Title: Versatile calibration artefact for optical micro-CMMs based on micro-spheres with engineered surface texture
Authors: Thalmann, Rudolf, Federal Institute of Metrology METAS, Bern-Wabern, Switzerland
Küng, Alain, Federal Institute of Metrology METAS, Bern-Wabern, Switzerland
Nicolet, Anaïs, Federal Institute of Metrology METAS, Bern-Wabern, Switzerland
Meli, Felix, Federal Institute of Metrology METAS, Bern-Wabern, Switzerland, ORCID: 0000-0001-7575-7540
Battagli, Christoph, NTB Interstaatliche Hochschule für Technik Buchs, Institut PWO, Buchs, Switzerland

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Contributors: HostingInstitution: Physikalisch-Technische Bundesanstalt (PTB), ISNI: 0000 0001 2186 1887
Resource Type: Text / Article
Publisher: Physikalisch-Technische Bundesanstalt (PTB)
Rights: https://creativecommons.org/licenses/by/4.0/
CC BY 4.0
Dates: Available: 2018-03-28
Created: 2017-12-21
File: Download File (application/pdf) 523.55 kB (536115 Bytes)
MD5 Checksum: 59a218c7d55cee07a59b87ff23e910bd
SHA256 Checksum: ed4da8e7f9ed94d16d2ceaef47acddf757bcbe1512c6d61684ef045f77a1d243
Keywords optical micro-CMM ; micro-sphere ; calibration artefact
Abstract: For the calibration and performance verification of optical micro coordinate measuring machines we have developed an artefact which is based on small spherical elements with optically cooperative surfaces. It is in fact a three-dimensional ball plate with a number of different micro-spheres arranged on an amphitheatre-like glass substrate. The micro-spheres were produced with an adequate quality in terms of roughness and sphericity and an engineered surface texture, which is optically cooperative and thus suitable for optical sensors based on focus variation, chromatic, confocal or astigmatic sensor principles. The application of the calibration artefact allows to evaluate instrument parameters such as volumetric length measurement errors, calibration factors of the three axes separately, orthogonality errors between all three axes, alignment errors of the optical sensor with respect to the instrument axes, as well as scale and form errors of the optical sensor.
Other: This article is based on a presentation at the conference "MacroScale 2017 - Recent developments in traceable dimensional measurements", VTT MIKES Espoo, (Finnland), 17th-19th October 2017.