Development of a solar-powered underwater glider

Several kinds of autonomous underwater vehicles (AUVs) are now in operation for scientific investigation and industrial survey. One of the most important issues of AUV operation is power supply. An alkaline or lithium-ion battery is usually equipped in AUVs, but operational duration is restricted to several hours owing to limitations in space for battery storage. However, underwater gliders driven by a buoyancy engine have a high degree of energy efficiency. The purpose of this research is to study the feasibility of an underwater glider powered by a solar battery so as to realize enhancement of the endurance. The experimental glider, SORA, is equipped with solar panels on the main wings and the upper side of the fuselage, and two thrusters on both sides of the frontal body. Tank tests were conducted to validate the solar-powered underwater gliding system.