DEVELOPMENT OF A BOREHOLE DEPLOYABLE REMOTELY OPERATED VEHICLE FOR INVESTIGATION OF SUB-ICE AQUATIC ENVIRONMENTS

Investigation of sub-ice aquatic environments on Earth requires highly specialized methods. While ice offers a convenient, stable deployment platform for remotely operated vehicles (ROVs), traditional tethered vehicles with cuboid form-factors require large diameter holes that necessitate impractical logistics for ice-drilling support. While access beneath the front of an ice shelf edge is possible with traditional ship or boat deployed autonomous underwater vehicles (AUVs) or ROVs, accessing the water column towards the grounding zone of larger ice shelves involves distances beyond the effective range of current AUVs or tethered systems, unless they are deployed through the ice. Many such sub-ice environments are found on and around the continent of Antarctica but only a handful of underwater vehicles have been successfully used in Antarctica to date, which has limited the extent of scientific investigation in these environments. Borehole vehicles have been successfully demonstrated in the past and we describe here a significant improvement on their past depth and sensorial capability. Finite volume structural, thermal, and fluid analysis was used to design a ROV which is a highly reconfigurable, 2 km depth capable, 750W powered, and under 25cm in diameter. The vehicle is suitable for observation and light intervention in the water column or at the seafloor under any ice shelf in Antarctica and many subglacial lakes. In January 2015, this vehicle successfully completed a survey mission through 740m of ice into an ~11m tall water cavity, near the grounding zone of the Ross Ice Shelf. Advisor: Ben Terr