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An underwater glider is a type of autonomous underwater vehicle (AUV) that uses small changes in its buoyancy in conjunction with wings to convert vertical motion to horizontal, and thereby propel itself forward with very low power consumption. While not as fast as conventional AUVs, gliders using buoyancy-based propulsion represent a significant increase in range and duration compared to vehicles propelled by electric motor-driven propellers, extending ocean sampling missions from hours to weeks or months, and to thousands of kilometers of range. Gliders follow an up-and-down, sawtooth-like profile through the water, providing data on temporal and spatial scales unavailable to previous AUVs, and much more costly to sample using traditional shipboard techniques.〔 A wide variety of glider designs are in use by Navy and ocean research organizations and typically cost $100,000 (USD) == History == The DARPA SBIR program received a proposal for a temperature gradient glider in 1988. DARPA was aware at that time of similar research projects underway in the USSR.〔(【引用サイトリンク】title=Perpetual Autonomus Survey Submersible )〕 The concept of an underwater glider was first explored in the early 1960s with a prototype swimmer delivery vehicle named Concept Whisper.〔 The sawtooth glide pattern, stealth properties and the idea of a buoyancy engine powered by the swimmer-passenger was described by Ewan Fallon in his Hydroglider patent submitted in 1960. In 1992, the University of Tokyo conducted tests on ALBAC, a drop weight glider with no buoyancy control and only one glide cycle.〔 The idea of a glider with a buoyancy engine powered by a heat exchanger was introduced to the oceanographic community by Henry Stommel in a 1989 article in ''Oceanography'', when he proposed a glider concept called ''Slocum'', developed with research engineer Doug Webb. They named the glider after Joshua Slocum, who made the first solo circumnavigation of the globe by sailboat. They proposed harnessing energy from the thermal gradient between deep ocean water (2-4 °C) and surface water (near atmospheric temperature) to achieve globe-circling range, constrained only by battery power on board for communications, sensors, and navigational computers. By 2005, not only had a working thermal-powered glider (''Slocum Thermal'') been demonstrated by Webb Research (founded by Doug Webb), but they and other institutions had introduced battery-powered gliders with impressive duration and efficiency, far exceeding that of traditional survey-class AUVs. The University of Washington ''Seaglider'' and Scripps Institution of Oceanography ''Spray'' vehicles have performed feats such as crossing the Gulf Stream from the mainland USA to Bermuda, and, together with the Webb ''Slocum'', conducting sustained, multi-vehicle collaborative monitoring of oceanographic variables in Monterey Bay. In 2011, the first wingless glider, ''SeaExplorer'' was released with a large payload capacity, dedicating the first third of the vehicle to interchangeable payloads, in addition to typical CTD sensors. The vehicle achieves 1 knot speeds, is equipped with externally rechargeable Li-Ion batteries and its torpedo shape is able to glide relying on two pairs of small static rear fins for stability. Originally conceived as testbed for the thermal-power gliders before developing into a platform of their own, the Webb Slocum electric gliders have been widely deployed since 2003. On December 4, 2009, one of these gliders, RU-27, became the first to complete a transatlantic journey, traveling from New Jersey to the coast of Spain in 221 days.〔Kirk Moore, "Rutgers undersea glider makes trans-Atlantic crossing," Daily Record, December 6, 2009 ()〕 The effort was led by a team from Rutgers University, which has become one of the largest glider operators. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Underwater glider」の詳細全文を読む スポンサード リンク
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