Award of Purchase of Goniometer (MS-P-0452)

The Scottish Ministers, Marine Directorate invite tenders for the purchase of a goniometer for the surface detection of the Argos satellite tag on its SeaExplorer Autonomous Underwater Vehicle (AUV).The Oceanography Team of the Marine Directorate of the Scottish Government owns an Autonomous Underwater Vehicle (AUV; buoyancy glider) for the acquisition of oceanographic data. The vehicle operates autonomously under the pilotage of a scientific team, using the communications satellite network to transmit navigation and sampling commands and receive scientific and navigational data. The vehicle surfaces at regular intervals to communicate and also in the event of an emergency which requires the jettison of its ballast, and stays on the surface at the scheduled end of its mission. When the vehicle is on the surface, it is quite vulnerable to marine traffic, so it is imperative that it is recovered by a vessel as quickly as possible.The vehicle is fitted with an Argos satellite tag attached to its antenna, so it is possible to locate its position using positional data from the satellite network. However, the accuracy of the positional information from the satellites and its refresh rate are suboptimal for the speedy recovery of the vehicle, while a goniometer (a highly sensitive direction finder) on board a recovery vessel would allow a much more accurate location of the Argos tag, minimising the vehicle’s vulnerable surface time and also optimising the use of expensive vessel time spent on searching for the AUV.