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Research paper−95−Synthesiology - English edition Vol.2 No.2 pp.95-106 (Oct. 2009) Y, and Z axes that run at right angles to each other, a scale to measure the distance of transfer, and a computer to control the coordinate transformation and the measuring machine. In the CMM, the range in which the probe (stylus) attached to the probing system can move is its measurement space. It is also possible to calculate not only the distance between two points, but also the feature quantity of geometrical shape of the workpiece (for example, diameter, roundness, and center coordinate of a circle) using the least-square fitting from measured points.Conventionally, CMMs were expensive and required advanced skills to operate, and they were installed only in prototype and quality control divisions of large corporations. However, they are currently installed in manufacturing lines and small factories because of the need to adapt to digital manufacturing, demand for high quality control for products, and for differentiation against products of other Asian countries. By installing the workpiece and building 1 IntroductionJapan became a wealthy country by developing its industry after World War . Particularly, manufacturing, represented by the automobile industry, is the center of Japanese economy. In manufacturing, a product is produced by designing, manufacturing, and assessment. Recently, manufacturing is done using digital data for design, manufacturing, and assessments as shown in Fig. 1. After designing using CAD (computer aided design) and CAE (computer aided engineering), the data is sent to CAM (computer aided manufacturing) for manufacturing. The manufactured product is measured using CAT (computer aided testing), and the measurement data are fed back to the design and manufacturing processes. The analysis and design based on real data as well as the manufacturing process are improved, and this completes the cycle of the manufacturing process. Through the development of the manufacturing system using digital data, it is possible to significantly reduce the days required for manufacturing prototypes. In such digital manufacturing system, coordinate measuring machines (CMM) are often used to assess the shape of the product. CMM is also called the universal measuring machine, and is capable of measuring various three-dimensional shapes (position, size, and geometrical features including straightness, roundness, cylindricity, and squareness).Here, the functions of a CMM will be outlined. As shown in Fig. 2, the CMM consists of a probing system to measure the coordinates by contacting the surface of the workpiece, a guide to linearly transfer the probing system along the X, - Establishment of the traceability system and standardization -Sonko Osawa*, Toshiyuki Takatsuji and Osamu SatoNational Metrology Institute of Japan, AIST Tsukuba Central 3, Umezono 1-1-1, Tsukuba 305-8563, Japan *E-mail : Received original manuscript December 12, 2008, Revisions received January 27, 2009, Accepted May 11, 2009Digital engineering technique has widely been used for speedy and effective manufacturing of industrial products. Coordinate measuring machines (CMM) are being used for measuring three-dimensional shapes of products and taking an important role to keep the quality of the products high. National Metrology Institute of Japan (NMIJ/AIST) has established the traceability system of CMM, that is, measurement results by CMM are traceable to the national standards of length. To achieve this objective, not only calibration techniques have been developed, but industrial standards (ISO and JIS) and guidelines to which accredited laboratories should conform were documented. In addition, to raise the calibration capabilities of prefectural laboratories and to contribute to the local industries, technical supports have been provided by NMIJ.High accuracy three-dimensional shape measurements for supporting manufacturing industriesKeywords : Three-dimensional coordinate measurement, coordinate measuring machine, measurement standard, metrological traceability, digital engineering[Translation from Synthesiology, Vol.2, No.2, p.101-112 (2009)] Measurement dataCirculation of data in digital engineeringDesign dataCAT (measurement, assessment)CAM(processing, manufacturing)CAE(design assistance)CAD(design)Measurement dataDesign dataMeasurementdataProduction of measurement dataProduct made by measurement systemMeasurement for assessmentProduction of processing dataProduct processing by processing machinesFig. 1 Digital data manufacturing.

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