Physical Sciences and Mathematics Commons^™

Self Consistent Bathymetric Mapping Using Sub-Maps: Survey Results From The Tag Hydrothermal Structure, C. Roman, R. Reves-Sohn, H. Singh, S. Humphris

Christopher N. Roman

The spatial resolution of microbathymetry maps created using robotic vehicles such as ROVs, AUVs and manned submersibles in the deep ocean is currently limited by the accuracy of the vehicle navigation data. Errors in the vehicle position estimate commonly exceed the ranging errors of the acoustic mapping sensor itself, which creates inconsistency in the map making process and produces artifacts that lower resolution and distort map integrity. We present a methodology for producing self-consistent maps and improving vehicle position estimation by exploiting accurate local navigation and utilizing terrain relative measurements. The complete map is broken down into individual "sub-maps'', which …

High-Resolution Sonar Surveying: Techniques And Strategies For Improved Micro-Bathymetic Mapping, Vicki Ferrini, D. Fornari, T. Shank, D. Kelley, M. Tivey, S. Carbotte, D. Glickson, C. Roman, A. Sterling

Christopher N. Roman

No abstract provided.

Improved Vehicle Based Multibeam Bathymetry Using Sub-Maps And Slam, Christopher Roman, Hanumant Singh

Christopher N. Roman

This paper presents an algorithm to improve sub-sea acoustic multibeam bottom mapping based on the simultaneous mapping and localization (SLAM) methodology. Multibeam bathymetry from underwater water vehicles can yield valuable large scale terrain maps of the sea door, but the overall accuracy of these maps is typically limited by the accuracy of the vehicle position estimates. The solution presented here uses small bathymetric patches created over short time scales in a sub-mapping context. These patches are registered with respect to one another and assembled in a single coordinate frame to produce a more accurate terrain estimate and provide improved renavigation …

Exploring The Persistence Of Sorted Bedforms On The Inner-Shelf Of Wrightsville Beach, North Carolina, Benjamin Gutierez, George Voulgaris, Robert Thieler

George Voulgaris

Geological studies offshore of Wrightsville Beach, North Carolina reveal subtle large-scale regions of coarse sand with gravel and shell hash (widths between 100 and 200 m and negative relief of ∼1 m) that trend obliquely to the coast. It was previously suggested that these regions serve as conduits for sand exchange between the shoreface and inner shelf during storm-associated downwelling. Consequently they were classified as rippled scour depressions. More recently, the role of alongshore flows and self-organization as a result of inhibited settling of fine sand has been discussed. In this study, 45 days of near-bed current measurements were analyzed …

Effect Of Channel Bifurcation On Residual Estuarine Circulation: Winyah Bay, South Carolina, Yong Kim, George Voulgaris

George Voulgaris

The residual circulation pattern of Winyah Bay, the fourth largest estuary on the eastern coast of the US, is examined using stationary and shipborne current measurements during periods of low freshwater discharge. The estuary has a complex morphology with a single channel and narrow banks at the river entrance and the bay mouth, and a bifurcated channel system (main and western channels, respectively) in the middle part that appears to affect the residual circulation. Overall, the upper (single channel morphology) and middle (dual-channel morphology) parts of the estuary exhibit a baroclinic residual circulation. The presence of bifurcated channels in the …

Sustainable Development And Natural Governance: The Challenges Ahead, John Dernbach, Dan Tarlock

John C. Dernbach

No abstract provided.

Targets, Timetables And Effective Implementing Mechanisms: Necessary Building Blocks For Sustainable Development, John C. Dernbach

John C. Dernbach

No abstract provided.

Advances In High Resolution Imaging From Underwater Vehicles, Hanumant Singh, Christopher Roman, Oscar Pizarro, Ryan Eustice

Christopher N. Roman

Large area mapping at high resolution underwater continues to be constrained by the mismatch between available navigation as compared to sensor accuracy. In this paper we present advances that exploit consistency and redundancy within local sensor measurements to build high resolution optical and acoustic maps that are a consistent representation of the environment.

We present our work in the context of real world data acquired using Autonomous Underwater Vehicles (AUVs) and Remotely Operated Vehicles (ROVs) working in diverse applications including shallow water coral reef surveys with the Seabed AUV, a forensic survey of the RMS Titanic in the North Atlantic …