Sea trial of AUV "URASHIMA" with lithium-ion rechargeable battery

A deep sea cruising AUV "URASHIMA" has been developed by JAMSTEC since July 1998. Some performance tests for URASHIMA on the land, in the tank and dock have been already finished in March 2000. Sea trials for URASHIMA have been done since June 2000 at Sagami-bay and Suruga-bay. URASHIMA has 2 types of power source. One is a lithium-ion (Li-ion) rechargeable battery and another is a fuel cell. URASHIMA will be able to cruise for about 100 km with Li-ion rechargeable battery and it will cruise for about 300 km with a fuel cell. The test is divided 2 stages by the power sources. The first stage will be planned for a few years cruising with Li-ion rechargeable battery. The goal of the first stage is the depth of 3,500 m, which is the maximum operation depth of URASHIMA, and the range of about 100 km. The second stage will be planned cruising with fuel cell after the first stage. The goal of the second stage is the depth of 3,500 m and the range of 300 km, which is the maximum operation range of URASHIMA. URASHIMA has 3 operation modes, which are UROV mode, acoustic control mode and autonomous mode. UROV mode is to monitor the state of URASHIMA with fiber optics. Acoustic control mode is to control URASHIMA with acoustic communication. Autonomous mode is to cruise on pre-set schedule. The instruments for science researches are an automatic multi-water-sampling system, a CTDO meter, a side-scan sonar, a low light level snap shot digital camera and TV camera