Presentation: Observation of Deep Seafloors by Autonomous Underwater Vehicles.
Biographical Information: Tamaki Ura is Director and Professor of Underwater Technology Research Center at the Institute of Industrial Science (IIS) of the University of Tokyo, and Director of the Tokyo University Ocean Alliance, since its establishment in 2007. He is one of the top-leaders of development of Autonomous Underwater Vehicle in the world. He has developed not only Autonomous Underwater Vehicles (AUVs) but also various related application technologies including navigation methods, a new sensing method using a chemical sensor, precise seafloor mapping methods, a precise seabed positioning system with a resolution of a few centimeters, a new sensing system of the thickness of cobalt-rich crust, etc. Finally, he exemplified using these technologies that AUVs are practicable and valuable tools for deep-sea exploration.
Not only for the academic fields but also for the public, he has been contributing to the Ocean related themes. He was a Commissioned Judge of the High Marine Accidents Inquiry Agency from 1984 to 2008, and he was the chairman of the Ocean Technology Committee of the Society of Naval Architects of Japan from 1998 to 2000 as well. Based on these activities, he has received many awards. Most recently, he has been recognized with the IEEE Oceanic Engineering Society Distinguished Technical Achievement Award (USA) (2010); Nominated as IEEE Fellow, for contributions to autonomous underwater vehicle technologies. (USA) (2007), and the Distinguished Service Award from IEEE Japan Chapter (Japan) (2006).
The AUV (Autonomous Underwater Vehicle) is a dynamically stable platform that can be used for automatic, high-resolution visual and/or acoustic observation of deep seafloors. The following three examples illustrate the advantages of observation using AUVs and give some idea of the scope of applications. The AUV “Tri-Dog 1” has annually visited the tube worm fields in Kagoshima bay since 2006, and has taken pictures of colonies of shallow water (about 100m depth) tube worms (Lamellibrachia satsuma). A mosaic based on these pictures was superimposed on a detailed 3D configuration of the seafloor. The second example is based on dives by the AUV “Tuna-Sand” in July 2010. The AUV performed twelve dives over gas-hydrate fields in Toyama bay and took about 7,000 pictures from an altitude of 2.2 meters above the floor at a depth of 1,000 meters. One of the mosaics shows 3,500 snow crabs (Chionoecetes japonicas) in a 40 meters by 20 meters area. The third example is exploration of the Izena caldron carried out by the AUV “r2D4” in November 2008. The AUV succeeded in taking side scan SONAR (SSS) images, which show several small hydro-thermal mounds and chimneys at the base of the Izena caldron at a depth of 1,600 meters. Based on the SSS images and bathymetry map measured by the interferometry SONAR, JOGMEC (Japan Oil, Gas and Metals National Corporation) selected suitable locations to perform drilling in order to survey the amount of mineral deposits at the site.