Abstract

Abstract. This paper will describe a novel approach for the calibration of an underwater laser triangulation system. Underwater triangulation systems, consisting of a line laser and a camera can be used to determine the geometry of submerged objects or the topography of a water body bottom. Placing camera and laser line projector inside a waterproof housing leads to refraction effects at the air-glass-water interfaces, both of the laser light-sheet and image rays. This implies a deformed laser plane in the water and a curved line on the object surface. The proposed approach strictly models the geometry between camera, laser and housing. First experiments show, that the calibration method can be applied for water depth measurements with accuracies of 0.2–0.3 mm at depths in the order of 100 mm.

Highlights

  • This paper will describe a novel approach for the calibration of an underwater laser triangulation system

  • A triangulation system consisting of a line laser and a camera is used for underwater depth measurement

  • For validation of the calibration procedure, a triangulation system, consisting of a green laser and an industrial camera has been placed in a glass housing

Read more

Summary

Introduction

This paper will describe a novel approach for the calibration of an underwater laser triangulation system. Placing camera and laser line projector inside a waterproof housing leads to refraction effects at the air-glass-water interfaces, both of the laser light-sheet and image rays. This implies a deformed laser plane in the water and a curved line on the object surface. When laser triangulation is used in underwater environments, there are two main adaptions necessary: First, because of the increasing opaqueness of water for higher wavelengths (Hale and Querry, 1973), a green or blue laser is usually chosen Both the laser plane and the image rays are refracted at the air-housing and housing-water interfaces. The approach proposed in this paper considers rotation of the laser around all axes

Methods
Results
Conclusion

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.