Autonomous under-ice surveying using the MUNIN AUV and single-transponder navigation

This paper reports what to our best knowledge is the first commercially delivered under-ice survey carried out by an autonomous underwater vehicle (AUV). The campaign was completed as a collaboration between Kongsberg Maritime (KM) and Ballard Marine Construction in January 2017. The surveys took place beneath a frozen lake in North America using a rental KM MUNIN AUV, with launch and recovery through a single hole on the ice not much larger than the vehicle itself. Localization was based on inertial navigation and acoustic positioning using single-transponders pole mounted through the ice. No dedicated homing devices were used during recovery. Unlike many previous reports on under-ice AUV missions, the mobilization and operations were low-logistics and truly commercial-off-the-shelf (COTS), that is, without any under-ice-adaptations being made to the AUV or supporting systems. Also, while reduced navigation performance traditionally has been non-consequential to any final data product, the data was in this case required to comply with the S-44 Special Order specification by the International Hydrographic Organization (IHO). This paper reports the operational experience, challenges, and lessons learned when doing commercial AUV operations under ice. Details are also given on the performance and setup of the single-transponder navigation.