Improvised Long Test Lengths via Stitching Scale Bar Method: Interim Testing of Laser Trackers

Published

May 28, 2020

Author(s)

Vincent Lee, Daniel S. Sawyer, Balasubramanian Muralikrishnan

Abstract

Performance verifications of laser tracker systems (LTSs) often rely on calibrated length artifacts that are 2.3 m in length or more, as specified in International Standards Organization (ISO) and American Society of Mechanical Engineers (ASME) standards. The 2.3 m length is chosen as the minimum length that will sufficiently expose inaccuracy in LTSs. Embodiment of these artifacts often comes in the form of scale bars, fixed monuments, or a laser rail. In National Institute of Standards and Technology (NIST) Internal Report (IR) 8016, which was published in 2014 and discusses interim testing of LTSs, it was shown that a scale bar with three nests spaced 1.15 m apart was sufficient for exposing errors in LTSs. In that case, the LTS was placed symmetrically with respect to the scale bar so that both a 2.3 m symmetrical length and a 1.15 m asymmetrical length were presented to the LTS. This paper will evaluate whether a scale bar that is only 1.15 m in length can sufficiently expose errors within the LTS when it is stitched together to create a 2.3 m long test length.

Citation

Journal of Research (NIST JRES) -

Volume

125

NIST Pub Series

Journal of Research (NIST JRES)

Pub Type

NIST Pubs

Download Paper

https://doi.org/10.6028/jres.125.016

Local Download

Keywords

interim testing, laser scanners, laser tracker systems, scale bar

Citation

Lee, V. , Sawyer, D. and Muralikrishnan, B. (2020), Improvised Long Test Lengths via Stitching Scale Bar Method: Interim Testing of Laser Trackers, Journal of Research (NIST JRES), National Institute of Standards and Technology, Gaithersburg, MD, [online], https://doi.org/10.6028/jres.125.016 (Accessed March 14, 2025)