This page is meant to be a storehouse for publications that reflect activities of interest to AUVAC and its members. If you have publications that should be added to this list please let us know and we will include them.

All About Batteries

December 4, 2013 via - EE Times

There are lots of factors to consider when choosing the battery technology for a particular application. In addition to relative size, weight, and cost (from cheap to expensive to "if you have to ask, you can't afford it"), the main considerations and factors I plan on covering in this series are as follows:

Environment (operating and storage): Temperature, air pressure, altitude, mechanical strain, vibration, mounting position, radiation hardening, corrosive attack, packaging/shape, storage or shelf life, disposal, waste products produced and outgassing, consumables required, safety, and materials/RoHS

Application: Types (including primary, secondary, and smart), technology, chemistries, efficiency and loss, charge/discharge cycle count and rates, depth of discharge, service life, memory effect, charging techniques, capacitor/battery hybrid, use cases, capacity, density (energy and weight), protection circuitry, measuring and gas gauge, quality, reliability, and recharge and run times

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Hovering Type AUV “Tuna-Sand” and Its Surveys on Smith Caldera in Izu-Ogasawara Ocean Area

September 25, 2013 via -

Abstract—During the operation of and AUV in the ocean, it is necessary to monitor the vehicles position and the status in real time to prevent accidents that may occur abrupt changes in oceanic condition. Therefore a support ship should follow and monitor the AUV during survey. The ship operation costs are high and it is inefficient use if only one AUV dives during a survey. We developed a new survey method for multiple AUVs to make effective use of ship time. In our survey method, two cruising AUVs (AE2000a and AE2000f) pass through approximately the same route and observe the seafloor at a high altitude. One hovering type AUV (Tuna-Sand) navigates and takes pictures of seafloor at a low altitude. The ship follows the two cruising AUVs and sends the command by acoustic communication as necessary. Then an SSBL device on a moored buoy localizes Tuna-Sand and sends vehicle’s position and status
to the ship by satellite communications. To avoid sound wave interference, sufficient time gap is added between signal
transmissions and the GPS time is used for synchronization. The Tuna-Sand AUV observed on Smith caldera in Izu-Ogasawara ocean area in two dives using our survey method. In first dive, the vehicle surveyed for about 2 hours and took 170 pictures of the seafloor. In second dive, we succeeded that AE2000a, AE2000f and Tuna-Sand dived and surveyed on the caldera at same time. The results obtained during the survey are described in detail in this paper.

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DARPA BAA 13-39 (Hydra)

August 22, 2013 via - DARPA

The Hydra program will develop and demonstrate an unmanned undersea system, providing a novel delivery mechanism for insertion of unmanned air and underwater vehicles into operational environments. Situated underwater, Hydra will use modular payloads within a standardized enclosure to enable scalable, cost-effective deployment of rapid response assets and will integrate existing and emerging technologies in new ways to create an alternate means of delivering a variety of payloads close to the point of use. The Hydra program seeks to develop
and demonstrate initial examples of air and undersea payloads while leaving open the potential for accommodating additional payloads in the future.

The rising number of ungoverned states, piracy, and proliferation of sophisticated defenses severely stretches current resources and impacts the nation’s ability to conduct special operations and contingency missions. The Hydra program represents a cost effective way to add undersea capacity that can be tailored to support each mission. Hydra’s communications suite could allow synergistic function with manned platforms, thus increasing their effectiveness, or
could allow remote control from over-the-horizon. Technologies are intended to be adaptable to multiple delivery options, including airborne, surface, and subsurface. The Hydra program will enable other new capabilities not currently performed from undersea.

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