The solar-powered autonomous underwater vehicle (SAUV) was designed for long-endurance missions, such as monitoring, surveillance, or station-keeping, where real-time bidirectional communications to shore are critical. In April 2006, the Naval Undersea Warfare Center (NUWC) Division Newport, Falmouth Scientific Inc. (FSI), and Autonomous Undersea Systems Institute (AUSI) conducted a 30-day, long-endurance test using SAUV II primarily to demonstrate that the vehicle is capable of conducting long-term oceanographic data collection and to validate the vehicle's mechanical integrity. This test also served to evaluate possible anomalies and risk-reduction measures for future production-level vehicles. A key part of this long-endurance test was the logging of the SAUV II charge and discharge rates under different sky and weather conditions with the vehicle under varied energy load situations-data that can be used to assess vehicle endurance and help establish future mission capabilities of the SAUV II. This paper describes the SAUV II test vehicle, test methods, data collected, and the results of the long-endurance test.
Three examples of inter-agency cooperation utilizing current generation, individual Autonomous Underwater Vehicles (AUVs) are described consistent with recent recommendations of the U.S. Commission on Ocean Policy. The first steps in transforming individual AUVs into adaptive, networked systems are underway. To realize an affordable and deployable system, a network-class AUV must be designed with cost–size constraints not necessarily applied in developing solo AUVs. Vehicle types are suggested based on function and ocean operating regime: surface layer, interior and bottom layer. Implications for platform, navigation and control subsystems are explored and practical formulations for autonomy and intelligence are postulated for comparing performance and judging behavior. Laws and conventions governing intelligent maritime navigation are reviewed and an autonomous controller with conventional collision avoidance behavior is described. Network-class cost constraints can be achieved through economies of scale. Productivity and efficiency in AUV manufacturing will increase if constructive competition is maintained. Constructive strategies include interface and operating standards. Professional societies and industry trade groups have a leadership role to play in establishing public, open standards.
Loadout of the 24,000 ton Auger deck and the subsequent open ocean joining of the deck to the 20,000 ton floating hull (hereafter referred to as the mating operation), posed interesting technical and operational challenges. The knowledge gained through technical analyses was incorporated into detailed procedures which led to both operations being successful. Some of the actual responses varied from the theoretical solutions, but remained acceptable. Introduction The deck was 1oaded onto McDermott's Intermac 650 material barge in the transverse direction which meant that large loads needed to be transferred over relatively short distances. This led to the development of an allowable displacement "envelope". This envelope related the land based deck elevation(s) to the floating material barge elevation. A barge ballast plan, a straightforward dimensional control plan to measure the actual displacements, a program to process the surveying information and formalized channels of communication were all included in the detailed procedure. These procedures were used to monitor the operation and ensured that the actual relative vertical displacements were within the tight tolerances of an allowable "envelope". The deck was mated to the floating hull in 240 feet of water in the unprotected Gulf of Mexico during hurricane season. Many analyses were performed to verify the acceptability of the mating concept and to detail the actual operations plan. The motions of both components were studied to ensure that adequate cent rolled separation between the two floating bodies would occur; thus, preventing damage to the deck, hull and the material barge. Hydraulic cylinders were selected as the control led release mechanism in lieu of using explosives which was the original proposal. Temporary ballast, power and mooring systems were developed for the hull to make the operation efficient and secure. Detailed offshore procedure manuals were developed which described the deck, hull and barge(s) preparations; on-site positioning of the marine spread consisting of the hull and two attendant derrick barges; a step by step rigging plan for the actual float-in; ballast operations and mooring system operations and severe weather contingency planning due to hurricanes. Loadout Analyses: Models and Techniques The deck was fabricated by McDermott Incorporated in Amelia, Louisiana and was erected on top of a temporary support frame referred to as the cribbage. The 985 ton cribbage was approximately 32 feet high and provided the proper elevation for mating. The cribbage was a space frame consisting of four main truss rows which supported the main truss rows of the deck. The cribbage was supported by four, pile supported, land based skidways. Four mooring dolphins were installed in the canal to support the skidways extending into the canal. To maintain the proper elevation during loadout, the canal needed to be deepened. Since bringing the barge up against the bulkhead would have required dredging at the bulkhead, thereby compromising its integrity, the Contractor chose the option of using mooring dolphins in the quay as opposed to reconstructing the bulkheads.
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