Large Scale Metrology
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Dimensional measurement traceability of 3D imaging data – S. Phillips, M. Krystek, C. Shakarji, K. Summerhays.
Abstract This paper discusses the concept of metrological traceability to the International System of Units (SI) unit of length, the meter. We describe how metrological traceability is realized, give a recent example of the standardization of laser trackers, and discuss progress and challenges to the traceability of 3D imaging data.
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Error mapping of CMMs and machine tools by a single tracking interferometer – H. Schwenke, M. Franke, and J. Hannaford.
Abstract This paper presents a novel approach for the mapping of geometric errors of machine tools and coordinate measuring machines by a single tracking interferometer. The concept is based on interferometric displacement measurements between reference points that are fixed to the base and offset points fixed to the machine head. The experimental comparison with an…
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A practical method for evaluating measurement system uncertainty – JM. Calkins, and RJ. Salerno.
Abstract This paper describes a procedure used to determine the measurement uncertainties of spherical measurement systems. This procedure requires measuring a series of unknown yet fixed points from several different instrument locations. The resulting observations are then bundled to determine the set of instrument locations that minimizes the observational discrepancies of the system. We shall…
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Whole-viewing-angle cat’s-eye retroreflector as a target of laser trackers – T. Takatsuji, M. Goto, S. Osawa, R. Yin and T. Kurosawa.
Abstract A spherical cat’s-eye retroreflector made from a glass material having a refractive index of two was developed. The geometrical sphericity of the cat’s eye and the sphericity examined optically were approximately 100 nm and 500 nm respectively. The discrepancy between these two values is discussed. This optical device is very versatile in terms of…
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Advances in large-scale metrology–review and future trends – R.H. Schmitt et al.
Abstract The field of Large-Scale Metrology has been studied extensively for many decades and represents the combination and competition of topics as diverse as geodesy and laboratory calibration. A primary reason that Large-Scale Metrology continues to represent the research frontier is that technological advances introduced and perfected at a conventional scale face additional challenges which…
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Robot performance measurements using automatic laser tracking techniques – K. Lau K, R. Hocken, L. Haynes.
Laser tracker/5 Abstract This paper describes two laser tracking techniques currently under development at the National Bureau of Standards for robot performance measurements. Tests indicate that the system can be used in real-time to determine the three-dimensional static and dynamic positioning accuracy of a robot end-effector to a few parts in 100,000 (i.e. 12.5–50 μm…
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Choosing test positions for laser tracker evaluation and future standards development – B. Muralikrishnan, D Sawyer, C. Blackburn, S.Phillips, C. Shakarji, and E.Morse .
Laser Tracker/4 Abstract A working group within the ISO TC 213 committee is developing a draft document [1] for evaluating the performance of laser trackers. The ASME B89. 4.19 Standard [2] and the draft VDI/VDE 2617 part 10 [3] describe some useful tests that are incorporated into this new ISO document. But both the ASME…
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Large-scale metrology instrument performance evaluations at NIST- WT Estler, D. Sawyer, B. Borchardt, S.D. Phillips.
Laser Tracker/3 Abstract The ASME B89 Committee on Dimensional Metrology has approved a new American National Standard B89.4.19 – Performance Evaluation of Laser Based Spherical Coordinate Measurement Systems. This Standard, to be published in 2006, specifies test methods for traceable calibrations of laser trackers for the measurement of point-to-point length. NIST has completed a dedicated…
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ASME B89.4.19 performance evaluation tests and geometric misalignments in laser trackers – B. Muralikrishnan, D. Sawyer, C. Blackburn, S. Phillips, B. Borchardt B, T.Estler.
Laser Tracker/2 ABstract Small and unintended offsets, tilts, and eccentricity of the mechanical and optical components in laser trackers introduce systematic errors in the measured spherical coordinates (angles and range readings) and possibly in the calculated lengths of reference artifacts. It is desirable that the tests described in the ASME B89.4.19 Standard [1] be sensitive…
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Laser trackers for large-scale dimensional metrology: A review – B. Muralikrishnan, S. Phillips , D. Sawyer
Laser Tracker/1 Abstract Thirty years since their invention, laser trackers are now recognized as the measurement tool of choice in the manufacture and assembly of large components. The general design of laser trackers, i.e., a ranging unit on a two-axis gimbal, has not changed significantly over the years. However, innovations in ranging technology, for example,…
