新一代GPS语言中的要素、恒定类、特征及其应用

新一代GPS语言基于参数化几何学及向量代数等应用数学的方法，通过表面模型、要素、恒定类、恒定度、本质特征和方位特征等概念的引入和互补应用，实现了几何要素从定义、描述、规范到实际检验／认证过程中数字化控制功能的飞跃，比较有效地解决了产品在“功能描述、规范设计、检验／认证”过程中数学表达统一规范的难题。本文介绍了新一代GPS语言中所提出的要素、恒定类、特征等概念和定义，并讨论了它们的应用。     

新一代GPS测量不确定度管理程序及应用

现代产品几何技术规范GPS是ISO／TC213针对产品的设计与制造而规定的一系列宏观和微观的几何技术规范，已经由以几何学为基础的第一代GPS，发展到以计量学为基础的第二代GPS。第二代GPS标准体系将着重于提供一个适宜于CAX集成环境的、更加清晰明确、系统规范的几何公差定义和数字化设计、计量规范体系来满足几何产品的功能要求，它将成为信息时代集产品功能、规范和计量认证为一体的新型国际标准体系。     

现代产品几何技术规范(GPS)体系及应用分析

现代产品几何技术规范GPS(dimensional geometrical product specification and verification)是ISO／TC213针对产品的设计与制造而规定的一系列宏观和微观的几何技术规范，是所有机电产品的技术标准与计量规范的基础。随着全球经济的发展和科学技术的进步，尤其是随着CAD／CAM／CAQ(computer aided design／computer aided manufacture／computer aided quality)的应用和发展，新工艺、新技术、新材料的应用以及加工精度从微米到纳米的提高，ISO／TC213 GPS也随之发生了巨大的变化，已经由以几何学为基础的第一代GPS，发展到以计量学为基础的第二代GPS。文中在阐述ISO／TC213 GPS标准体系的形成、特点及发展趋势的基础上，对其构成思路及矩阵模型进行深入分析和研究，进一步揭示出其新一代GPS标准体系的构造模式规律及本质特征。     

GPS恒定类的产品规范与认证应用

基于新一代产品几何技术规范(GPS)恒定类特征理论,提出GPS恒定类特征建模方法,以及零件特征模型结构与恒定类的映射关系.开发了试验性GPS应用系统,完成了圆度公差实例的规范及认证过程,验证了在产品设计中应用GPS标准的方法.     

新一代产品几何量技术规范(GPS)标准体系研究

新成立的国际尺寸与产品几何技术委员会(ISO/TC213)提出了新一代GPS标准体系,该标准体系由基础、全局、通用和补充GPS标准组成。新一代GPS标准为产品的设计、制造、检验与评估提供了一套完整的技术规范。分析了新一代产品几何量技术规范(GPS)的系统模型、标准体系、关键技术、目前的研究方向与内容,以及我国新一代GPS标准体系的建立途径。     

运用GPS通用概念解释几何公差语义实例探讨

GPS通用概念由国际标准化组织ISO/TC213统一制定,是用来阐述产品几何要素定义、功能要求设定、规范设计、检验认证等操作的术语规范。针对传统公差采用文字和图示解释公差语义,从图样标注所获取的公差信息存在歧义性、模糊性及不一致性等问题,采用GPS公式化的语言对标注有平行度公差、同轴度和位置度公差并使用相关要求的图例进行了解释说明,清晰的表达了零件表面模型中理想要素与非理想要素的本质特征和方位特征以及对其进行要素操作和评估操作的要求。解释结果不但用于指导加工制造,也用于后续的计量评定,具有无歧义、一致性等特点。     

现代产品几何技术规范(GPS)中基于对偶性的操作技术及其应用

揭示现代产品几何技术规范（geometrical product specification and verification，GPS）中规范过程和检验／认证过程的物象对应关系，以及其表面模型存在着对偶性、操作技术存在着共性的内在规律性；井以几何误差的检验／认证过程为例，阐述利用操作及算子技术实现GPS计量过程数字化的可能性及应用规律；进一步明确基于对偶性的表面模型、操作及操作算子技术，对于实现GPS设计与计量的统一性、与CAX的集成性和数字化功能是至关重要的。     

