Development and preliminary assessment of an optical wave gauge

Gregory Payne, Jean Richon, David M. Ingram, J. Spinneken

Research output: Chapter in Book/Report/Conference proceedingChapter

Abstract

A description and preliminary results are presented for a non-intrusive optical wave gauge based on the principle of optical triangulation. In the proposed implementation, a LASER source beaming vertically downwards generates a spot of scattered light at the water surface. The spot is imaged by an off-axis video camera, and instantaneous wave height measurements are obtained by
processing of the spot images. The spot position on the image is then transformed into a height value using a polynomial best-fit function established by an initial calibration. The gauge geometry is set to give a measurement range of 300mm. The calibration method and apparatus are described. A detailed statistical analysis of the calibration results is presented both for the optical wave gauge and for a conductivity wave gauge used as a
comparison. Dynamic measurements for regular waves of 25mm and 50mm amplitudes at 1Hz are carried out with both probes. The resulting time series data are compared to a theoretical fifth order Stokes solution. While
overall agreement is good for both types of probe, optical wave gauge data are found to provide a better fit to the theoretical solution, especially in the vicinity of wave crests
Original languageEnglish
Title of host publicationProceedings of the 8th European Wave and Tidal Energy Conference
Subtitle of host publicationEWTEC 2009: Uppsala, Sweden, 7-10 September 2009
Place of PublicationUppsala, Sweden
Publication statusPublished - 2009
Event8th European Wave and Tidal Energy Conference, EWTEC 2009 - Uppsala, Sweden
Duration: 7 Sep 200910 Sep 2009

Conference

Conference8th European Wave and Tidal Energy Conference, EWTEC 2009
CityUppsala, Sweden
Period7/09/0910/09/09

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Gages
Calibration
Video cameras
Triangulation
Time series
Statistical methods
Polynomials
Geometry
Water

Cite this

Payne, G., Richon, J., Ingram, D. M., & Spinneken, J. (2009). Development and preliminary assessment of an optical wave gauge. In Proceedings of the 8th European Wave and Tidal Energy Conference: EWTEC 2009: Uppsala, Sweden, 7-10 September 2009 Uppsala, Sweden.
Payne, Gregory ; Richon, Jean ; Ingram, David M. ; Spinneken, J. / Development and preliminary assessment of an optical wave gauge. Proceedings of the 8th European Wave and Tidal Energy Conference: EWTEC 2009: Uppsala, Sweden, 7-10 September 2009. Uppsala, Sweden, 2009.
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Payne, G, Richon, J, Ingram, DM & Spinneken, J 2009, Development and preliminary assessment of an optical wave gauge. in Proceedings of the 8th European Wave and Tidal Energy Conference: EWTEC 2009: Uppsala, Sweden, 7-10 September 2009. Uppsala, Sweden, 8th European Wave and Tidal Energy Conference, EWTEC 2009, Uppsala, Sweden, 7/09/09.

Development and preliminary assessment of an optical wave gauge. / Payne, Gregory; Richon, Jean; Ingram, David M.; Spinneken, J.

Proceedings of the 8th European Wave and Tidal Energy Conference: EWTEC 2009: Uppsala, Sweden, 7-10 September 2009. Uppsala, Sweden, 2009.

Research output: Chapter in Book/Report/Conference proceedingChapter

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M3 - Chapter

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Payne G, Richon J, Ingram DM, Spinneken J. Development and preliminary assessment of an optical wave gauge. In Proceedings of the 8th European Wave and Tidal Energy Conference: EWTEC 2009: Uppsala, Sweden, 7-10 September 2009. Uppsala, Sweden. 2009