共查询到19条相似文献,搜索用时 140 毫秒
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基于多孔径重叠扫描拼接技术的圆柱度测量研究 总被引:1,自引:1,他引:0
提出了一种利用多孔径重叠扫描拼接技术的圆柱度非接触式测量新方法,可以有效地改进目前现有圆柱度测量方法中所存在的采样点不足、评定结果不统一等问题.该方法首先对圆柱体零件进行多个子孔径(单视角)的面形测量,其次,利用重叠区域面形信息建立相对空间位置关系,并通过坐标变换将各子孔径面形统一于同一坐标系下,从而实现完整面形的拼接测量.根据获得的圆柱体零件面形数据,可以实现零件圆柱度的精确评定.文中给出了基于多孔径重叠扫描拼接技术的光栅投射测量系统,计算机模拟和实验结果验证了拼接测量方法的可行性. 相似文献
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本文采用投影散斑相关法对芯片翘曲度进行了测量。利用单个CCD和单个投影装置多次扫描的方法,得到若干幅具有部分重叠区域的小图像,然后通过配准和拼接获得全景图像,实现整体测量。在拼接区标定若干控制点,然后以这些控制点为基准进行坐标变换实现重叠区域的配准和拼接,以提高分辨率、实现全场测量,得到芯片相对于标准平面的面内位移和形变。通过三角法标定,获得了离面位移和形变,从而完成了对手机屏幕芯片翘曲度的测量。与牛顿环测量法相比较,结果证明了投影散班方法测量芯片翘曲度的精度和可行性。 相似文献
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环形子孔径测试的迭代拼接算法及其实验验证 总被引:1,自引:0,他引:1
为了满足测量高精度、大口径光学元件的需要,在子孔径拼接和定位算法的基础上研究了环形子孔径迭代拼接算法。该算法可通过精确找出重叠点对和寻找最优位形两个步骤来简化。而后研究了该算法在环形子孔径拼接测量中出现的新问题,即如何确定重叠点的问题,并详细介绍了该算法的步骤。最后对160mm口径的抛物面进行了拼接测量实验, 拼接结果的PV值为0.186λ,RMS值为0.019λ,与自准直全口径测量结果基本一致。结果表明环形子孔径的迭代拼接算法能够满足非球面镜的高精度测量。 相似文献
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基于对多孔径拼接测量技术基本原理的研究,提出在拼接坐标变换时采用四元数法进行子孔径的旋转和平移,推导构建了多孔径拼接数学模型,并给出了确定载物台旋转轴线的测量方法。计算机模拟验证了该拼接测量方法的精确性,基于光栅条纹投射系统进行三维物体的拼接测量,实验结果证明了这种方法的有效性。与传统方法相比,该方法具有运算简单、速度快、精确等特点。 相似文献
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子孔径检测及拼接的目标函数分析法 总被引:4,自引:1,他引:4
利用子孔径检测及拼接的方法可以完成大口径面形的干涉测量,本文提出实现子孔径拼接的目标函数分析法,并通过建立每个子孔径的相关矩阵及相关向量。每个重叠区的拟合矩阵及拟合向量,实现了子孔径的拼接。该方法简单易行且避免了误差传递和积累。 相似文献
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利用子孔径检测及拼接的方法可以完成大口径面形的干涉测量,本文提出实现子孔径拼接的目标函数分析法,并通过建立每个子孔径的相关矩阵及相关向量,每个重叠区的拟合向量,实现了子孔径的拼接。该方法简单易行且避免了误差传递的积累。 相似文献
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一种圆柱度测量基准的误差分离方法 总被引:4,自引:0,他引:4
通过对主轴回转误差运动的分析,结合三点法圆度误差分离技术,提出了一种完全分离圆柱度测量基准误差的分离方法,即利用主轴回转轴线平均线、测量传感器及直行导轨之间的空间位置关系,建立相应的坐标系,在分离出被测截面圆度误差、最小二乘圆心初始坐标的基础上,完整地分离出影响圆柱度精密测量的径向回转运动误差和导轨的直行运动误差。该技术不仅可以消除测量基准误差对圆柱度测量精度的影响,还可以实现主轴回转误差、导轨直线度以及导轨对主轴平行度误差的精密测量,对高精度误差补偿加工和机床的精度检验也具有重要意义。 相似文献
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Measurement uncertainty is one of the most important concepts in geometrical product specification (GPS). The “Guide to the expression of uncertainty in measurement (GUM)” is the internationally accepted master document for the evaluation of uncertainty. The GUM method (GUMM) requires the use of a first-order Taylor series expansion for propagating uncertainties. However, when the mathematical model of measurand is strongly non-linear the use of this linear approximation may be inadequate. Supplement 1 to GUM (GUM S1) has recently been proposed based on the basis of probability density functions (PDFs) using the Monte Carlo method (MCM). In order to solve the problem that the number of Monte Carlo trials needs to be selected priori, adaptive Monte Carlo method (AMCM) described in GUM S1 is recommended to control over the quality of the numerical results provided by MCM.The measurement and evaluation of cylindricity errors are essential to ensure proper assembly and good performance. In this paper, the mathematical model of cylindricity error based on the minimum zone condition is established and a quasi particle swarm optimization algorithm (QPSO) is proposed for searching the cylindricity error. Because the model is non-linear, it is necessary to verify whether GUMM is valid for the evaluation of measurement uncertainty of cylindricity error. Then, AMCM and GUMM are developed to estimate the uncertainty. The procedure of AMCM scheme and the validation of GUMM using AMCM are given in detail. Practical example is illustrated and the result shows that GUMM is not completely valid for high-precision evaluation of the measurement uncertainty of cylindricity error if only the first-order terms in the Taylor series approximation are taken into account. Compared with conventional methods, not only the proposed QPSO method can search the minimum zone cylindricity error precisely and rapidly, but also the Monte Carlo simulation is adaptive and AMCM can provide control variables (i.e. expected value, standard uncertainty and lower and higher coverage interval endpoints) with an expected numerical tolerance. The methods can be extended to the evaluation of measurement uncertainty of other form errors such as roundness and sphericity errors. 相似文献
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Precision modeling of form errors for cylindricity evaluation using genetic algorithms 总被引:9,自引:0,他引:9
A heuristic approach is proposed in this paper to model form errors for cylindricity evaluation using genetic algorithms (GAs). The proposed GAs method shows good flexibility and excellent performance in evaluating the engineering surfaces via measurement data involved with randomness and uncertainty. The numerical-oriented genetic operator is used as a basic representation for error modeling in the paper. The theoretical basis for the proposed Gas-based cylindricity evaluation algorithms is first presented. The performance of the method under various combinations of parameters and the precision improvement on the evaluation of cylindricity are carefully analyzed. One numerical example is presented to illustrate the effectiveness of the proposed method and to compare the Gas-based modeling results with those obtained by the least-squares method. Numerical results indicate that the proposed GAs method does provide better accuracy on cylindricity evaluation. The method can also be extended for solving difficult form error minimization and profile evaluation problems of various geometric parts in engineering metrology. 相似文献
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子孔径变换与多孔径扫描拼接技术 总被引:7,自引:0,他引:7
多孔径扫描拼接技术是检测高精度大孔径平面面形的有效手段。利用子孔径变换实现多孔径扫描拼接,具有精度高,可靠性好,数据处理简单的特点。本文给出了数学模型,并分析了实测结果。 相似文献
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