支持并行工程的公差设计与评价研究

基于ISO／TC213的几何产品规范标准中的特征定义，提出了变动几何约束网络概念，并给出了它的运动学模型，阐述了在于该网络的完全约束评价和可装配件评价，引入并行工程的设计理念，将公差评价方法融入公差优化设计过程，研究了面向三维CAD系统的公差设计和原型系统。     

《表面结构》新标准简介

(一 )国家标准《产品几何量技术规范 (GPS)　表面结构　轮廓法　图形参数》　　国家标准《产品几何量技术规范 (GPS)　表面结构　轮廓法　图形参数》(已报批 )是等效国际标准 ISO1 2 0 85∶ 1 996《产品几何量技术规范 (GPS)　表面结构　轮廓法　图形参数》而在国内首次制订的。该标准适用于宏观和微观几何特性参数的评定 ,是一项产品几何技术规范 (GPS)体系的通用标准。该标准规定了用图形法确定表面结构的有关定义 ,共给出了 1 5条术语定义 ,包括一般定义和参数定义 ,如表面轮廓 ,原始轮廓 ,轮廓的单峰 ,轮廓的单谷 ,图形 ,粗糙度图…     

对GPS国家标准中几何要素的探讨

全国产品尺寸与几何技术规范及检验标准化技术委员会自1999年成立以后，与ISO／TC213相协调，制修订了一批GPS国家标准，使我国基础标准的研究与实践进入了一个新的发展阶段。这些国家标准的发布使标准体系更加完善和合理，必将对我国机械工业的发展产生积极的影响。     

基于GPS的圆柱度公差建模及其规范设计研究

基于GPS的恒定度和恒定类建立了圆柱度公差数学模型;基于所建立的数学模型,采用VB为开发工具在CATIA平台下进行几何变动虚拟仿真模拟,并建立了其肤面模型;基于GPS的操作和算子技术实现了圆柱度公差的规范设计。实验结果表明,基于新一代GPS的产品数字化建模及规范设计是将几何产品的功能要求、规范设计及测量认证进行数字化的统一,体现了并行设计的思想,为GPS的推广应用奠定了一定的基础。     

Measurability invariance,continuity and a portfolio representation

Galileo suggested that what is not measurable be made measurable. It is this principle which underscores an unwritten law of both the sciences and the social sciences that it is better to measure than not to measure. But, the assumption of measurability is rarely considered. In this paper, we consider a set of invariance and continuity conditions which a measure should satisfy. These conditions provide a test of whether a given mapping onto the real line constitutes a measure, and not simply an arbitrary mapping. They represent a test for measurability. In the social sciences, it is common to construct measures based on multi-dimensional attributes. In the paper, we characterise this multi-dimensional measurement as portfolios, with weights determined a priori. Measurement becomes a process of convergence towards a preferred measure which anchors the measurement. Measurement is valid if there is convergence to a measure satisfying the invariance and continuity conditions.     

基于GPS的提取操作模型及其应用规范研究

揭示现代产品几何技术规范(geometrical product specification, GPS)中基于提取方案和提取点数的提取操作模型的构成规律;通过分析提取操作与产品功能特征、结构形状特征以及轮廓谐波成分之间的内在规律,给出面向产品几何特征的数字化设计和计量的基础提取规范;并运用实例阐述该规范在工程实践中的实现方法, 明确提取规范对于实现产品数字化规范设计与计量、丰富并完善ISO及我国现行GPS标准体系是至关重要的.     

一种线结构光视觉传感器标定方法

在线结构光视觉传感器的标定中,结构光光平面上三维世界标定点的获取一直是一个难题。主要是因为靶 标上已知的三维世界点很难恰好位于结构光光平面上。针对这个问题,提出了一种基于双重交比不变的线结构光 视觉传感器的标定方法,设计了相应的标定靶标。利用双重交比不变性,可以获取光平面上任意数量的高精度的 三维标定点,从而解决了线结构光视觉传感器三维标定点不易获取且数量少的问题,提高了线结构光视觉传感器 的标定精度。试验结果表明该方法可以满足大型工件的结构光三维视觉检测精度的要求。     

A new partitioning process for geometrical product specifications and verification

