The Unmanned Untethered Submersible Technology (UUST) conferences are held the third week in August to convene the best and the brightest in the AUV development field to exchange ideas and formulas for improving technologies. "It's all about pushing the envelope in terms of applications and capabilities," said Dick Blidberg, the event's organizer and Director of the Autonomous Undersea Systems Institute (AUSI). This summer's August 20-23 event was no exception. There is a loyal, global following of individuals that attend the three-day event, which prides itself, thanks to Blidberg's laid-back style, to a no-tie policy. (In the past, some attendees wearing ties have had them removed!) Set in the trees in Durham, NH, at the New England Center at UNH, one can concentrate fully on what the future holds for AUVs. The conference this summer offered no less than 65 technical sessions, a handful of sponsor booths and many impressive attendees. The Portsmouth Yacht Club kick-off event featuring heavy appetizers and margaritas set the stage for a friendly, low key atmosphere. Lunches were superb networking opportunities as was the ample lobster and clam feast on the second evening. Over the years the UUST has provided a forum for many new ideas and technologies to be heard. During the presentations there is a lot of feedback from the attendees, which include a veritable 'who's who' of AUV developers, users, manufacturers and funding agencies. Areas of critical concern that continually require refinement include topics such as communication to and from the AUV both underwater and topside; navigation and control of the vehicles once they are underway; issues relating to how to operate a fleet of AUVs in unison; and the continued development of quiet propulsion systems such as gliders and vehicles that move like fish, turtles or lobsters. Reference the proceedings to obtain details on all presentations. Just a few of the presentations are highlighted here to offer a glimpse of what to expect from the AUV development community. One of the AUSI board members, a former Navy program manager, mentioned that glider technologies such as Webb Research Corporation's Slocum glider are filling an important gap. The Slocum glider is an autonomous underwater vehicle that creates its forward propulsion by varying vehicle buoyancy. Wings and control surfaces convert vertical force into forward velocity so that it glides downward when denser than water, and glides upward when buoyant. The vehicle traces a sawtooth profile, observing temperature and conductivity versus depth,
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and, at the surface, it can transmit its exact GPS position via satellite communication. Because gliders have no propellers or machine driven motors, they are very quiet and can operate for long periods. At programmed intervals they surface, upload data and their position and return to their preprogrammed mission. Clayton Jones of Webb Research Corporation reported on the collaboration with Rutgers University over the past two years to improve the Slocum class glider by adding a 1,000 m depth variant to the existing 200 m version and by integrating new sensor payloads. The Rutgers team exercised Slocum's deployment strategies during tests off the New Jersey coast and other worldwide locations, including Antarctica. In so doing they learned a lot about fast turn around times, data management and adaptive fleet control. According to the conference proceedings, as of July 2007, Rutgers has flown more than 115 missions flying over 32,000 km, resulting in 925 calendar days in the water. The data set achieved is over one quarter of a million profiles. In addition they were successful at flying six separate Slocum gliders in a coordinated fleet. All vehicles communicated via Iridium satellite to a Dockserver housed in a control station at the university. At prescribed intervals the vehicles surfaced to upload mission data as well as their position. That information was overlaid with the transmissions of other vehicles in the fleet and each vehicle could in turn receive new mission parameters to fill in the modeling inputs required by the forecast system. Through various funding mechanisms and forums such as this event and the AUV Fest, the U.S. Navy can seed many new developments to test the use of AUVs for anti submarine and littoral battlespace operations. According to Thomas Swean, Program Manager at the Office of Naval Research, "a fleet of AUVS and gliders working together can map an area near a submarine and feed that information back real time". AUVs and gliders are presenting new ways of directing subs and ships through the oceans of the world. Eventually these vehicles can be deployed from a sub or a ship and they can fan out and profile large areas. The data they gather can be included in predictive models that can be handed back to fleet operations for fleet management. During AUV Fest in Panama City, Fla., this past spring, three Solar Autonomous Underwater Vehicles (SAUV) surveyed an area together. Steven Chappell of AUSI reported on his work that culminated in the demonstration in Florida to develop a better interface that would enable vehicles to send each other signals and take indeMarine Technology Reporter 39
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