Conclusion

The importance of providing vertical correctors for AUV multibeam data and the fact that traditional shore-based gauges may not be available underscore the need for this VTC calculation technique. Additionally, this technique will allow for rapid in-field assessment of data both internally and with respect to data from surface platforms. When provided with precise inputs, it offers a favorable alternative to both the high uncertainty of predicted tidal correctors and the strict collection requirements of traditional tidal data. When the vessel collecting EH data lacks a motion sensor and thus requires estimation of the height of the GNSS antenna above the

waterline, the uncertainty achieved by the technique is too large for the resultant VTC data to be used for hydrographic survey. If, however, the vessel attitude is an input to the system,

uncertainty can be managed sufficiently to allow for those data to provide vertical corrections for AUV hydrographic data.

Precise measurement of all input parameters as well as proper mathematical manipulation of the VTC series must be achieved in order to minimize uncertainty. Modifications to this technique could result in a VTC series that more accurately represents the shape of the corresponding conventional tide curve, but the technique as it was described in this thesis is sufficient to provide vertical correction to IHO Order 1 AUV multibeam data. Future testing is required to isolate systematic inaccuracies, to refine the mathematical manipulation of the VTC data, to minimize input uncertainties, and to quantify the spatial limits of the method.

44

References

Bracewell, Ronald N. The Fourier Transform and Its Applications. 3rd ed. New York: McGraw-

Hill Science/Engineering/Math, 1999. Print.

Brennan, Richard, Kurt Hess, Lloyd Huff, and Steve Gill. “The Design of an Uncertainty Model for the Tidal Constituent and Residual Interpolation (TCARI) Method for Tidal

Correction of Bathymetric Data.” Paper accepted for publication in the proceedings of U.S. Hydro 2005, March 29-31, 2005. San Diego, California. Web. February 10, 2015. Byrne, Shannon, Walter Simmons, Gail Smith, and Bill Mehaffey. “A Demonstration of GPS

Based Vertical Control, Unaided by a Shore Station.” Presentation of Shallow Survey 2008, October 21-24, 2008, Portsmouth, New Hampshire. Web. February 10, 2015. Diebel, James. “Representing Attitude: Euler Angles, Unit Quaternions, and Rotation Vectors.”

2006. Stanford, California: Stanford University. Web. July 17, 2015.

Dodd, Dave, Jerry Mills, Dean Battilana, and Michael Gourley. “Hydrographic Surveying Using

the Ellipsoid as the Vertical Reference Surface.” Facing the Challenges—Building the

Capacity: Proceedings of FIG Congress 2010. April 11-16, 2010, Sydney, Austrialia. Web. February 10, 2015.

Dodd, Dave and Jerry Mills. “Ellipsoidally Referenced Surveys (ERS); Issues and Solutions.” Paper accepted for publication in the proceedings of U.S. Hydro 2011, April 25-28, 2011. Tampa, FL. Web. December 10, 2014.

Forbes, Steve, Phillip MacAulay, Chris Coolen, and Fred Carmichael. “A Laser-Based Water Level Sensor and Robust Insulated and Heated Multi-Well Stilling Well System for Ice- Prone Temperate and Sub-Arctic Environments.” Presentation of U.S. Hydro 2009, May 11 – 14, 2009, Norfolk, Virginia. Web. April 8, 2015.

Gao, Yang. “GNSS Solutions: Precise Point Positioning and Its Challenges, Aided-GNSS and

Signal Tracking.” InsideGNSS, November/December 2006. Web. September 3, 2015.

Hiller, Thomas, Arnar Steingrimsson, and Robert Melvin. “Positioning Small AUVs for Deeper

Water Surveys Using Inverted USBL.” Taking Care of the Sea:Proceedings of Hydro12.

November 12-15, 2012, Rotterdam, the Netherlands. Rotterdam: Hydrographic Society of Benelux, 2012. Print.

International Hydrographic Organization Special Publication No. 44. IHO Standards for

Hydrographic Surveys, 5th Ed. International Hydrographic Bureau. Monaco, 2008. Web. February 13, 2015.

Ku, H. H. “Notes on the Use of Propagation of Error Formulas.” Journal of Research of the

National Bureau of Standards—C. Engineering and Instrumentation. 70C.4 (1966): (263- 273). Web. August 14, 2015.

45

National Oceanic and Atmospheric Administration Special Publication NOS CO-OPS 1. Tidal

Datums and Their Applications. Edited by Stephen K. Gill and John R. Schultz. February

2001. Web. August 11, 2015.

Press, William, Saul Teukolsky, William Vetterling, and Brian P. Flannery. Numerical Recipes

in C. Cambridge, United Kingdom: Cambridge University Press, 1997. Print.

Rice, Glen and Jack Riley. “Measuring the Water Level Relative to the Ellipsoid During

Hydrographic Survey.” Paper accepted for publication in the proceedings of U.S. Hydro 2011, April 25-28, 2011. Tampa, FL. Web. July 5, 2015.

Riley, Jack and Bryan Murray. “GPS Water Level Buoy Uncertainty Case Study.” Paper accepted for publication in the proceedings of U.S. Hydro 2015, March 16-19, 2011. National Harbor, MD. Web. July 4, 2015.

Weisstein, Eric W. “Nyquist Frequency.” From MathWorld—A Wolfram Web Resource. http://mathworld.wolfram.com/RotationMatrix.html.

Weisstein, Eric W. “Rotation Matrix.” From MathWorld—A Wolfram Web Resource. http://mathworld.wolfram.com/RotationMatrix.html.

Wert, Travis D. Tidal Height Retrieval Using Globally Corrected GPS in the Amundsen Gulf

Region of the Canadian Arctic. MS thesis. The University of New Bruswick, Fredericton, Canada. 2004. Web. August 14, 2015.

46

Vita

The author was born in Picayune, Mississippi. After attending Picayune Memorial High School, he earned his bachelor of science in physics from The University of Alabama in 2008. He began his career with the Federal Government at Naval Oceanographic Office in 2009 where he currently investigates the problems of hydrographic survey and their solutions. He began his study of applied physics at The University of New Orleans in 2009.