Underwater observation system using Autonomous Towed Vehicle

On the project of the improvement of Tokyo Bay Waterway, it was needed to take a picture to confirm the effect of the artificial fish reefs constructed by the ruined blocks of the Third Fort of Tokyo Bay. However, in this sea area, the current is fast and the water depth is too deep for diver's work. Therefore, to develop a new system in order to carry out viewing work safely and efficiently was required. An underwater observation system using "autonomous towed vehicle" was proposed and the dynamic characteristic of the system was investigated by the basic motion simulation. Moreover, the hydrodynamic coefficients were determined by the results of the towing tank test. After the stability of the towed vehicle was verified by the examination based on the experimental data, the body of the prototype model was manufactured. This paper discusses the total control system of the vehicle including the collision avoidance method with the obstacle. And the result of the field experiment which uses existing AUV (Autonomous Underwater Vehicle) aiming to confirm the feasibility of the U-GIS (Underwater Geographic Information System) using AUV is also described.