< back to main site

Publications

Standards for testing freeform measurement capability of optical and tactile co-ordinate measuring machines.

Acko, B*; McCarthy, M; Haertig, F*; Buchmeister, B* (2012) Standards for testing freeform measurement capability of optical and tactile co-ordinate measuring machines. Meas. Sci. Technol., 23 (9). 094013

Full text not available from this repository.

Abstract

Abstract. For decades three¿dimensional (3D) measurements of engineering components have been made using fixed metrology-room based coordinate measuring machines (CMMs) fitted most commonly with single point or to a much lesser extent, scanning tactile probes. Over the past decade there has been a rapid uptake in development and subsequent use of portable optical-based 3D coordinate measuring systems. These optical based systems capture vast quantities of point data in a very short time, often permitting freeform surfaces to be digitised. Documented standards, for example like ISO10360, for the verification of fixed CMMs fitted with tactile probes are now widely available, whereas verification procedures and more specifically verification artifacts for optical-based systems are still in their infancy. Furthermore, industry is seeking traceability in 3D measurements of high precision components. A recent requirement is the demand for highly accurate measurements of large gears with diameters up to 1000 mm used in gear boxes of wind turbines. Up until now it has been impossible to assure traceability of 3D measurements of big gears, since no traceable standards were available. This paper describes three different types of artifact that were developed during the project, namely tetrahedron artifacts for testing basic measurement capability of optical 3D devices, freeform verification artifacts for testing capability of measuring complex geometry, and a large gear artifact for task related calibration of different types of CMMs. In addition, artifact calibration data and associated measurement uncertainties and international intercomparisons are presented. These developments will be of considerable value to end users, calibration laboratories and producers of optical and tactile CMMs.

Item Type: Article
Keywords: traceability, co-ordinate measuring machine, freeform, 3D artifact, performance test, gear standard, scanning
Subjects: Engineering Measurements
Engineering Measurements > Dimensional
Identification number/DOI: 10.1088/0957-0233/23/9/094013
Last Modified: 02 Feb 2018 13:14
URI: http://eprintspublications.npl.co.uk/id/eprint/5529

Actions (login required)

View Item View Item