Development of long-term observation system using cable-restricted underwater vehicle

In order to obtain long-term data of marine resources, we proposed an observation system that can navigate the same trajectory repeatedly without highly expensive sensors such as DVL and INS. Our system consists of a station equipped with a reel and a vehicle for observing the sea floor. The vehicle is tethered to the station by a power and communication cable, and the cable winds or unwinds by the vehicle cruising around a reel. In this paper, we describe long-term observation system using a cable-restricted underwater vehicle and its sea trial performed at 3 m depth.