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  • 1
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    Wiley
    In:  Journal of Field Robotics, 24 (1-2). pp. 23-50.
    Publication Date: 2017-08-10
    Description: The achievable accuracy of bathymetric mapping in the deep ocean using robotic systems is most often limited by the available guidance or navigation information used to combine the measured sonar ranges during the map making process. This paper presents an algorithm designed to mitigate the affects of poor ground referenced navigation by applying the principles of map registration and pose filtering commonly used in simultaneous localization and mapping (SLAM) algorithms. The goal of the algorithm is to produce a self-consistent point cloud representation of the bottom terrain with errors that are on a scale similar to the sonar range resolution rather than any direct positioning measurement. The presented algorithm operates causally and utilizes sensor data that are common to instrumented underwater robotic vehicles used for mapping and scientific explorations. Real world results are shown for data taken on several expeditions with the JASON remotely operated vehicle (ROV). Comparisons are made between more standard mapping approaches and the proposed method is shown to significantly improve the map quality and reveal scene information that would have otherwise been obscured due to poor direct navigation information.
    Type: Article , PeerReviewed
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  • 2
    Publication Date: 2019-09-23
    Type: Article , PeerReviewed
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  • 3
    Publication Date: 2019-09-23
    Description: Highlights • Marine Image Annotation Software (MIAS) are used to assist annotation of underwater imagery. • We compare 23 MIAS assisting human annotation including some that include automated annotation. • MIAS can run in real time (50%), allow posterior annotation (95%), and interact with databases and data flows (44%). • MIAS differ in data input/output and display, customization, image analysis and re-annotation. • We provide important considerations when selecting UIAS, and outline future trends. Abstract Given the need to describe, analyze and index large quantities of marine imagery data for exploration and monitoring activities, a range of specialized image annotation tools have been developed worldwide. Image annotation - the process of transposing objects or events represented in a video or still image to the semantic level, may involve human interactions and computer-assisted solutions. Marine image annotation software (MIAS) have enabled over 500 publications to date. We review the functioning, application trends and developments, by comparing general and advanced features of 23 different tools utilized in underwater image analysis. MIAS requiring human input are basically a graphical user interface, with a video player or image browser that recognizes a specific time code or image code, allowing to log events in a time-stamped (and/or geo-referenced) manner. MIAS differ from similar software by the capability of integrating data associated to video collection, the most simple being the position coordinates of the video recording platform. MIAS have three main characteristics: annotating events in real time, in posteriorly to annotation and interact with a database. These range from simple annotation interfaces, to full onboard data management systems, with a variety of toolboxes. Advanced packages allow to input and display of data from multiple sensors or multiple annotators via intranet or internet. Posterior human-mediated annotation often include tools for data display and image analysis, e.g. length, area, image segmentation, point count; and in a few cases the possibility of browsing and editing previous dive logs or to analyze annotation data. The interaction with a database allows the automatic integration of annotations from different surveys, repeated annotation and collaborative annotation of shared datasets, browsing and querying of data. Progress in the field of automated annotation is mostly in post processing, for stable platforms or still images. Integration into available MIAS is currently limited to semi-automated processes of pixel recognition through computer-vision modules that compile expert-based knowledge. Important topics aiding the choice of a specific software are outlined, the ideal software is discussed and future trends are presented.
    Type: Article , PeerReviewed
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  • 4
    Publication Date: 2022-05-25
    Description: Author Posting. © The Authors, 2005. This is the author's version of the work. It is posted here by permission of Elsevier B. V. for personal use, not for redistribution. The definitive version was published in Continental Shelf Research 26 (2006): 194-205, doi:10.1016/j.csr.2005.10.004.
    Description: The benthic communities of the deep insular shelf at the Hind Bank Marine Conservation District (MCD), an important spawning grouper aggregation site, were studied with the Seabed autonomous underwater vehicle (AUV) at depths between 32 to 54 m. Four digital phototransects provided data on benthic species composition and abundance of the insular shelf off St. Thomas, U.S. Virgin Islands. Within the western side of the MCD, well developed coral reefs with 43% mean living coral cover were found. The Montastrea annularis complex was dominant at all four sites between 33 to 47 m, the depth range where reefs were present. Maximum coral cover found was 70% at depths of 38 to 40 m. Quantitative determinations of sessile-benthic populations, as well as the presence of motile-megabenthic invertebrates and algae were obtained. The Seabed AUV provided new quantitative and descriptive information of a unique coral reef habitat found within this deeper insular shelf area.
    Description: Funding was provided in part by the CenSSIS ERC of the National Science Foundation under grant EEC-9986821 and by the Caribbean Fishery Management Council. University of the Virgin Islands staff time was supported by a grant from Sea Grant (R-101-1-02) to R. Nemeth.
