Development of an Unmanned Deep Submergence Vehicle with Optical Communication Links

Abstract

Recently unmanned submergence vehicle ststems have been playing an important role in ocean exploration and the objects of them have been extended to a deep sea more and more. Vehicles in these systems are operated by the remote control on surface support ships and in most cases an umbilical cable is used for signal transmitting and electric power supply. This cable must be long enough to reach the deep sea. This brings about various problems, and particulary two of them are serious ; One is the increase in the signal transmitting loss which results in getting information of less quality from the deep sea and the other is the increase in restriction on vehicle's motion. To solve these problems, we have developed deep unmanned submergence vehicle system of the launcher type with optical communication links. We have developed the primary umbillical cable and the secondary tether cable as an electro-optical complexed cable for deep sea use, and assembled a prototype system consisting of a launcher, vehicle and surface control units. Furthermore, we have carried out the offshore tests by the total system to confirm the utility of it under actual conditions in the sea and have confirmed the system's performance satisfactory.