I enjoyed this youtube interview with Doug Webb, creator of the Slocum Glider. Everytime I see these things, I marvel at the ingenuity. Very cool.
An article in Engineering and Technology Magazine about how they're being deployed:
A fleet of 16 autonomous underwater gliders will be sent off to explore the world’s oceans as part of an ambitious research project by Rutgers University researchers.
Part of the Challenger Glider Mission Project, the underwater drones, each 2.2 metres long, will cruise the oceans at a rather modest speed of 35 km per day gathering data about the current state of the oceans.
Moving forward following a tooth-shaped gliding trajectory, the unmanned submarines will rely solely on energy from buoyancy changes to move forward.
The drones are based on the Webb Slocum glider platform developed by the American company Teledyne. Each of the gliders will be equipped with a GPS receiver together with an altitude sensor, depth sensor and an altimeter for precise navigation. Every time the unmanned submarine surfaces, it will send data to the operators via a telecommunications link provided by Iridium satellites.