    Keywords: Atlantic ; U.S. Virgin Islands ; Coral reef ; Deep hermatypic corals ; AUV
    Repository Name: Woods Hole Open Access Server
    Type: Preprint
    Format: 907575 bytes
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  • 5
    Publication Date: 2022-05-25
    Description: Author Posting. © The Author(s), 2008. This is the author's version of the work. It is posted here by permission of John Wiley & Sons for personal use, not for redistribution. The definitive version was published in Journal of Field Robotics 25 (2008): 861-879, doi:10.1002/rob.20250.
    Description: The recent Arctic GAkkel Vents Expedition (AGAVE) to the Arctic Ocean’s Gakkel Ridge (July/August 2007) aboard the Swedish ice-breaker I/B Oden employed autonomous underwater vehicles (AUVs) for water-column and ocean bottom surveys. These surveys were unique among AUV operations to date in requiring georeferenced navigation in proximity to the seafloor beneath permanent and moving ice cover. We report results for long-baseline (LBL) acoustic navigation during autonomous under-ice surveys near the seafloor and adaptation of the LBL concept for several typical operational situations including navigation in proximity to the ship during vehicle recoveries. Fixed seafloor transponders were free-fall deployed from the ship for deep positioning. The ship’s helicopter collected acoustic travel times from several locations to geo-reference the transponders’ locations, subject to the availability of openings in the ice. Two shallow beacons suspended from the ship provided near-surface spherical navigation in ship-relative coordinates. During routine recoveries, we used this system to navigate the vehicles into open water near the ship before commanding them to surface. In cases where a vehicle was impaired, its position was still determined acoustically through some combination of its acoustic modem, the fixed seafloor transponders, the ship-deployed transponders, and an on-board backup relay transponder. The techniques employed included ranging adapted for a moving origin and hyperbolic navigation.
    Description: Major funding for AGAVE was provided by the National Science Foundation (PP-0425838, ATM- 0428122), the National Aeronautics and Space Administration (Z601701), and the Woods Hole Oceanographic Institution.
    Repository Name: Woods Hole Open Access Server
    Type: Preprint
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  • 6
    Publication Date: 2022-05-25
    Description: Author Posting. © Oceanography Society, 2007. This article is posted here by permission of Oceanography Society for personal use, not for redistribution. The definitive version was published in Oceanography 20, 4 (2007): 140-149.
    Description: In deep water, below the photic zone, still and video imaging of the seabed requires artificial lighting. Light absorption and backscatter caused by typical seawater components, such as dissolved organic matter, plankton, and inorganic particles, often limit the artificially lit area to a few square meters. To obtain high-resolution photographic data of larger seabed areas, a series of images can be compiled into a photo mosaic. Image mosaics are easier to interpret, communicate, and exhibit than video footage or a series of images, because the individual image frames in a photo mosaic are naturally represented in a spatial context.
    Repository Name: Woods Hole Open Access Server
    Type: Article
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  • 7
    Publication Date: 2022-05-25
    Description: Author Posting. © The Author(s), 2009. This is the author's version of the work. It is posted here by permission of Elsevier B.V. for personal use, not for redistribution. The definitive version was published in Deep Sea Research Part I: Oceanographic Research Papers 56 (2009): 2065-2074, doi:10.1016/j.dsr.2009.06.008.
    Description: Numerous attempts have been made over the last thirty years to estimate fluid flow rates at hydrothermal vents, either at the exit of black smoker chimneys or within diffuse flow areas. In this study, we combine two methods to accurately estimate fluid flow velocities at diffuse flow areas. While the first method uses a hot film anemometer that performs high frequency measurements, the second allows a relatively rapid assessment of fluid flow velocity through video imagery and provides in situ data to calibrate the sensor. Measurements of flow velocities on hydrothermal diffuse flow areas were obtained on the Mid-Atlantic Ridge (MAR). They range from 1.1 to 4.9 mm/sec., at the substratum level, in low temperature (4.5 to 16.4°C) diffuse flow areas from the Tour Eiffel sulfide edifice. A strong correlation was observed between fluid flow velocities and temperature, supporting the possible use of temperature as a proxy to estimate flow rates in diffuse flow areas where such a simple linear flow/temperature relation is shown to dominate.
    Description: The first part of this research was sponsored by a NOAA/NURP grant award #NA96RU0221 and NSF grant OCE-9901563 to MKT and JS. JS was also supported by a FCAR (Quebec) post-doctoral fellowship. The last part of the project was supported through the ANR DEEP OASES (ANR06 BDV005).
