Chapter 10 - Underwater vehicles

Abstract

This chapter describes the different types of underwater systems, the basic theory behind vehicle design/communication/propulsion/integration, and explains the means by which a typical ROV gets everyday underwater tasks performed. Underwater vehicles, in the broadest sense, cover manned and unmanned vehicles, with the unmanned vehicles being divided into autonomous underwater vehicles (AUVs) which are nontethered, and remotely operated vehicles (ROVs) which are tethered. The manned versions include submarines and passenger carrying submersibles. The roles of the unmanned vehicles include the use of AUVs by oceanographers to map the features of the ocean and operators such as the oil and gas industry to map the seabed. ROVs are used for many purposes including underwater observation, exploration of the seabed, underwater construction and maintenance of subsea projects and underwater inspection and cleaning of ships' hulls. Simplistically, an ROV is a camera mounted in a waterproof enclosure, with thrusters for maneuvering, attached to a cable to the surface over which a video signal is transmitted. Practically all of today's vehicles use common consumer industry standards for commercial off-the-shelf (COTS) components. The basic issues involved with underwater vehicle power and control can be divided into the following categories: power source for the vehicle, degree of autonomy (operator controlled or program controlled), and communications linkage to the vehicle.