原理,讨论了回转轴线标定误差与内外径测量误差的关系,并提出了一种基于环形标准件内孔、外圆的测量结果,快速标定回转轴线的方法。试验结果表明:利用该方法进行θFXZ型测量机的回转轴线标定,标定后,测量机对其它型号环形标准件的测量误差在±0.001 mm以内。该方法实现了对回转轴线的精确标定,同时操作简单,可以制定标定软件,实现回转轴线的软件自动标定。     

回转体测量机高精度标定技术研究

回转体测量机由同转工件台和测量架组成,能够在工件一次装卡条件下对回转体零件的内外轮廓参数进行高精度的快速检测.根据该测量机的结构特点,分析了测量机的各项系统误差,提出了测量架运动直线与回转轴线之间平行度、测头的测量方向与同转轴线的垂直度、测头偏心等系统误差的标定方法,建立了标定数学模型,剔除了由于标准件加工、安装等不确...     

深孔类杯形零件内胀法同轴度测量仪

图1为冷挤压深孔类杯形件,内孔与外圆具有同轴度要求。此类零件同轴度的检测可以用图2a所示圆度仪或类似量仪来进行。其特点是测量精度较高、但仪器的结构复杂、价格昂贵,且检测时必须先调整被测零件,使其基准轴线与仪器主轴的回转轴线同轴、故检测效率低、不适合大批量零件生产的现场检测需     

非接触激光测头测量轴线标定系统

提出一种用于三坐标测量机的非接触激光测头的标定系统，该系统利用位置敏感探测器和特别设计的测头夹具机构对非接触激光测头测量光束的轴线进行调整，使其通过测头回转体的回转中心。文中对具体的夹具结构标定方法以及数据分析方法做了详细的论述。     

用游标卡尺测量内孔锥度辅具

<正> 该辅具(苏联发明证书1145237)可高效测量内孔锥度,能直接在加工机床上进行测量。辅具由板2(用于与游标卡尺尺身牢固连按)、三个固定测头3、滑动测头4、拉簧5和直尺1(用于与游标卡尺尺框牢固连接)构成。直尺1与滑动测头接触的斜度段按式a=dtgβC来确定。式中:a—直尺斜面上升值;d—两侧头轴线间的距离;β—读数时线值与角度值之比;C—直尺斜面长度坐标(即直尺移动距离C时上升a——译注)。测头的长度根据被测孔来确定。     

两端轴承座孔的同轴度智能检测仪

在几何量测量中,同轴度误差比较常用,但又很不好检测.本文介绍用气动测量两端孔的同轴度误差,采取建立公共轴线的方法,在两端孔同时插入气动测头,在保证上下两个气动测头同轴的基础上,工件旋转,通过数据采集和工控机处理并显示测量结果.是一种机械电气一体化的综合自动测量仪器.操作简单、检测效率高、精度高的专用仪器.     

两孔同轴度的气动测量

一、两孔同轴度气动测量原理 根据 GB 1183-80规定,同轴度公差带是直径为公差值t,且与基准轴线同轴的圆柱面内的区域(图1)。 按照这一定义,同轴度误差应等于被测轴线至基准轴线最大距离e的两倍。而当采用气动进行测量时,在测头定位基准轴线和基准孔轴线一致的条件下,测头转一周,在气动量仪上所显示的测量喷嘴处间隙的最大变化量,正好等于这一数值。也就是图2中(x1一x2)的 当测量喷嘴不在孔端,同轴度误差可按比例折算取最大值。 除测头定位基准轴线和被测基准孔轴线要求尽量一致外,整个测头还要求轴向定位。本试验采用平面,钢球定位。试验证…     

气动内孔测量头和校对规

<正> 气动测量头是气动测量中直接用于测量工件的尺寸、几何形状和位置偏差的传感器.气动内孔测量头用于测量孔尺寸。它是由进气管路、测量喷嘴及测量头体所组成.当被测工件的孔径尺寸变化时,会引起气动量仪上的气动参量变化,从而实现精密测量。气动参量的变化信号是由气动内孔测量头输出的。根据测量的工作原理,气动内孔测量头分为非接触式和接触式两类。     

