Development of deep sea free swimming ROV "UROV7K"

A free-swimming vehicle UROV7K has been developed since 1996. This vehicle is equipped with a high quality and high-speed communication system for wide frequency band devices such like TV cameras, obstacle avoidance sonar and manipulator. An expendable optical fiber cable is used. The cable is one millimeter in diameter and stored in a spooler like a fishing reel. The lithium-ion battery which is rechargeable and immersed in oil, has been developed for this vehicle. Its capacity is 100 V 60 Ah. A big cable store winch, traction winch and high voltage power source are not necessary for this system. The vehicle was able to dive to more than 2000 meters in depth and swim for 90 minutes December 1998. The authors have a plan to dive this vehicle up to 7000 meters in depth July 1999.