Uncrewed Systems Technology 048 | Kodiak Driver | 5G focus | Tiburon USV | Skypersonic Skycopter and Skyrover | CES 2023 | Limbach L 2400 DX and L 550 EFG | NXInnovation NX 100 Enviro | Solar power focus | Protegimus Protection

66 Insight | UUVs integratewith our stack using different computer languages and at different levels, whether theywant just bare bones transmit-receive capability or custom protocols to support content-aware end- to-end connectivity,” he concludes. Oil & gas HAUVs are also gaining in popularity elsewhere in the energy industry. While UUVs have long been launched for (and recovered from) pipeline inspections, there has been growing discussion about the concept of resident UUV operations. That means having one or more UUVs stowed in an undersea hangar at some critical infrastructure where it sits, charging or refuelling, until it needs to carry out its periodic inspection duties, or is remotely activated to check for damage if a sudden fault in the asset is suspected. As a result, the typically high costs of launching and recovering UUVs (which are normally driven up by needing a large vessel with a suitable crane) could be significantly reduced, as could the emissions associated with such vessels. UK-based Modus has received what it claims to be the world’s first contract for resident UUV operations. One of its HAUVs will be deployed from this year to mid-2024 for “underwater intervention drone operations” at Equinor’s Johan Sverdrup field, following successful trials with the Norwegian energy company in November 2021. The Modus HAUV-1 is a double-hulled Sabertooth model from Saab Seaeye (see UST 36, February/March 2021). It achieves propulsion and hovering through seven electric thrusters distributed about its hull, specifically Saab’s SM9 model which draws 9 A during nominal operation to produce 60 kg of thrust at 250 V DC, or 100 kg of force if 500 V DC is supplied. Its battery holds up to 30 kWh, enabling more than 14 hours of endurance and powering four 3200 lumen floodlights as well as a variety of payload sensors. These include cameras fromAxis and Bowtech, and sonars from iXblue/Exail, Edgetech, Norbit and Teledyne. As well as charging underwater, the Sabertooth will probably perform underwater data transfers, enabling near real-time analyses of its survey and inspection findings without having to waste time or battery energy surfacing to establish an RF data link. Summary The systems described here suggest that the growing specialisation of UUVs in their mission sets seems to be bringing with it a greater emphasis on station- keeping rather than speed or efficiency of movement. Be it through buoyancy engines, thrusters or suction anchors, it appears that the more tasks end-users demand of UUVs, the more they want them to stay still. It might sound peculiar, but station- keeping and hovering are key to how UUVs can zero in on points of interest that are vital to underwater asset owners, and carry out tasks beyond just close observation. If autonomous subsea robots can performmining or mechanical intervention tasks, it might only be a matter of time before they are entrusted with underwater construction, repair or scientific sampling tasks that have traditionally been entrusted to human operators. While innovations in deep machine learning and other software- defined AI are enabling more and more edge cases on land to be tackled, many other use cases below water are waiting to be addressed. February/March 2023 | Uncrewed Systems Technology Modus’ Saab Sabertooth HAUV is set for use as a resident system in Equinor’s Johan Sverdrup oil field (Courtesy of Modus)