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A Camera Intrinsic Matrix-Free Calibration Method for Laser Triangulation Sensor Chen, Xuzhan; Chen, Youping; Chen, Bing; He, Zhuo; Ma, Yunxiu; Zhang, Dailin; Najjaran, Homayoun; Najjaran, Homayoun

Abstract

Laser triangulation sensors (LTS) are widely used to acquire depth information in industrial applications. However, the parameters of the components, e.g., the camera, of the off-the-shelf LTS are typically unknown. This makes it difficult to recalibrate the degenerated LTS devices during regular maintenance operations. In this paper, a novel one-dimensional target-based camera intrinsic matrix-free LTS calibration method is proposed. In contrast to conventional methods that calibrate the LTS based on the precise camera intrinsic matrix, we formulate the LTS calibration as an optimization problem taking all parameters of the LTS into account, simultaneously. In this way, many pairs of the camera intrinsic matrix and the equation of the laser plane can be solved and different pairs of parameters are equivalent for displacement measurement. A closed-form solution of the position of the one-dimensional target is proposed to make the parameters of the LTS optimizable. The results of simulations and experiments show that the proposed method can calibrate the LTS without knowing the camera intrinsic matrix. In addition, the proposed approach significantly improves the displacement measurement precision of the LTS after calibration. In conclusion, the proposed method proved that the precise camera intrinsic matrix is not the necessary condition for LTS displacement measurement.

Item Metadata

Title
A Camera Intrinsic Matrix-Free Calibration Method for Laser Triangulation Sensor
Creator
Chen, Xuzhan; Chen, Youping; Chen, Bing; He, Zhuo; Ma, Yunxiu; Zhang, Dailin; Najjaran, Homayoun; Najjaran, Homayoun
Publisher
Multidisciplinary Digital Publishing Institute
Date Issued
2021-01-14
Description
Laser triangulation sensors (LTS) are widely used to acquire depth information in industrial applications. However, the parameters of the components, e.g., the camera, of the off-the-shelf LTS are typically unknown. This makes it difficult to recalibrate the degenerated LTS devices during regular maintenance operations. In this paper, a novel one-dimensional target-based camera intrinsic matrix-free LTS calibration method is proposed. In contrast to conventional methods that calibrate the LTS based on the precise camera intrinsic matrix, we formulate the LTS calibration as an optimization problem taking all parameters of the LTS into account, simultaneously. In this way, many pairs of the camera intrinsic matrix and the equation of the laser plane can be solved and different pairs of parameters are equivalent for displacement measurement. A closed-form solution of the position of the one-dimensional target is proposed to make the parameters of the LTS optimizable. The results of simulations and experiments show that the proposed method can calibrate the LTS without knowing the camera intrinsic matrix. In addition, the proposed approach significantly improves the displacement measurement precision of the LTS after calibration. In conclusion, the proposed method proved that the precise camera intrinsic matrix is not the necessary condition for LTS displacement measurement.
Subject
calibration; laser triangular sensor; one-dimensional target
Genre
Article
Type
Text
Language
eng
Date Available
2021-01-25
Provider
Vancouver : University of British Columbia Library
Rights
CC BY 4.0
DOI
10.14288/1.0395694
URI
http://hdl.handle.net/2429/77167
Affiliation
Applied Science, Faculty of; Non UBC; Engineering, School of (Okanagan)
Citation
Sensors 21 (2): 559 (2021)
Publisher DOI
10.3390/s21020559
Peer Review Status
Reviewed
Scholarly Level
Faculty
Rights URI
https://creativecommons.org/licenses/by/4.0/
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DSpace

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CC BY 4.0