气动在半自动检验机上的应用

最近我们研究成功一台测量泵体相互位置精度的半自动检验机。采用气动测量原理,所有执行机构均是气缸,并采用气动近接传感器、气动逻辑元件等组成的控制回路。下面进行简单的介绍。 一、概况 1.被测工件及测量参数 被测工件为A型喷油泵泵体(如图1所示),被测参数为。 4—φ24孔对A—B孔轴线的垂直度; 4—φ14孔对 A—B孔轴线的垂直度;两侧面对 A—B孔轴线的垂直度。 2.测量效率 每分钟测3件。 3.测量结果显示形式 灯光显示检验结果。大绿灯亮表示所有被测参数合格。大红灯亮表示至少有一被测参数不合格,不合格参数由小红灯指示。 汉译式数…     

基于机器视觉的叶型孔测量技术研究

为了充分应对涡轴发动机中的叶型孔测量难题,基于机器视觉原理研制了非接触式四坐标测量系统,主要由三维运动机构、气浮回转工作台、工业视觉测头和照明光源构成。系统采用背向照明方式,并基于模板匹配的图像拼接方法获取被测叶型孔的全景图像。在测量过程中,通过三维运动机构与气浮回转工作台的配合运动,使工业视觉测头采集到目标叶型孔的多幅局部图像,通过图像拼接得到其全景图像,而后由图像处理和叶型参数分析获得被测叶型孔的几何尺寸和轮廓度等型面参数。为了验证该系统的功能,选取某个静子组件外环作为被测零件,应用该系统对零件上分布的某个叶型孔特征进行测量,获取到相应的型面轮廓数据,从而验证了机器视觉测量方法在叶型孔测量方面的可行性和有效性。     

Minimal Realization of Linear Graph Models for Multi-physics Systems

An engineering system may consist of several different types of components,belonging to such physical"domains"as mechanical,electrical,fluid,and thermal.It is t...     

INTEGRAL EQUATION METHOD＇S APPLICATION IN HOLE-EDGE STRESS OF COMPOSITE MATERIAL PLATE WITH DIFFERENT SHAPED HOLES

The strength of composite plate with different hole-shapes is always one of the most important but complicated issues in the application of the composite material. The holes will lead to mutations and discontinuity to the structure. So the hole-edge stress concentration is always a serious phenomenon. And the phenomenon makes the structure strength decrease very quickly to form dangerous weak points. Most partial damage begins from these weak points. According to the complex variable functions theory, the accurate boundary condition of composite plate with different hole-shapes is founded by conformal mapping method to settle the boundary condition problem of complex hole-shapes. Composite plate with commonly hole-shapes in engineering is studied by several complex variable stress fimction. The boundary integral equations are founded based on exact boundary conditions. Then the exact hole-edge stress analytic solution of composite plate with rectangle holes and wing manholes is resolved. Both of offset axis loadings and its influences on the stress concentration coefficient of the hole-edge are discussed. And comparisons of different loads along various offset axis on the hole-edge stress distribution of orthotropic plate with rectangle hole or wing manhole are made. It can be concluded that hole-edge with continuous variable curvatures might help to decrease the stress concentration coefficient; and smaller angle of outer load and fiber can decrease the stress peak value.     

Non-monotonic material contrast in scanning ion and scanning electron images

30 keV Ga⁺ focused ion beam induced secondary electron (iSE) imaging was used to determine the relative contrast between several materials. The iSE signal compared from C, Si, Al, Ti, Cr, Ni, Cu, Mo, Ag, and W metal layers does not decrease with an increase in target atomic number Z₂, and shows a non-monotonic relationship between contrast and Z₂. The non-monotonic relationship is attributed to periodic fluctuations of the stopping power and sputter yield inherent to the ion–solid interactions. In addition, material contrast from electron-induced secondary electron (eSE) and backscattered electron (BSE) images using scanning electron microscopy (SEM) also shows non-monotonic contrast as a function of Z₂, following the periodic behavior of the stopping power for electron–solid interactions. A comparison of the iSE and eSE results shows similar relative contrast between the metal layers, and not complementary contrast as conventionally understood. These similarities in the contrast behavior can be attributed to similarities in the periodic and non-monotonic function defined by incident particle–solid interaction theory.     

Application of Feature Extraction through Convolution Neural Networks and SVM Classifier for Robust Grading of Apples

This paper proposes a novel grading method of apples,in an automated grading device that uses convolutional neural networks to extract the size,color,texture,an...     

