Reconstruction of Refractive Index Maps Using Photogrammetry

A. Miller, A. J. Mulholland, K. M. M. Tant, S. G. Pierce, A. B. Forbes, B. Hughes

Research output: Contribution to journalArticle (Academic Journal)peer-review

2 Citations (Scopus)
111 Downloads (Pure)

Abstract

Large volume metrology is a key component of autonomous precision manufacturing. Photogrammetry systems are an example of an optical-based metrology system and can be used for component positioning.However,these positional measurements are subject to uncertainties which can be greater than manufacturing tolerances. In large scale industrial environments the uncertainties due to thermal gradients which cause refraction of the light rays, need to be considered. This paper uses light-based sensor data to reconstruct the heterogeneous spatial map of the refractive index in the air. This is then used to discount the refractive effects and thereby reduce the uncertainty of this positioning problem. This new inverse problem employs Voronoi tessellations to spatially parameterise the refractive index map, the forward problem of calculating the light rays through this medium is solved using the Fast Marching Method, and a Bayesian approach is then used as the optimisation method in the inversion. Using simulated data, the recovered refractive index map leads to positioning improvements of up to 37 %.
Original languageEnglish
Pages (from-to)2696-2718
Number of pages23
JournalInverse Problems in Science and Engineering
Volume29
Issue number13
Early online date1 Jul 2021
DOIs
Publication statusE-pub ahead of print - 1 Jul 2021

Bibliographical note

Funding Information:
This work was funded by a studentship with the University of Strathclyde in collaboration with the National Physical Laboratory (NPL), London, UK.

Publisher Copyright:
© 2021 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group.

Research Groups and Themes

  • Engineering Mathematics Research Group

Keywords

  • photogrammetry
  • metrology
  • refractive index
  • reversible jump Markov Chain Monte Carlo
  • Fast Marching Method
  • Voronoi tessellations

Fingerprint

Dive into the research topics of 'Reconstruction of Refractive Index Maps Using Photogrammetry'. Together they form a unique fingerprint.

Cite this