Development of an ROV operated both as towed and self-propulsive vehicle

A remote-operated vehicle (ROV) developed for investigations of the sea bot tom over a wide area can be operated as both a towed and a self-propulsive vehicle. Called DELTA, the shape is similar to that of a delta-wing aircraf t. The vehicle has two propellers and weight shift apparatus as actuators. The paper describes the design of the control system for the vehicle. Non-l inear motion equations of the towing cable and DELTA are discussed, followe d by a description of the LQI control system and robust control based on H- infinity control. Depth control performance was improved by the robust cont roller. Some successful experimental results are shown. (C) 2000 Elsevier S cience Ltd. All rights reserved.