The navigation system for an expendable fiber cable ROV “UROV”

The Japan Marine Science and Technology Center (JAMSTEC) have developed a free-swimming expendable fiber cable ROV “UROV” for under sea investigation that was built in co-operation between Fukui Prefectural Fisheries Experimental Station and JAMSTEC in 1992. Sea trials proved that it is able to swim over 1000 meters near the seafloor during two hours operation within the battery limits. Normally, the navigation for UROV is done manually by operators, using its position from navigation computer based on not only an acoustic underwater positioning, but also a GPS receiver and a compass on the board. In the navigation computer an auto-pilot mode has been installed to control UROV automatically along a preset route instead of the joystick, if the Radio Technical Commission for Maritime (RTCM) 104 message from a reference station placed at a known location is available (Differential GPS mode). This paper describes the navigation system for UROV