基于Matlab的平面度误差最小区域法评定

平面度是形状公差的主要项目之一,其误差的测量与评定在几何量测量中有着重要的意义.分析了常用的近似评定法(三点法、对角线法、最小二乘法等)存在的局限性,根据最小区域法的定义,给出了基准平面方程及平面度误差评定目标函数数学模型的建立方法,并举例说明了采用Matlab进行平面度误差的计算.结果证明该方法利用Matlab只需要进行简单的矩阵运算,具有简单实用的特点.     

基于AutoCAD2000的图解法确定平面度误差

本文利用画法几何的原理，基于AutoCAD2000的图解法确定平面度误差，并针对一个应用实例给出了图解过程和最终结果。     

基于新型凸包法的平面度误差评定

在传统凸包法计算平面度误差的基础上,结合测点空间分布特点,提出了一种新的三维点集的凸包构建方法。通过将测点向xy平面投影,快速确定首轮凸包顶点,然后由本轮的相邻凸包顶点建立棱线,在剩余点中如果有一点使得该点和棱线构成的平面为凸包平面,则该点即为下一轮凸包顶点之一。通过这种方式,由本轮顶点,得到下轮顶点,依轮循环搜索直至无法得到新的凸包顶点,从而实现凸包的构建。在进一步利用凸包进行平面度误差评定过程中,对所有测点进行拟合得到最小二乘平面,利用构建凸包过程中得到的凸包平面方向向量及棱线向量数据,计算其与最小二乘平面的夹角,夹角较小的元素优先进行最小包容区域判别,以提高平面度误差的计算效率,最后通过与相关文献的数据进行比较,验证了该方法的正确性。     

平面度误差评定算法及程序设计

平面度是评定产品质量的指标之一.随着测量技术的不断进步,影像测量仪被广泛应用于平面度的测量.采用最小二乘法的算法原理,编写平面度误差评定程序并将其嵌入影像测量仪软件中,对影像测量仪自动测量的数据进行处理.实验结果表明:该算法能够快速评定平面度误差,在生产实际应用中效果较好.     

大型平面平面度误差的可视化数据处理

通过对平面度误差评定的4种常用方法的分析,利用MATLAB语言强大的数值计算和绘图功能,编写出基于水平仪和光学自准直仪的大型平面平面度误差检测程序.检测人员只要从界面上输入测量数据、仪器分度值及桥板跨距,选择数据处理方法,便可直接得出平面度误差值,并绘出直观形象的三维模拟图形.实例证明,该软件算法正确,操作简便,界面友好.     

平面度误差检测方法的研究

介绍了平面度误差的几种常用检测方法及其特点,并针对其存在的问题,提出了一种在线检测平面度的测量方法.采用此方法可以有效地缩短测量时间,降低测量成本,提高加工和检测的自动化程度,同时也可减轻工人的劳动强度.     

超精密平面度在线检测方法研究

磨削问题过实验,效性。介绍了一种用最小二乘逐次两点法对超精密平面度进行在线检测与误差分离的方法;针对平面光学玻璃设计了一套在线测量系统,所提出的方法可以精确而快速地分离出被测平面移动的导轨运动误差,通验证了该测量方法能在机床上直接测量工件的平面度误差,消除基准误差,从而保证实现在线测量的有     

一种圆度误差最小区域评价方法

针对圆度误差的评价方法,介绍一种利用最小区域法评价圆度误差的计算方法.研究最小区域圆度误差评价机理,建立基于弦线截交关系的最小区域圆度误差评价模型,并得出了利用弦线相对变化搜索特征点的方法.通过内、外接圆的两次弦线变换关系,利用弦线变换产生的虚拟中心可以准确确定最小区域圆的"2+2"特征关系,达到了快速、精确利用最小区域法评价圆度误差的目的.通过分析表明,基于弦线截交关系的最小区域圆度误差评价方法计算效率高、易于实现且具有较高的评定精度,也为圆度误差评价提供一种新的方法和思路.     

一种新的大平面平面度测量方法

针对大平面度测量,设计一种新的平面度测量系统,该系统摒弃了高精度大平面度测量所需要的高精度导轨、高精度光学平面等,而是以液面作为一个平面基准,用干涉仪标定出测量系统的系统误差,然后用接触式传感器测量被测件,再进行误差分离,将系统误差从测量误差中分离出去,从而达到对大平面度的高精度测量。     

一种联机检测轮廓加工误差的新方法

对一个机横加工而成的机械零件来说,由于实际使用的需要。不仅对零件的尺寸精度有一定要求,而且对零件的轮廓精度也有一定要求。本文采用联机检测的方法,在数控机床或加工中心上测量零件的轮廓加工误差。本文提出了一种采用一维传感器测量两维工件轮廓加工误差的新方法。理论分析和实验结果表明,此方法是可靠的,具有较高的精度。     

Auto-detection of strip area in 3D measurement

3D measurement is an important task for modern manufacturing, because 2D measurement cannot meet the increasing requirements for quality control in engineering. Among all, 3D recovery methods, by using structural lighting system are the most popular methods because of its non-destructive character. The acquiring of lighting strips, which have to be projected on the object is the most important work to ensure later matching work. In the former research, the position of the stripes in the image was very difficult to locate and must be drawn manually. Therefore, the aim of our research is to find a method to auto-detect the strip area. FFT (fast Fourier transform algorithm) are used to analyze the image character by row and by column. From the FFT result, in the power spectrum the strip area and non-strip area can be distinguished clearly. So the strip area can be marked exactly on the image, and image process algorithm can be used to pick up the strips only on this area. After the matching and 3D recovery algorithm, the 3D shape of the object can be plotted. The auto-detection strip algorithm can save a lot of time for the 3D measurement, automatically complete the 3D recovery procedure, and bring convenience to operators.     

