新一代产品几何技术规范测量不确定度理论及应用技术

研究了测量不确定度的统一评定和表述方法，用新一代产品几何技术规范（GPS）基于GUM及系统量化统一的新思路，拓展了测量不确定度的概念，规范了测量不确定度的评定程序。在此基础上，将测量不确定度的概念拓展至GPS系统，利用拓展后不确定度的统计、量化特性，将产品的功能、规范与测量评定量化集成。通过不确定度的经济杠杆调节作用，实现过程资源配置的统筹优化，提高产品的综合效益。     

现代产品几何技术规范(GPS) 的不确定度理论及应用技术研究

新一代GPS（generation geometrical product specification）在测量不确定度的基础上扩展了不确定度的概念,将不确定度应用到几何产品的“功能、规范、认证”的全过程。文中着重分析新一代GPS不确定度的构成、相互关系及GPS过程量化统一的内在规律性;明确不确定度与操作算子之间的关系,揭示GPS不确定度理论的概念基础、应用规律及技术经济性;研究新一代GPS基本原则与不确定度之间的关系规律,给出减小GPS不确定度的对策和措施;并在此基础上,以产品质量认证为例,进一步分析研究GPS测量不确定度规范及其应用技术。     

基于GPS的圆柱度测量不确定度分析与评定

本文在GPS不确定度理论的基础上,阐述了PUMA测量不确定度管理程序及其关键环节;在对圆柱度的测量过程研究的基础上,分析了圆度仪测量圆柱度的测量不确定度影响因素及评定模型,利用PuMA管理程序,实现了圆度仪测量圆柱度的测量不确定度的规范评定,证明了PUMA管理程序可用于几何特征量测量或者测量设备计量特征校准的测量程序.     

基于GPS的测量不确定度评定方法分析

本文阐述了新一代GPS不确定度理论的形成、发展,以及在实现几何产品规范设计与计量认证统一中的重要作用;基于测量不确定度贡献因素的分析,着重研究了测量不确定度的评定方法、模型及应用技术,为实现测量不确定度评定管理的规范统一奠定必要的技术基础。     

测量不确定度评定与分析

测量不确定度是在当代国际贸易和技术交流活动中,各国用于表征测量结果的质量优劣的一种先进方法,章简要描述了测量不确定度的评定与分析方法,并举例说明其应用分析过程。     

基于新一代GPS的圆柱不确定度评定技术研究

介绍了新一代GPS标准体系下不确定度的构成,研究了规范阶段不确定度的管理程序,给出了基于该管理程序的实例,详细分析了对圆柱规范表面模型进行相应操作过程中不确定度的产生和评定.在此基础上给出如何应用规范过程得到的不确定度对测量认证进行指导的建议,通过对测量认证阶段不确定度管理程序的介绍,分析了新一代GPS标准体系下圆柱不确定度的产生和传递关系.     

万能工具显微镜长度测量的不确定度评定与分析

万能工具显微镜是一种常用的几何量计量仪器，用它来测量某工件的长度，对测量结果进行不确定度评定与分析。指出了不确定度计算中存在的现实问题。     

直径图样标注的规范不确定度分析

规范不确定度是新一代产品几何规范(GPS)不确定度理论体系中的重要组成部分.通过对规范不确定度的成因进行探析,给出了规范不确定度评定的管理流程,并以尺度规范中的直径规范为出发点,对目前存在的典型直径规范样式的规范不确定度进行了评定.研究结果表明,目前存在的直径图纸规范样式存在很大的规范不确定度,应对其修正.同时,研究还表明,实施新一代GPS对产品制造全过程中的资源优化分配、降低成本具有重要意义.     

测量误差与测量不确定度浅析

分析测量误差的来源、分类，测量不确定度的定义、表示方法、评定方法及测量误差与测量不确定度的联系与区别。     

测量不确定度评定与表示

主要介绍了测量不确定度、标准不确定度的评定方法,合成标准不确定度和扩展不确定度的评定.     

Monte carlo method for the uncertainty evaluation of spatial straightness error based on new generation geometrical product specification

Straightness error is an important parameter in measuring high-precision shafts. New generation geometrical product specification(GPS) requires the measurement uncertainty characterizing the reliability of the results should be given together when the measurement result is given. Nowadays most researches on straightness focus on error calculation and only several research projects evaluate the measurement uncertainty based on "The Guide to the Expression of Uncertainty in Measurement(GUM)". In order to compute spatial straightness error(SSE) accurately and rapidly and overcome the limitations of GUM, a quasi particle swarm optimization(QPSO) is proposed to solve the minimum zone SSE and Monte Carlo Method(MCM) is developed to estimate the measurement uncertainty. The mathematical model of minimum zone SSE is formulated. In QPSO quasi-random sequences are applied to the generation of the initial position and velocity of particles and their velocities are modified by the constriction factor approach. The flow of measurement uncertainty evaluation based on MCM is proposed, where the heart is repeatedly sampling from the probability density function(PDF) for every input quantity and evaluating the model in each case. The minimum zone SSE of a shaft measured on a Coordinate Measuring Machine(CMM) is calculated by QPSO and the measurement uncertainty is evaluated by MCM on the basis of analyzing the uncertainty contributors. The results show that the uncertainty directly influences the product judgment result. Therefore it is scientific and reasonable to consider the influence of the uncertainty in judging whether the parts are accepted or rejected, especially for those located in the uncertainty zone. The proposed method is especially suitable when the PDF of the measurand cannot adequately be approximated by a Gaussian distribution or a scaled and shifted t-distribution and the measurement model is non-linear.     

