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三维坐标中测量曲面的定位 总被引:5,自引:0,他引:5
采用最小二乘法 ,在三维空间中将实际曲面与标准曲面进行拟合 ,使其满足每个测量点到标准曲面的距离平方之和达到最小的原理。该方法不仅可以确定曲面面型误差 ,同时还可以计算出曲面在空间的真实位置 ,从而降低了对测量定位基准面的要求 ,因此本方法对三坐标测量曲面有重要意义 相似文献
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纯弯矩梁型应变计灵敏系数测定装置的误差分析和精度评定方法(一) 总被引:1,自引:0,他引:1
邓足斌 《仪表技术与传感器》1999,(7):10-12,42
为检定纯弯矩梁型应变计灵敏系数测定装置的精度。国际上60年代 以来都是从应变定义出发,总想直接测定标定梁表面的准确应变值。由于测量原理不理想和仪表分辨精度不够高等因素,一直未得到较理想地解决。 相似文献
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数控机床误差补偿技术及应用测头系统误差分析和补偿技术 总被引:3,自引:0,他引:3
在机测量是机床加工过程质量监控的重要手段。文章对触发式测头的结构、测量原理、测头系统和测量过程中的误差源进行分析和处理,给出误差补偿和控制措施,以提高测量精度。该技术对推广和应用在机测量技术有重要意义。 相似文献
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研究了一种基于光电耦合器件(CCD)及图像处理技术的聚甲基丙烯酸甲酯(PMMA)微流控芯片微通道几何尺寸的测量系统,论述了该系统的关键技术及其实现方法,包括图像的预处理、二值化、轮廓提取以及微通道尺寸的测量等。利用该系统测量的微通道几何尺寸(1~1 000 μm)与轮廓仪和万能工具显微镜的测量结果吻合很好,最大测量误差为2 μm(半深宽度),分析了测量误差产生的原因。检测实验结果表明:该检测方法提供的微通道几何尺寸评定正确可行、通用性好、应用简便,还可以避免轮廓仪在深结构测量中的误差。 相似文献
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The form errors of three-dimensional surfaces have an effect on the proper functioning of an assembly. Methods for evaluating form errors of surfaces of spherical and cylindrical components are available. However, in most machines and instruments the functional components are axisymmetric, e.g. spindles, and have varying geometry in the form of steps, tapers etc. Evaluation of the form errors at different zones on the component as well as a form error characteristic of the whole component is required in such cases. To do this coordinate data or circularity traces are obtained at different horizontal sections using a coordinate measuring machine or a roundness measuring instrument respectively and the required form error is then evaluated. Different algorithms developed for fitting the axis of the component which is the first step in the evaluation of form errors are described. The method of normal least-squares fitting was found to be superior to the general least-squares method. 相似文献
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ASSESSING THE DYNAMIC ERRORS OF COORDINATE MEASURING MACHINES 总被引:2,自引:0,他引:2
0INTRODUCTIONCoordinatemeasuringmachines(CMMs)arewidelyusedinthedevelopingmodernmanufacturingindustry.Inmanycases,fastproduc... 相似文献
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大型望远镜测角系统误差的修正 总被引:1,自引:0,他引:1
由于大型望远镜转台轴系对测角精度要求较高,本文研究了测角数据系统的误差修正技术。分析了测角数据误差产生的原因,对测角元件误差、安装误差、被测轴系误差进行了讨论,指出轴系测角分系统的误差规律符合谐波方程,故提出采用谐波方程式来表达误差规律。针对工程应用,建立了基于傅里叶级数的简化谐波方程误差公式,用谐波方程算法和多项式拟合算法对系统误差进行修正。在一个望远镜垂直轴转台进行了试验验证,结果显示测角精度峰值由原来的3.81″提高到了1.06″。实验表明,基于傅里叶级数的修正算法,较好地符合误差分布规律;采用系统误差修正技术,可以对系统综合误差统一修正,能够有效提高系统测角精度。 相似文献
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数显式小转矩测量仪测量精度设计 总被引:1,自引:0,他引:1
】从数显式小转矩测量仪的结构原理和仪器本身所产生的随机误差出发,分析并计算了仪器各环节产生的误差。提出了满足使用要求,提高测量精度的方法和途径。 相似文献
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Machine tool calibration: Geometric test uncertainty depends on machine tool performance 总被引:1,自引:0,他引:1
In order to show a sufficient geometric performance, every machine tool has to be calibrated geometrically before it may come into operation. The geometric machine errors have to be identified. They can afterwards be compensated either mechanically or numerically in the machine control.Machine tools are usually calibrated geometrically by performing a sequence of different measurements to identify single errors such as squareness errors between linear axes, straightness errors, positioning errors etc.The uncertainty of such measurements is of course affected by the uncertainty of the measuring device under the given environmental conditions. Methods to describe such influences are widely known and applied.Other effects having an impact on the error parameters to be determined (e.g. squareness errors) are dependent on the performance of the machine tool under test. Neglected geometric errors, hysteresis and thermal drift affect the measurement result. Such effects may be much more important contributors to the overall test uncertainty than the measurement uncertainty of the measuring device.In this paper the problem of error interdependencies leading to a worse test uncertainty is explained. The occurrence of such effects is shown with exemplary measuring results. A method for estimating the overall test uncertainty even for complex measurements is introduced. The dependence of the test uncertainty on the geometric machine performance is explained. 相似文献
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刀具预调仪的结构设计及误差的补偿方法 总被引:2,自引:0,他引:2
针对大部分刀具预调仪仅能测量刀具轮廓顶点坐标的情况,提出刀形测量的必要性。分析了刀具预调仪存在的13种结构误差的产生原因、性质及其对测量的影响,在现有结构的基础上给出了较为合理的刀具预调仪的结构方案设计,以及对结构误差的补偿方法。 相似文献
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Development of an optical measuring system for integrated geometric errors of a three-axis miniaturized machine tool 总被引:2,自引:2,他引:0
Wei Wang Sung-Hwan Kweon Chang-Soon Hwang Nam-Cheol Kang Young-Suk Kim Seung-Han Yang 《The International Journal of Advanced Manufacturing Technology》2009,43(7-8):701-709
Miniaturized machine tool (mMT) is one kind of downsized machine tool derived from conventional machines to manufacture miniature parts. However, it is extremely difficult to calibrate an mMT due to its small dimension. This paper presents a novel method that uses laser diode and optics to measure integrated geometric errors (three translation errors and three rotational errors). The squareness error between two axes is calculated by the least-square method. These seven errors are acquired simultaneously in one setup for each motion direction. The proposed measuring system consists of laser diodes, beam splitters, and 2D position sensing detectors (PSDs). The relationship between the PSD readings and the geometric errors calculated by the algorithm based on homogeneous transformation matrix is derived according to the configuration of measured mMT. Simulation is carried out to prove the validity of this algorithm. Sensitivity analysis based on the mounting errors of system components is also presented in this paper. Finally, an experiment is executed to verify the feasibility of the proposed measuring method. 相似文献