Autonomous Underwater Vehicle “Tuna-Sand” for Image Observation of the Seafloor at a Low Altitude

AUV Tuna-Sand An autonomous underwater vehicle Tuna-Sand operating at a depth of 1,500 m to investigate benthic organisms was developed to observe detailed images of the seafloor. Once submerged, vehicle Tuna-Sand navigates several meters altitude above the seafloor with complex terrain using only onboard sensors and taking 2,000 high-resolution images of the seafloor before returning to the surface. Since its launch in March 2007, vehicle Tuna-Sand has performed underwater research 81 times in Japan’s exclusive economic zone, e.g., Kagoshima Bay, the Myojinsho caldera, and the Kuroshima knoll as of March 2014. Survey on the Joetsu knoll in the waters off of Niigata in July 2010 clarified the presence of live red snow crabs – a confirmation highly appreciated by fisheries researchers. An image-based photomosaic showed that 3,341 red snow crabs lived on the Joetsu knoll within an area of 800 m 2 . The authors are planning to survey the biomass of Kichiji rockfish in the Kitami-Yamato sea bank.