新一代产品几何技术规范(GPS)对制造业的影响

介绍了产品几何技术规范(GPS)的发展概况,归纳出新一代GPS体系倡导功能公差理念、按计量学设计公差、体现并行工程思想、实现与CAx系统有效集成等4大特点,分析了新一代GPS体系将给制造业带来的积极影响,探讨了目前的研究方向,提出了加快中国GPS标准应用平台建设的若干建议。     

Measurement uncertainty evaluation of optical multi-sensor-measurements

Optical coordinate metrology facilitates the set-up of in-line applications for quality inspection in shop floor for a variety of products. Yet, for situations with high requirements it is not possible to fulfill all demands by devices based on a single measurement principle. To enable high measurement rates and as well as precise and contact-less data acquisition, a combination of subsystems with different principles and properties has to be implemented. To assure the fitness of an optical multi-sensor-measurement system combining a shadow system and a light-section system for the in-line inspection of concave extruding profiles, an experimental measurement uncertainty analysis has been performed. To this aim, a prototype is set-up and the effect of typical environmental influences like dust, object’s vibrations, the illuminations’ pitch error or extraneous light, is examined. Subsequently, the measurement system is evaluated under shop floor conditions and the results are analyzed.     

Flatness error evaluation and verification based on new generation geometrical product specification (GPS)

New generation geometrical product specification (GPS) links the whole course of a geometrical product from the research, development, design, manufacturing and verification to its release, utilization, and maintenance. Measurement process is one of the most important part of verification/inspection in the new generation GPS. With the knowledge-intensive and globalization trend of the economy, unifying the evaluation and verification of form errors will play a vital role in international trade and technical communication. Considering the plane feature is one of the most basic geometric primitives which contribute significantly to fundamental mechanical products such as guide way of machine tool to achieve intended functionalities, the mathematical model of flatness error minimum zone solution is formulated and an improved genetic algorithm (IGA) is proposed to implement flatness error minimum zone evaluation. Then, two evaluation methods of flatness error uncertainty are proposed, which are based on the Guide to the Expression of Uncertainty in Measurement (GUM) and a Monte Carlo Method (MCM). The calculating formula and the propagation coefficients of each element and correlation coefficients based on GUM and the procedures based on MCM are developed. Finally, two examples are listed to prove the effectiveness of the proposed method. An investigation into the source and effects of different uncertainty contributors for practical measurement on CMM is carried out and the uncertainty contributors significant are analyzed for flatness error verification. Compared with conventional methods, the proposed method not only has the advantages of simple algorithm, good flexibility, more efficiency and accuracy, but also guarantees the minimum zone solution specified in the ISO/1101 standard. Furthermore, it accords with the requirement of the new generation GPS standard which the measurement uncertainty characterizing the reliability of the results is given together. And it is also extended to other form errors evaluation and verification.     

Design and analysis of experiments in CMM measurement uncertainty study

In applying a coordinate measuring machine to measure a mechanical object, many factors affect the measurement uncertainty. Although a number of studies have been reported in evaluating measurement uncertainty, few have applied the factorial design of experiments (DOE) to examine the measurement uncertainty, as defined in the ISO Guide to the Expression of Uncertainty in Measurement (GUM). This research applies the DOE approach to investigate the impact of the factors and their interactions on the uncertainty while following the fundamental rules of the GUM. The measurement uncertainty of the location of a hole measured by a coordinate measuring machine is used to demonstrate our methodology.     

Measurement uncertainty limit analysis with the Cramér-Rao bound in case of biased estimators

The Cramér-Rao lower bound has been proven to be a valuable tool for determining the minimal achievable measurement uncertainty and for analyzing the performance of estimators in terms of efficiency. While this is common for unbiased estimators, a bias does often occur in practice. The performance analysis of biased estimators is more difficult, because the bias has to be taken into account additionally. Furthermore, not the behavior of the biased estimator is finally of interest in measurements, but the behavior of its bias-corrected counterpart. In order to simplify the required performance analysis for biased estimators, the relation between the efficiencies of the biased and the bias-corrected estimator is derived. As result, both efficiencies are shown to be (at least asymptotically) identical. Hence, the bias-corrected estimator attains the Cramér-Rao bound if and only if the biased estimator attains its Cramér-Rao bound. Furthermore, the mean square errors become minimal if and only if the estimators reach the Cramér-Rao bound. Consequently, the optimality of the bias-corrected estimator can also be judged by evaluating the mean square error of the biased estimator.     

虚拟齿轮测量中心及其应用

针对齿轮测量中心及其误差检定的复杂性,提出了虚拟齿轮测量中心(VGMC)的基本构想,分析了虚拟齿轮测量中心的系统组成.虚拟齿轮测量中心不仅支持测量过程仿真,还能进行不确定度检定,文中对其应用进行了深入探讨.     

传感器测量不确定度的卷积评定方法

测试技术的快速发展确保了测量不确定度在各个行业中应用的必要性,其中对电子产品的评估是一个重要的方面.作为测试技术的基础组成部分,传感器的测量不确定度评估就显得尤为重要.本文分析了其主要不确定度来源并讨论了常用评估方法;为克服GUM方法的不足,最后提出引入卷积的评定方法,利用Matlab编程实现分布的合成,从而证实了卷积的方法更能清晰准确地显示被测量的分布情况.     

LED在线测试中的PLF测量不确定度分析

分析了LED定位不确定度,探头光谱失配和LED快速测试上电脉冲三方面对LED在线测试中部分光通量(PLF)测量不确定度的影响,并对光强分布为叶子形的LED进行了计算与实验。结果表明,5mm的水平测试位置不确定度,5°的机械轴不确定度,0.5mm的测试距离不确定度及200ms的快速测试上电脉冲一般能满足PLF测量较高的精度要求,光度探头的光谱失配会造成较大的不确定度,必要时应给予校正。所做的工作对LED在线测试具有实际指导意义。