Underwater glider

[1] The typical up-and-down, sawtooth-like profile followed by a glider can provide data on temporal and spatial scales unattainable by powered AUVs and much more costly to sample using traditional shipboard techniques.

[3] The sawtooth glide pattern, stealth properties and the idea of a buoyancy engine powered by the swimmer-passenger was described by Ewan Fallon in his Hydroglider patent submitted in 1960.

[4] In 1992, the University of Tokyo conducted tests on ALBAC, a drop weight glider with no buoyancy control and only one glide cycle.

[citation needed] The DARPA SBIR program received a proposal for a temperature gradient glider in 1988.

The University of Washington Seaglider, Scripps Institution of Oceanography Spray, and Teledyne Webb Research Slocum vehicles have performed feats such as completing a transatlantic journey[7] and conducting sustained, multi-vehicle collaborative monitoring of oceanographic variables.

They were initially designed to quietly track diesel electric submarines in littoral waters, remaining on station for up to six months.

By 2012, a newer model, known as the ZRay, was designed to track and identify marine mammals for extended periods of time.

[13][14] Since they are propelled by a buoyancy engine, gliders have moving parts that are only active occasionally, so there are minimal mechanical vibrations and noise, making them excellent vehicles for sensitive instrumentation including microstructure probes[15] and acoustic sensors.