板料变形的投影栅三维快速测量技术研究

目前, 国内外研究的物体形面光学三维测量系统, 多用于静态物体的三维测量, 测量时间较长。本文研究了一种投影栅三维形面快速测量系统, 可应用于处于动态状态的物体的三维测量。文中介绍了其原理、相展开以及双CCD相位周期匹配等关键技术, 并且应用该系统对汽车侧围板变形进行测量。精度验证表明, 系统在测量范围内误差为10μm量级, 可用于工业快速测量领域。     

Estimation and correction method for the two-dimensional positionerrors of a planar XY stage based on motion error measurements

This paper describes an estimation and correction method for the two-dimensional (2D) position errors of a planar XY stage that is driven along the Y-axis by two linear motors. The 2D position errors of the stage were estimated and corrected based on measured motion errors from a conventional laser interferometer system. To compensate for the planar XY stage 2D position errors, corrections were introduced for the yaw, perpendicular, straightness and 1D position errors along each axis, which are predominantly caused by linear scale, yaw, and pitching motion errors. The effect of the motion error corrections was evaluated by diagonal measurements based on the ISO230-6 standard and six different 1D position error measurements along the X and Y-axes. By applying error motion corrections, the diagonal systematic deviation at the center point was improved from 499.7 μm to 1.16 μm, and the estimated maximum 2D position errors were improved to −0.263 and 0.530 μm in the X and Y directions, respectively. The diagonal systematic deviation at a corner point was 1.23 μm and the estimated maximum difference between the corner and center points improved from −2.603 and 2.603 μm to −0.05 and 0.12 μm in the X and Y directions respectively.     

A new method and instrument for measuring circular motion error of NC machine tools

A new method and instrument for measuring circular motion error of numerical control (NC) machine tools are described in this paper. The instrument consists of a linear displacement transducer bar with two balls at each end and a high accuracy rotary encoder. The radius variations are detected by the transducer and the rotation angle of the bar is measured by the rotary encoder while the machine is moving in a circular path. The measuring area is circular except for a small area around the center of the disc. The bar can be expanded and contracted along its axis for different application. The instrument has a compact structure and can be installed on a machine tool simply and quickly. It is shown by the experimental results that the instrument has good repeatability and high precision of measuring circular motion trajectories. The instrument can be widely used especially in the error-compensation and error-source project in the industrial application.     

A new method and device for motion accuracy measurement of NC machine tools. Part 2: device error identification and trajectory measurement of general planar motions

This paper describes in two parts a new method and device for measuring motion accuracy of NC machine tools. In the first part, the measurement principle and the characteristics of the prototype device have been presented and discussed. In the second part, an efficient and practical approach to identifying the errors of the proposed device after assembly is developed and evaluated. The approach ensures realising the aim of the investigation, i.e. to measure the most items of the motion accuracy, especially, to measure and assess the trajectory accuracy of a general planar motion of NC machine tools. The result of the identification experiment by using the prototype device on a machining centre for the prototype device is presented and it well verifies the validity and practicality of the approach. Some measurement results for the general planar motions of the machining centre are also shown, which sufficiently demonstrate the desirable capability of the proposed method and device.     

A new method of noncontact measurement for 3D micro pattern in semiconductor wafer: implementing a new optical probe

In this paper, a new type of noncontact/nondestructive measuring method has been developed, comprising a new optical probe, precision stages, and controllers. The new optical probe has been designed using the reflected slit beam through the optical window. The optical measurement system has been implemented around light illumination, optical lenses, optical window, and beam splitter. Efficient analysis algorithm has been developed in order to analyse the 3D micro pattern and some parameters of the surface. The developed system has been successfully applied to measure the wafer surface, giving nanometer vertical resolution.     

超声相控阵二维面阵实现三维成像研究进展

实现基于二维阵列的三维成像会遇到阵元多、通道数多、系统复杂、回波信号弱等困难。从阵元排列的设计着手,分析了时间-空间信号在离散有限长窗函数下的特征,推导出阵列设计的一般准则;依据此准则,根据脉冲回波场理论,在计算机模拟的基础上设计了8×8二维阵列;并利用该阵列实现了相控阵三维体数据的扫描和显示。扫描试验所得人工缺陷的三维图像呈现出良好的轮廓和走向等信息。     

基于误差分离技术的斜轧复杂型面轮廓度误差在线检测方法研究

文章提出了斜轧辊复杂型面轮廓度误差测量的解决方法,给出了大轴复杂型面测量系统的构成模型。在系统中采用了频域误差分离技术,并建立了最小二乘圆数学模型。对提高斜轧辊型面加工精度及斜轧件精度有较明显的意义。     

自动化三维精密测量技术及其在锻压领域的应用

面扫描三维测量技术具有非接触、测量速度快、精度高等优势,在锻压领域具有巨大的应用潜力.但是通用的面扫描三维测量设备在测量过程中易受测量规划、数据处理等人为因素影响,测量精度难以保证.为解决此问题,提出一种基于面扫描和六自由度机器手的自动化三维测量技术,该技术由六自由度机器手、三维测量头、控制系统等组成,能够充分利用机器手运动灵活、工作范围大的特点和面扫描测量速度快、精度高的优势.此外,该技术采用了一种基于矩阵直积的手眼标定算法,实现了多次测量数据的高精度自动拼合.实际应用表明,该技术能够实现复杂锻件等工业产品的快速、精确、自动三维测量和精度检测.