The purpose of this research is to develop an "underwater glider with independently controllable main wings" for the use of oceanographic survey and worldwide-scale monitoring of marine environment by using a number of swarm-intelligent underwater gliders. The experimental underwater glider ‘ALEX’ was designed for much of a high performance of motion. The CFD technique was applied to estimating hydrodynamic forces in different conditions of glider's attitude and environmental flow. Various kinds of experiments lead to the conclusion that the "underwater glider with independently controllable main wings" had an admirable motion capability as compared with conventional "underwater gliders with fixed main wings".
It has become possible to conduct ocean exploration or underwater operation using a variety of underwater robots in recent years. They are roughly categorised into "Human Occupied Vehicles (HOV)" and "unmanned underwater robots" (Ura and Takagawa, 1994). Manned research submersible "SHINKAI 6500" of Japan Agency for Marine- Earth Science and Technology (JAMSTEC) is very famous as the deepest manned underwater vehicle in the world. Deep-sea cruising Autonomous Underwater Vehicle (AUV) "URASHIMA" and 10,000 m class deep-sea Remotely Operated Vehicle (ROV) "KAIKO" of JAMSTEC are masterworks of Japanese underwater robotics. However, the vehicle of ‘KAIKO’ was regrettably lost in 2003, and 7,000m class ROV ‘KAIKO 7000 II’ is now in operation. Several different types of AUV and ROV also have been developed for small-scale investigation or personal use. Underwater glider is one of manageable underwater vehicles for its simple mechanics; accordingly manufacture and operation cost will be relatively low. Underwater glider has no propulsive machinery, so that this silent and safe underwater vehicle can be maintained with ease and is easy on ocean environment and many forms of life in the sea.
