All Seagliders and Deepgliders are equipped with at least pressure, temperature and conductivity sensors, thus providing profiles of temperature, salinity, and density (basic CTD data) for each dive & climb cycle. Many are also equipped with dissolved oxygen sensors (either SeaBird Elec. model 43 or Aanderaa Optode) as well as optical backscatter and fluoremeter sensors (WET Labs ECO Puck models). A variety of other sensors have been carried as well (e.g.., PAR, acoustical, etc.) - contact us for more information.
Data from gliders are controlled by the scientists and agencies that own and operate them. Many of those groups make data, or plots of it, public through websites including the University of Washington, Oregon State University, University of Cyprus, and the Integrated Marine Observing System of Australia. Check through those websites to see data coming from various parts of the world and of varying combinations of sensors.
Gliders are buoyancy driven autonomous underwater vehicles (AUVs), relying entirely on being able to change their density relative to the surrounding water for propulsion. This is why they can be so energy efficient relative to propeller-driven AUVs and typically conduct multiple-month long missions (up to 9.5 mo.) A variable-buoyancy system is used to expand or contract a bladder that is external to the main pressure hull, which is surrounded by seawater under the protection of a fiberglass fairing. This change in volume changes the glider's density, thus providing vertical thrust either up or down the water column. The glider's pitch angle, and thus angle of attack of its wings, relative to the water is controlled by a moving mass inside (main battery, ~9 kg). A downward pitch and negative buoyancy makes the glider dive while an upward pitch and positive buoyancy makes it climb. For steering relative to a given compass direction, the glider can bank from side to side by rolling the same moving mass, thus turning to maintain flight to given waypoints provided by the operator. The glider collects data all along this saw-tooth shaped path underwater, at speeds, depths, and directions given by the pilot and variable on any given dive, if desired. An animation of this process is linked to the adjacent image of a glider diving.
General control and direction of gliders as well as data collection, is conducted through the Iridium satellite communications system which is used to exchange files between a pilot basestation computer and the vehicle during each surfacing. While underwater, they are controlled entirely by code on internal microprocessors which use parameters and configuration files put in place by the pilot either pre-launch or during communications sessions between dives.