A garage is about the simplest piece of infrastructure a machine can have. Somewhere to park, a charger on the wall, a shelf for the tools, and a door you roll out of when there’s work to do.<\/p>\n
Nobody writes press releases about garages. Except one of them sits on the floor of the North Sea, and the machine that parks in it picked up the world’s first resident subsea drone contract largely because of it.<\/p>\n
The machine is the Saab Sabertooth, a roughly 12-foot electric underwater vehicle developed by Saab’s teams in Sweden and the UK. In 2022, Norwegian energy giant Equinor awarded UK contractor Modus the first contract anywhere<\/a> for a subsea drone that lives at its work site: docked on the seabed at Johan Sverdrup, western Europe’s largest oil field, charging between jobs instead of riding a ship home.<\/p>\n The living arrangement is literal. The docking station recharges the robot, stores its tool packages, sends new mission instructions down and pushes survey data up to shore by satellite or cable. Saab says the vehicle can sit there 24\/7 for more than six months without maintenance.<\/p>\n Underwater robots come in two flavors. Remotely operated vehicles hang off a cable that feeds them power and commands, with a ship parked overhead paying a crew by the day. Autonomous vehicles swim free on batteries, which is cheaper, right up until you need one to actually turn a valve.<\/p>\n The Sabertooth’s pitch is that you don’t have to pick. Modus chose it for the Equinor job because, per Saab, it’s the only hovering system on the market that runs free-roaming autonomous missions and tethered intervention work from the same hull. Six thrusters give it 360-degree maneuverability, so it can hold position in front of a structure like a hummingbird instead of doing flybys.<\/p>\n The standard vehicle is rated to 1,200 meters (about 3,900 feet), and the double-hull version takes a 3,000-meter option. Jan Siesj\u00f6, the Saab engineer the company credits as the father of the platform, dates the project to 2008, when, as he has told it, people treated the whole idea as science fiction. The yardstick has since flipped, because the question he says the industry asks him now is why underwater robots aren’t as smart as a robot vacuum.<\/p>\n There’s an American party trick on the r\u00e9sum\u00e9 too. In 2015 the vehicle ran a demonstration at NASA’s Neutral Buoyancy Lab, the giant astronaut training pool in Houston, according to SPE’s Journal of Petroleum Technology<\/a>. The milestones stacked up from there: acoustic comms in 2019, an electric manipulator in 2020, and the one this whole story hangs on, fully autonomous docking in 2021.<\/p>\n A seabed docking station sounds like an accessory. It’s closer to the whole business model.<\/p>\n Siesj\u00f6 was blunt about it in that JPT piece: keeping a robot underwater for months is easy, he argued, provided “you have a power supply and communication and you don’t do anything stupid.” The hard part was never the robot. It was that every battery eventually runs out 500 meters from the nearest outlet.<\/p>\n The station Equinor pushed for solves that. It’s an open-standard design developed by Norway’s Blue Logic with Equinor’s backing, a flat structure of roughly 8.5 by 9.4 feet that gets lowered to the bottom by crane<\/a> and was deliberately built so any maker’s drone can land on it. Saab, Saipem, Oceaneering, Eelume and Subsea 7 all sat in the design workshops. Think of a gas station that takes every brand of car.<\/p>\n Inductive pads charge the parked vehicle the way a pad charges your phone. Tooling gets stored on the structure. Data goes up, instructions come down, and the surface ship goes away. Peter Erkers, Saab’s sales director for underwater systems, said in 2023 that resident systems were the next step and that “we are already developing an underwater garage for it.”<\/a> His phrase, not mine.<\/p>\n Then there’s the math. Siesj\u00f6 has put the daily rate for an advanced dive-support ship at more than $200,000. A 2025 Offshore Technology Conference paper cited by JPT prices a docking station at $1 million to $2 million, one time. If the garage saves you two weeks of ship charter, it has roughly paid for itself, and the ship it replaces also burns fuel, feeds a crew and waits out storms.