Undersea gliders

Undersea gliders offer an alternative propulsion paradigm to the propeller-driven autonomous underwater vehicle by using buoyancy change and wings to produce forward motion. By operating at slow speed (<0.5 ms-1 ) and being frugal with the electrical power available to the vehicle’s control and support systems and sensor payload (typically less than 1 W on average), long endurance can be achieved (over six months, or over 3,000 km). With two-way satellite communications from the sea surface, gliders can send their data ashore and receive new mission commands, enabling powerful new concepts in making ocean observations. Glider missions to date have concentrated on gathering data in support of biophysical and physical oceanography, contributing to studies on ecosystem dynamics, red tides, ocean circulation and climate-related research. Operations have taken place in Polar regions through to the tropics, with hazards including sea ice, hurricanes and vessel traffic. Advances in technology are likely to enable next-generation undersea gliders to travel further, dive deeper, carry more advanced payloads such as chemical and biological sensors and perform in more intelligent or cooperative ways.