分布动态载荷识别的抗噪处理

针对正交多项式频域法在用多种响应对矩形薄板进行载荷识别中抗噪性较差的问题,综合运用平均法、矩阵预处理和奇异值截断法等方法对之进行改善,并引入空间映射的思想,将该方法的应用范围拓展为复杂的模型.利用仿真算例,证实了该方法具有较好的抗噪性.     

基于MELTAC-N平台的核电厂安全级DCS环网研究与测试

针对工程实践中环网通讯相关问题的处理缺乏理论基础及国产化安全级DCS平台的开发缺乏成熟经验借鉴问题,对基于MELTAC-N平台核电厂安全级DCS环网的软硬件实现进行了研究。提出了安全级DCS环网双环网冗余设计、光切换开关设计等硬件设计方法,以及以RPR协议为基础,采用全数据收发策略的软件设计方法。在CPR1000安全级DCS平台上对安全级DCS环网的可靠性及实时性进行了评价,并进行了容错能力、响应时间及响应时间稳定性测试验证实验。结果表明,基于MELTAC-N平台安全级DCS环网软硬件设计具有较好的容错能力及响应时间稳定性。     

Short-Term Relay Quality Prediction Algorithm Based on Long and Short-Term Memory

The fraction defective of semi-finished products is predicted to optimize the process of relay production lines, by which production quality and productivity ar...     

End-to-End Multiview Gesture Recognition for Autonomous Car Parking System

The use of hand gestures can be the most intuitive human-machine interaction medium.The early approaches for hand gesture recognition used device-based methods....     

The laboratory simulation of abrasive wear

Abrasive wear has long been recognised as one of the most potentially serious tribological problems facing the operators of many types of plant and machinery; several industrial surveys have indicated that wear by abrasion can be responsible for more than 50% of unscheduled machine and plant stoppages. Locating the operating point of a tribological contact in an appropriate operational ‚map’︁ can provide a useful guide to the likely nature and origins of the surface degradation experienced in use, though care must be exercised in choosing the most suitable parameters for the axes of the plot. Laboratory testing of materials and simulations of machine contacts are carried out for a number of purposes; at one level for the very practical aims of ranking candidate materials or surface hardening treatments in order of their wear resistance, or in an attempt to predict wear lives under field conditions. More fundamentally, tests may be aimed at elucidating the essential physical mechanisms of surface damage and loss, with the longer term aim of building an analytical and predictive model of the wear process itself. In many cases, component surface damage is brought about by the ingress of hard, particulate matter into machine bearing or sealing clearances. These may be running dry although, more usually, a lubricant or service fluid is present at the interface. A number of standardised wear test geometries and procedures have been established for both two- and three-body wear situations, and these are briefly described. Although abrasive wear is often modelled as following an ‚Archard’︁ equation (i.e. a linear increase in material loss with both load and time, and an inverse dependence on specimen hardness) both industrial experience and laboratory tests of particularly lubricated contacts show that this is not always the case: increasing the hardness differential in an abrasively contaminated lubricated pair may not always reduce the rate of damage to the harder surface.     

ANGULAR DISTORTION ALLOWABLE VALUE AND ASSESS METHOD OF WELD ON COKE TOWER

A graph as the new engineering method for estimate the safety of bulging deformation of coke tower is proposed. Through stresses analysis of circumferential weld of coke tower and comparing the stresses produced by pressure with heat stress of steady state, residual stress, bending stress produced by both itself weight and wind loads, it showed that the stresses produced by pressure on the angle distortion are the main factor of equivalent stress of the combined stress. After comparing four kinds of stress controlling conditions, the relation to stress with depth of angular distortion, grade of curvature of angular distortion and half of region of angular distortion has been inferred. Graph of deformation allowable value of coke tower for different condition by angular distortion and half of region of angular distortion has been plotted. The five steps for its engineering use have been explained. The lighter the grade of curvature is, the larger of bulge allowance, may be, and the bigger of depth of angular distortion may pose too. For the coke tower with a popular structure of Dg 5 400 mm×28 mm, the result by graph is nearly more than the result of two formulas formed by other research, the error is less than 7.0%. But, the graph can be easily applied to different size of angular distortion.