<\/p>\n The residency idea went public in February 2019, when Saab Seaeye showed a Sabertooth docking at a remote station for charging and data transfer, a capability the company billed as a world first. That June, industry reps gathered at Sweden’s Lake V\u00e4ttern to watch it run mock inspection missions from Equinor’s open-standard station and come back for recharging.<\/p>\n In November 2021, Modus closed the loop off northeast England: a Sabertooth left an Equinor and Blue Logic station, flew a pre-planned survey, navigated back and parked itself with no manual intervention. Ten months later came the money. Equinor handed Modus what both companies billed as the world’s first resident subsea drone contract<\/a>, running from 2023 to mid-2024 at Johan Sverdrup, with missions flown over the horizon from Modus’ control room in Darlington, England.<\/p>\n Autonomous surveys and light intervention on a producing oil field, run by an operator sitting in an office in the north of England. The robot stayed down. The commute belonged to nobody.<\/p>\n Neither company has published a sequel to that deal, and the program’s public paper trail goes quiet after the contract term. The concept it proved is a different story.<\/p>\n If the name Sabertooth rings a bell outside the offshore trade press, this is why. In March 2022, the Endurance22 expedition located Ernest Shackleton’s Endurance under the Weddell Sea ice, 106 years after the pack crushed it. The wreck sat at 3,008 meters<\/a>, roughly four miles from where Captain Frank Worsley’s sextant said it went down, and the search vehicles were Saab Sabertooths run from the South African icebreaker S.A. Agulhas II.<\/p>\n National Geographic turned the hunt into a documentary. Saab turned it into a sales pitch, and a fair one: within 15 months, marine survey firm PXGEO ordered more than 20 Sabertooths, the largest single order in the platform’s history, to plant and recover seismic sensors on the seabed. PXGEO had rented one first and tested it for over a year, which is the underwater robotics version of an extended test drive.<\/p>\n The garage concept has spread well past one Swedish robot. Saipem’s Hydrone-R logged 165 straight days resident on Equinor’s Njord field in 2023, then went back for more, reaching 240 cumulative days and over 280 dockings by January 2025, per JPT. The same reporting counts about a dozen more docking stations under consideration off Norway.<\/p>\n The bet has gone renewable, too. At the U.S. Navy’s Wave Energy Test Site off Oahu, Hawaii, a trial program pairs a Sabertooth with C-Power’s SeaRAY wave-energy system, so the drone patrols, docks and recharges on power harvested from the waves<\/a> above it. The Department of Energy, the National Renewable Energy Laboratory and the Navy itself are partners on that one.<\/p>\n And the residents keep multiplying. Norway’s Eelume, the six-meter drone snake that also lives in a seabed dock<\/a>, picked up a Norwegian defense research contract this April. A Canadian hydrogen drone can anchor itself to the bottom and watch a cable for 16 days<\/a> straight.<\/p>\n A Kiwi-British startup sells a tethered seabed drone built for guarding pipelines<\/a>, and Kongsberg’s survey drone recently spent 15 days alone mapping seafloor<\/a> where Europe’s cables keep getting cut. Different machines, same conclusion: the expensive part of underwater work is the boat.<\/p>\n The Sabertooth got to that conclusion before it was fashionable, which is what happens when your engineers start in 2008 and get treated like they’re pitching science fiction. A robot that lives in a garage, charges overnight and keeps its tools on a shelf sounded exotic back then.<\/p>\n It shouldn’t have. You’ve owned a robot vacuum on that exact schedule for years. This one’s garage costs a couple million dollars and sits at the bottom of the North Sea, and every month it works down there is a month nobody rents the $200,000-a-day ship.<\/p>\n","protected":false},"excerpt":{"rendered":" A garage is about the simplest piece of infrastructure a machine can have. Somewhere to park, a charger on the … <\/p>\nIt works on a leash or with no leash at all<\/h2>\n
The garage is the clever part<\/h2>\n
Equinor turned the demos into a contract<\/h2>\n
The same robot found Shackleton’s ship<\/h2>\n
The neighborhood is filling up<\/h2>\n