Exocetus Coastal Glider
The Exocetus Development LLC Coastal Glider was developed under funding from the Office of Naval Research during a 6- year period. Eighteen gliders were delivered to the US NAVY during these six years, and the gliders have a combined 4,500 hours of operation. Exocetus [x-o-seat-us] Coastal Gliders were designed to operate in coastal waters where high currents and large water densities occur due mostly to the fresh water entering these coastal waters from rivers. Legacy gliders [the Slocum, the Seaglider, and the Spray], which were developed over the past 15 years and were designed for open-ocean operations, do not have the capability to operate in coastal waters due to design limitations. Unlike legacy gliders, the Exocetus Coastal Glider was designed to easily add more sensors without any, or minimal changes to the glider housing.
The Exocetus Coastal Glider has a buoyancy engine more than 7 times larger [5 liters] than the legacy gliders which allow operations over wide variations of water densities by use of a proprietary adaptive ballasting system. The ballasting system allows the Exocetus Coastal Glider to be deployed without the pre-ballasting requirement of the legacy gliders. This larger buoyancy engine also permits the Exocetus Coastal Glider to easily operate in waters with up to 2 knots of current. The Exocetus Coastal Glider can operate down to depths of 200 meters which is more than adequate for most, if not all, coastal applications.
The Exocetus basic glider model is designed to operate for approximately 14 days with an alkaline battery pack and for 60 days with a lithium pack; however, these operating times can be extended using the glider’s variable speed capability and using fewer excursions to the surface for data telemetry. The glider has four modes of communication: Iridium satellite, Service ARGOS (being implemented), Freewave [UHF] line-of-sight and WiFi. Acoustic modems can be added for communication with underwater devices.
Also, the Exocetus basic glider model has an AML Oceanographic CTD/SVTP sensor and a Tritech acoustic altimeter. Additional sensors integrated in the glider during the past several years include omnidrectional hydrophones by Reson, vector sensor hydrophones by Wilcoxon, WetLabs water quality sensors, and RINKO fast response DO2 sensors. Designs also exist for the SeaBird pumped CTD sensor suite, the Satlantic SUNA nitrate sensor and a LND gamma ray [calibrated for Cesium-137] sensor.
The following types of Coastal Glider systems are now in our fleet of gliders.
• Hypoxia Glider with a CTD, DO2 and water quality sensors
• Wind Assessment Glider with a set of hydrophones
• Radiation Monitoring Glider with a Cesium-137 sensor