    Keywords: Fluid flow velocity ; Hydrothermal vent ; Hot film anemometer ; Video imagery ; Diffuse flow
    Repository Name: Woods Hole Open Access Server
    Type: Preprint
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  • 8
    Publication Date: 2022-05-25
    Description: © The Author(s), 2016. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in PeerJ 4 (2016): e1770, doi:10.7717/peerj.1770.
    Description: A research cruise to Hannibal Bank, a seamount and an ecological hotspot in the coastal eastern tropical Pacific Ocean off Panama, explored the zonation, biodiversity, and the ecological processes that contribute to the seamount’s elevated biomass. Here we describe the spatial structure of a benthic anomuran red crab population, using submarine video and autonomous underwater vehicle (AUV) photographs. High density aggregations and a swarm of red crabs were associated with a dense turbid layer 4–10 m above the bottom. The high density aggregations were constrained to 355–385 m water depth over the Northwest flank of the seamount, although the crabs also occurred at lower densities in shallower waters (∼280 m) and in another location of the seamount. The crab aggregations occurred in hypoxic water, with oxygen levels of 0.04 ml/l. Barcoding of Hannibal red crabs, and pelagic red crabs sampled in a mass stranding event in 2015 at a beach in San Diego, California, USA, revealed that the Panamanian and the Californian crabs are likely the same species, Pleuroncodes planipes, and these findings represent an extension of the southern endrange of this species. Measurements along a 1.6 km transect revealed three high density aggregations, with the highest density up to 78 crabs/m2, and that the crabs were patchily distributed. Crab density peaked in the middle of the patch, a density structure similar to that of swarming insects.
    Description: This work was sponsored by a grant from the Dalio Foundation, Inc, through the Woods Hole Oceanographic Institution.
    Keywords: Swarms ; Ecological hotspot ; Patchiness ; Panama ; Eastern Pacific ; Seamount ; Pleuroncodes planipes ; Hypoxic environment ; Anomuran crabs
    Repository Name: Woods Hole Open Access Server
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  • 9
    Publication Date: 2022-05-25
    Description: Recent advances in underwater robotics and imaging technology now enable the rapid acquisition of large datasets of near-bottom high-resolution digital imagery. These images provide the potential for developing a non-invasive technique for fisheries data acquisition that reveals the organisms in their natural habitat and can be used to identify important habitat characteristics. Using these large datasets effectively, however, requires the development of computer-based techniques that increase the efficiency of data analysis. This document describes one such tool, FISH_ROCK, which was developed for a group of fisheries researchers using the SeaBED AUV during a research cruise in October 2005. FISH_ROCK is a graphical user interface (GUI) that is executed within Matlab, and allows users digitally generate a database that includes organism identification, quantity, size and distribution as well as details about their habitat. Further development of this GUI will enable its use in different oceanographic environments including the deep sea, and will include modules that perform data analysis.
    Description: Funding was provided by the National Oceanic and Atmospheric Administration under Grant No. AB133F05SE5828.
    Keywords: Benthic organisms ; Bottom photographs ; Database
    Repository Name: Woods Hole Open Access Server
    Type: Technical Report
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  • 10
    Publication Date: 2022-05-25
    Description: Author Posting. © IEEE, 2006. This article is posted here by permission of IEEE for personal use, not for redistribution. The definitive version was published in IEEE Transactions on Robotics 22 (2006): 1110-1114, doi:10.1109/TRO.2006.886264.
    Description: This paper reports the novel insight that the simultaneous localization and mapping (SLAM) information matrix is exactly sparse in a delayed-state framework. Such a framework is used in view-based representations of the environment that rely upon scan-matching raw sensor data to obtain virtual observations of robot motion with respect to a place it has previously been. The exact sparseness of the delayed-state information matrix is in contrast to other recent feature-based SLAM information algorithms, such as sparse extended information filter or thin junction-tree filter, since these methods have to make approximations in order to force the feature-based SLAM information matrix to be sparse. The benefit of the exact sparsity of the delayed-state framework is that it allows one to take advantage of the information space parameterization without incurring any sparse approximation error. Therefore, it can produce equivalent results to the full-covariance solution. The approach is validated experimentally using monocular imagery for two datasets: a test-tank experiment with ground truth, and a remotely operated vehicle survey of the RMS Titanic.
    Keywords: Information filters ; Kalman filtering ; Machine vision ; Mobile robot motion planning ; Mobile robots ; Recursive estimation ; Robot vision systems ; Simultaneous localization and mapping ; Underwater vehicles
    Repository Name: Woods Hole Open Access Server
    Type: Article
    Format: 1299688 bytes
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