The design and 200 day per year operation of the Autonomous Underwater Vehicle Sentry

The Autonomous Underwater Vehicle (AUV) Sentry has been in routine operation since 2009. It is a 6000m depth rated autonomous survey and sampling platform and is a “fly-away” system meaning it transports easily anywhere in the world to utilize vessels of opportunity. Sentry, initially a radical concept and experiment in AUV design, is now the AUV component of the National Deep Submergence Facility (NDSF) operated by Woods Hole Oceanographic Institution and as such spends up to 200 days per year in the field conducting operations for ocean scientists. Accordingly, Sentry must be reliable enough for a customer focused mission, but flexible enough to undertake previously unconceived missions on very short notice and with a high success rate. Field operations on a “Global Class” research vessel can easily exceed $100,000 per day placing a premium on efficiency. Here we describe not only the vehicle Sentry, but also, the systems and infrastructure which supports Sentry and the unique nature of operations within the NDSF.