Open AccessFlexible method of refraction correction in vision measurement systems with multiple glass ports
Author(s) -
Zheng Gong,
Zhen Liu,
Guangjun Zhang
Publication year - 2017
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.25.000831
Subject(s) - refraction , optics , perpendicular , computer science , orientation (vector space) , port (circuit theory) , machine vision , rectification , atmospheric refraction , computer vision , engineering , physics , mechanical engineering , mathematics , geometry , electrical engineering , voltage
Many vision measurement systems, especially in outdoor engineering, usually utilize glass ports to protect sensors against environmental influences. The refraction caused by glass ports lead to measurement errors in traditional single viewpoint model. Most existing methods only deal with the refraction that happens once, and the glass ports are required to be perpendicular to cameras or the orientations of glass ports are obtained by auxiliary equipment. This paper proposes a corrected 3D reconstruction model based on refraction geometry, which can be used for any number of glass ports with any orientations. The orientation of each glass port is obtained only using refracted and unrefracted images of the same scene, which doesn't need any auxiliary equipment. A series of validation experiments are performed. An existing image rectification method is used to make a comparison. The proposed method is also employed in a train wheelset profile measurement application, which proves that the method is effective in actual applications.