As the Navy continues its development of unmanned underwater vehicles, the need for total autonomous missions grows. Autonomous Underwater Vehicles (AUV) allow for advances in mine warfare, harbor reconnaissance, undersea warfare and more. Information can be collected from AUVs and downloaded into a ship or battle group.s network. As AUVs are developed it is clear forward-look sonar will be required to be able to detect obstacles in front of its search path. Common obstacles in the littoral environment include reefs and seawalls which an AUV will need to rise above to pass. This thesis examines the behavior and control system required for an AUV to maneuver over an obstacle in the vertical plane. Hydrodynamic modeling of a REMUS vehicle enables a series of equations of motion to be developed to be used in conjunction with a sliding mode controller to control the elevation of the AUV. A two-dimensional, 24o vertical scan forward look sonar with a range of 100 m is modeled for obstacle detection. Sonar mappings from geographic range-bearing coordinates are developed for use in MATLAB simulations. The sonar .image. of the vertical obstacle allows for an increasing altitude command that forces the AUV to pass safely over the obstacles at a reasonable rate of ascent and pitch angle. Once the AUV has passed over the obstacle, the vehicle returns to its regular search altitude. This controller is simulated over different types of obstacles. / US Navy (USN) author.

Thesis (M.Sc.)--York University, 2008. Graduate Programme in Science. / Typescript. Includes bibliographical references (leaves 156-160). Also available on the Internet. MODE OF ACCESS via web browser by entering the following URL: http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&res_dat=xri:pqdiss&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft_dat=xri:pqdiss:MR45937

Thesis (M.S.)--Naval Postgraduate School, 2002. / Thesis advisor(s): Anthony J. Healey. Includes bibliographical references (p. 99-101). Also available online.

Thesis (M.S. in Mechanical Engineering)--Naval Postgraduate School, September 2003. / Thesis advisor(s): Anthony J. Healey. Includes bibliographical references (p. 45). Also available online.

Thesis (MScIng)--University of Stellenbosch, 2008. / Bibliography. Also available via the Internet.

Thesis (Mechanical Engineer and M.S. in Mechanical Engineering)--Naval Postgraduate School, December 2002. / Thesis advisor(s): Anthony J. Healey. Includes bibliographical references (p. 67-68). Also available online.

Thesis (M.Sc.Eng.)-University of KwaZulu-Natal, Durban, 2010. / Full text also available online. Scroll down for electronic link.

Thesis (M.Eng.)--Memorial University of Newfoundland, 2001. / Bibliography: leaves 93-98.

CIVINS / Approved for public release; distribution is unlimited / 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. 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. / Lieutenant Commander, United States Navy

In the interest of enhancing the capabilities of autonomous underwater vehicles US Naval Operations, controlling vehicle position to follow depth contours presents exciting potential for navigation. Use of a contour tracking control algorithm in lieu of preprogrammed waypoint navigation offers distinct advantages within new challenges. The difficult nature of this problem lies in the non-trivial connection between the necessary corrective action and the feedback error used in traditional control methods. Stated simply, modern vehicle control algorithms separate horizontal and vertical plane navigation. The autonomous vehicle senses heading error and applies rudder to steer the vehicle to a desired heading. Simultaneously, the vehicle might sense altitude and apply stern plane angles to maintain a safe height above ground. This thesis research examines the new problem of sensing depth and altitude in the vertical plane while steering the vehicle horizontally to find a specified bathymetry contour. While more remains to understand, this research proves the existence of a solution and suggests similar approaches may facilitate tying vehicle navigation to other indirect sensors. This thesis presents two contour tracking control algorithms and examines the performance of each by simulating the response of the REMUS underwater vehicle to ideal and real-world bathymetry models.