Sea trials of AUV "R-One Robot" equipped with a closed cycle diesel engine system

This paper presents the outline of an autonomous underwater vehicle (AUV) called "R-One Robot", which is equipped with an air-independent power (AIP) system of a Closed Cycle Diesel Engine (CCDE) for one-day survey, and the results of its sea trials. In August 1996, sea trials of the robot were successfully conducted in the Pacific Ocean about 30 km off Tanabe City, Wakayama Prefecture. In one sea trial, the robot dived for 20 km in 4 hours, passing through 6 waypoints in turn at different depth. The maximum diving depth was 150 m. Through the sea trials, it is confirmed that the CCDE is a suitable and reliable AIP system for long-range AUVs and the R-One Robot can repeatedly cruise for 120 km only by putting fuel oil and liquified oxygen, and changing the carbon dioxide absorbent. The results indicate that the R-One Robot will be not only used for the survey of the seabed but also used as a stable platform for the various and continuous measurement of the properties of middle layer sea water.