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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.
31

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.
32

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.
33

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.
34

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.
35

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
36

Design of an AUV recharging system / Design of an Autonomous Underwater Vehicle recharging system

Gish, Lynn Andrew January 2004 (has links)
Thesis (Nav. E. and S.M.)--Massachusetts Institute of Technology, Dept. of Ocean Engineering, 2004. / Includes bibliographical references (p. 111-115). / The utility of present Autonomous Underwater Vehicles (AUVs) is limited by their on-board energy storage capability. Research indicates that rechargeable batteries will continue to be the AUV power source of choice for at least the near future. Thus, a need exists in both military and commercial markets for a universal, industry-standard underwater AUV recharge system. A novel solution using a linear coaxial wound transformer (LCWT) inductive coupling mounted on the AUV and a vertical docking cable is investigated. The docking cable may be deployed from either a fixed docking station or a mobile "tanker AUV". A numerical simulation of the simplified system hydrodynamics was created in MATLAB and used to evaluate the mechanical feasibility of the proposed system. The simulation tool calculated cable tension and AUV oscillation subsequent to the docking interaction. A prototype LCWT coupling was built and tested in saltwater to evaluate the power transfer efficiency of the system. The testing indicated that the surrounding medium has little effect on system performance. / (cont.) Finally, an economic analysis was conducted to determine the impact of the proposed system on the present military and commercial AUV markets. The recharge system creates substantial cost-savings, mainly by reducing support ship requirements. An effective AUV recharge system will be an important element of the Navy's net-centric warfare concept, as well as a valuable tool for commercial marine industries. / by Lynn Andrew Gish. / Nav.E.and S.M.
37

Formation control for autonomous marine vehicles

Kleeck, Christopher John Van. January 2009 (has links)
Thesis (M. Sc.)--University of Alberta, 2009. / Title from pdf file main screen (viewed on Dec. 23, 2009). "A thesis submitted to the Faculty of Graduate Studies and Research in partial fulfillment of the requirements for the degree of Master of Science, Department of Mechanical Engineering, University of Alberta." Includes bibliographical references.
38

Unifying behavior based control design and hybrid stability theory for AUV application /

Djapic, Vladimir. January 2009 (has links)
Thesis (Ph. D.)--University of California, Riverside, 2009. / Includes abstract. Title from first page of PDF file (viewed January 28, 2010). Available via ProQuest Digital Dissertations. Includes bibliographical references (p. 149-153).
39

Experiments with the REMUS AUV /

Phaneuf, Matthew D. January 2004 (has links) (PDF)
Thesis (M.S. in Mechanical Engineering)--Naval Postgraduate School, June 2004. / Thesis advisor(s): Anthony J. Healey. Includes bibliographical references (p. 57-59). Also available online.
40

Horizontal steering control in docking the ARIES AUV /

Tan, Wee Kiat. January 2003 (has links) (PDF)
Thesis (M.S. in Mechanical Engineering)--Naval Postgraduate School, December 2003. / Thesis advisor(s): Fotis Papoulias, Anthony J. Healey. Includes bibliographical references (p. 83). Also available online.

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