Perhaps you read our post about the scientists using wave gliders to track white sharks off the coast of southern California in the United States (and making the tracking information available in a mobile app). The Economist recently featured an article about the growing popularity of sea gliders – a similar device – and the broad range of applications for which they are suited. Sea gliders are propelled by buoyancy engines: oil is pumped in and out of a bladder, causing the craft to move up and down in the water column by changing its buoyancy. It is possible to translate this vertical motion into horizontal motion by means of wings. The resulting motion is slow but their running costs are virtually nil.
Because they are silent, gliders can be used to approach and track marine animals without scaring them. They have been used to study oil spills, underwater volcanoes, and radiation leaking into the ocean from the Fukushima reactor in Japan. There are (of course… sigh!) military applications for these craft, and sooner or later commercial use is expected to boom too.
Read the full article here.