In ISO Geometrical Product Specifications and Verification Standards (GPS), Feature operations are used to obtain ideal and non-ideal features. The formalization of such operations enables to reduce ambiguity and uncertainty within the activities of design, manufacture and metrology of mechanical products, and their scientific investigation contributes to develop a sound mathematical framework and formalisms for the comprehension of engineering practices and the development of new standards. Partitioning is a fundamental operation defined in ISO GPS standard which aims at decomposing a part into independent features or surface portions for further processing and analysis. In this paper, a state-of-the-art survey of partitioning and segmentation methods and techniques reported in the literature is conducted and a comprehensive classification is proposed. Thereafter, a new partitioning process is developed for partitioning into regions and recognizing each region as one of the seven invariance classes of surfaces. It proceeds in three main steps: initial partitioning based on shape index and curvedness, refined partitioning by slippage analysis and invariance class recognition by statistical evaluation. An intuitive shape color wheel is defined to visualize the partitioned features according to their corresponding invariance classes. Experiments and results on both nominal models and measured point clouds are presented to demonstrate the effectiveness of the proposed method.     

Measurement in economic systems

The metrology literature neglects a strong empirical measurement tradition in economics, which is different from the traditions as accounted for by the formalist representational theory of measurement. This empirical tradition comes closest to Mari’s characterization of measurement in which he describes measurement results as informationally adequate to given goals. In economics, one has to deal with soft systems, which induces problems of invariance and of self-awareness. It will be shown that in the empirical economic measurement tradition both problems have been on the agenda for a long while, and that the proposed solutions to these problems provide clues for the directions in which one could develop a measurement theory that takes account of soft systems.     

Quantum Cooperative Robotics and Autonomy

The intersection of Quantum Technologies and Robotics Autonomy is explored in the present paper.The two areas are brought together in establishing an interdisci...     

考虑进油孔有限长滑动轴承油膜力的近似解析解

针对具有进油孔的有限长滑动轴承油膜力求解问题,采用变分原理和分离变量法,求得了有限长滑动轴承油膜压力分布的近似解析表达式。将油膜压力分布的近似解析表达式在油膜存在区域上进行积分,即得到了油膜力。将提出的计算有限长滑动轴承油膜力方法与无限长轴承模型、有限元方法的计算结果进行了比较,发现了提出的方法与有限元方法的计算结果很接近。最后,研究了进油孔位置和进油压力对油膜存在区域、油膜力等的影响,研究结果表明进油孔位置和进油压力对油膜存在区域和油膜力有较大的影响。     

三绕组变压器的双绕组等效建模及在Matpower中的应用

针对实际电网存在着大量的三绕组变压器,但国际上一些著名商业软件,如BPA仿真软件、Matpower这一权威潮流计算开源软件,均只提供双绕组变压器模型,限制了其在具有三绕组变压器的电力系统中的应用的问题,潮流计算是自主开发的电力系统各种应用软件的核心模块,因此依托国际权威开源程序进行二次开发,是一种较好的选择。对Matpower要求的数据格式进行了归纳,对变压器的一般的等值电路及带理想变压器的等值电路和带标幺值的等值电路进行了分析研究,提出了三绕组变压器转换为双绕组等效模型的建模方法,使得原先只适应双绕组变压器的潮流计算软件可以适用于三绕组变压器电网的潮流计算;最后以Matpower软件为例进行了案例计算,并用PSASP仿真软件进行对比验证。研究结果证明,所提出的建模方法是有效的。     

On the Relation of Load to Average Gap in the Contact Between Surfaces with Longitudinal Roughness

A computer simulation model for the contact between longitudinally-oriented rough surfaces has been formulated. This model closely duplicates the actual surf ace contact deformation behavior by taking into account the elastic interactions between the asperities. There were no assumptions made about the shapes, or any deformation behavior of the asperities, except for their obeying the laws of elasticity. The plastic deformations on the high asperity peaks were taken into account by setting a ceiling on their contact pressures at the material hardness value. The simulations used real surface profiles which were digitized from unworn circumferentially ground steel surfaces. Each pair of these profiles was mathematically combined to form an equivalent rough profile pressing against an infinitely rigid flat and having the appropriately adjusted elastic modulus. A total of 28 different pairs of profiles were used in the simulations. Each contacting pair was subjected to 30 different load levels and the local contact pressures and deformations were calculated. The contact simulations yielded some important mathematical relationships between parameters, such as the real area of contact, average gap, and average asperity load through statistical curve fitting. Two analytical functions were generated to relate the average load to average gap and the real area of contact to load.