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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
51

The development and deployment of a submersible ROV for the underwater inspection of hydroelectric station tunnels /

Heffron, Ronald E., January 1990 (has links)
Project report (M. Eng.)--Virginia Polytechnic Institute and State University, 1990. / Vita. Abstract. Includes bibliographical references (leaf 104). Also available via the Internet.
52

Autonomous underwater vehicles (AUV) sensitivity of motion response to geometric and hydrodynamic parameters and AUV behaviours with control plane faults /

Perrault, Douglas Edward, January 2002 (has links)
Thesis (Ph.D.)--Memorial University of Newfoundland, 2002. / Bibliography: leaves 212-222.
53

A minefield reconnaissance simulation /

Guedes, Mauricio Jose Machado. January 2002 (has links) (PDF)
Thesis (M.S. in Operations Analysis)--Naval Postgraduate School, June 2002. / "June 2002." Thesis advisor(s): Alan R. Washburn. Includes bibliographical references (p. 39). Also available online.
54

Real-time sonar classification for autonomous underwater vehicles

Campbell, Michael Scott. January 1996 (has links) (PDF)
Thesis (M.S. in Computer Science and M.S. in Electrical Engineering) Naval Postgraduate School, March 1996. / Thesis advisor(s): D.P. Brutzman, Xiaoping Yun. "March 1996." Includes bibliographical references (p. 55-56). Also available online.
55

Autonomous control of underwater vehicles and local area maneuvering

Marco, David Bryan. January 1996 (has links) (PDF)
Dissertation (Ph. D. in Mechanical Engineering) Naval Postgraduate School, September 1996. / Dissertation supervisor(s): Anthony Healey. "September 1996." Includes bibliographical references (p. 341-345). Also available online.
56

Using discrete event simulation to assess obstacle location accuracy in the REMUS unmanned underwater vehicle

Allen, Timothy E. 06 1900 (has links)
is shown to follow an exponential distribution. These three models enable operators to explore the impact of various inputs prior to programming the vehicle, thus allowing them to choose the best combination of vehicle parameters that minimize the offset error between the reported and actual locations.
57

Undersea navigation via a distributed acoustic communications network

Hahn, Matthew J. 06 1900 (has links)
Acoustic modems are the basis for emerging undersea wireless communications networks. US Navy Seaweb technology offers an opportunity to perform undersea navigation and tracking by virtue of node-to-node ranging measurements acquired as a by-product of the acoustic communications protocol. A simple localization algorithm is developed and verified with synthetic data and is then tested with an Unmanned Undersea Vehicle (UUV) during an experiment at sea.
58

Stability analysis of a towed body for shipboard unmanned surface vehicle recovery

Roberts, Scott D. 03 1900 (has links)
As the U.S. Navy develops new technologies which enhance automation and reduce crew size onboard naval vessels, unmanned vehicles will become increasingly valuable in conducting maritime operations. Effective launch and recovery systems (LARS) are necessary for unmanned vehicles to efficiently conduct operations at sea. The Towed Body system is a LARS with a wide range of applications for unmanned vehicle operations. The Towed Body can be evaluated as a small vessel with horizontal and vertical control surfaces. Since it is being towed, the directional stability of the Towed Body requires unique consideration due to the presence of the towing force. This thesis examines the effect of varying the longitudinal location of the vertical control surfaces, as well as the effective aspect ratio, size, and number of vertical control surfaces. The results identify critical stability values for the various fin configurations.
59

Design and analysis of side-looking sonar experiments

Tsaprazis, Konstantinos 12 1900 (has links)
This research concerns the design and analysis of different Side-Looking Sonar experiments in order to satisfy different operational requirements. The different designs and analysis have been done via computer simulation. Side-Looking Sonar (also known as side-scan sonar) is known for very high quality, high resolution, ocean bottom imaging. Hence, it is used for bathymetric surveys, commonly called seafloor mapping. It is able to rapidly survey large ocean areas for bottom and suspended sea-mines or other kinds of threats. Another operational aspect of these systems is that they allow autonomous underwater vehicles (AUVs) to conduct operations, mostly in shallow water and near land. Thus Side-Looking Sonar can be a very useful device in littoral warfare operations. This research has defined the basic parameters that rule the operation of a Side-Looking Sonar and, furthermore, analyzed various aspects that affect the performance of these parameters. Special focus was given to the various operational requirements and conditions that a designer or a user may encounter in realistic situations. Toward that end, many numerical examples are presented. Moreover, the research has tried to indicate the various problems that may arise when a Side-Looking Sonar operates in its near-field region and suggests certain solutions. The active sonar equation and its factors were explained and were evaluated for a realistic example of mine detection as well.
60

Autopilot using differential thrust for ARIES autonomous underwater vehicle

Sarton, Christopher J. 06 1900 (has links)
Approved for public release; distribution is unlimited / Future underwater missions will require data transmission via satellite. In particular, the Office of Naval Research (ONR) is interested in experimenting with communications using the GOES satellite system, which is government owned. Unfortunately, communication antennas must point to specific satellites in this system and thus underwater vehicles must steer a specific course on the surface during the communication process. While surfaced, underwater vehicles are subject to wind and wave disturbances and it has been suggested that control using differential thrust from propellers may provide advantages. This thesis covers efforts to create and test such a steering autopilot based on the use of the ARIES AUV and differing the voltage supplied to each propeller. It is planned to use the ARIES in an ocean experiment to test this satellite communication capability. This control is embedded in the control of ARIES during extended pop up maneuvers for GPS navigational fixes. When surfaced, not only are navigational fixes obtained, but also data packets are communicated to a command center. / Lieutenant, United States Navy

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