Abstract
Arctic circulation drives multi-year sea ice against the Canadian Arctic Archepelago, making this margin one of the toughest regions in the Arctic Ocean to survey. Yet Canada had a need to map the seafloor in this region as part of its Extended Continental Shelf Program. One of the solutions to this challenge that Canada adopted was to develop an Autonomous Underwater vehicle that is mobile, could operate under the ice to 5000 m water depth, acquire bathymetric data and return to a location that is unknown prior to mission programming. A partnership program between Natural Resources Canada, Canadian Hydrographic Services, Defense Research Development Canada and International Submarine Engineering Inc.was launched to develop a vehicle that could be operated from an ice camp, work under ice, return to the drifting ice camp, and dump data and recharge while still in the water. The AUV was outfitted with a Knudsen 118 kHz single beam echosounder and a Kongsberg-Simrad EM2000 (200 kHz) multibeam sonar system. In 2010, the first trial of the under-ice AUV was undertaken. The system was launched near Borden Island of the Canadian Arctic Archipelago 400 km under the ice to be recovered at a drifting ice camp. It maintained a height of approximately 100 m above the seafloor and acquired single beam bathymetric data during its voyage. It was recharged at a remote camp and sent back to its base camp acquiring data on its return voyage. In 2011, the system was launched and recovered from an ice-breaker. It traveled 110 km under ice and acquired multibeam data along its track, travelling over difficult terrain during it's transect of a feature known as Sever Spur. The surface ship had drifted about 10 km from its deployment position during the mission, but the AUV was able to return within metres of the vessel.
