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

60 Insight | UUVs signatures, say before entering potentially contested waters,” says Jacqueline Nichols, from business development at Cellula. “Some people in the industry wanted to know what their ships ‘sound like’, both magnetically and acoustically, while travelling. They usually have to navigate a new ship to one of two static ranges in Canada to measure that, but after only a couple of months of travel, the ships build up a newmagnetic signature, and their measurements become obsolete.” Like the Solus-XR and LR, the Imotus-S is programmed with Cellula’s centralised, ROS-based computer and network architecture, which Johnson explains is equally capable of controlling a UUV with a slow cruise (like the XLUUVs) or one like the Imotus-S that can use its eight ducted thrusters to remain stationary, so long as it is equipped with an IMU, DVL and other standard navigation systems. “The Imotus-S craft hold their positions in water, working as a swarm, and their host ship moves around either near or above it depending on their relative positions, so that the UUVs can take measurements from different distances and angles,” Nichols explains. As of December 2022, sea trials off the coast of British Columbia of the first prototype of the Imotus-S had concluded successfully, with future iterations being aimed at containerised launch and recovery solutions (as opposed to the current approaches based on ship cranes), as well as further miniaturisation of the UUV to make it portable by one person. Just as the Canadian defence forces are requesting UUV innovations from Cellula to match its growing maritime ambitions across the Pacific and Arctic, so the Royal Australian Navy (RAN) is working with companies such as C2 Robotics to achieve greater capabilities and more ambitious mission goals with the latter’s Speartooth LUUV. This is an 8 m-long, 1 m-beam hybrid- electric vehicle, developed for a range of 2000 km between refuelling and operations down to 2 km below sea level. Its design targets also include modularity and scalability – specifically the ability to manufacture it rapidly in high volumes and at lower costs than has been typical of the UUV industry. These are key factors in the growing success of micro-AUVs such as the ecoSub (see UST 28, October/ November 2019) and the Seaber YUCO ( UST 46, October/November 2022). “The overall outer frame, control surfaces and propulsion system generally don’t change greatly per customer, but power systems, payload space, buoyancy compensation systems and a range of other factors can all be customised by inserting or removing key modular segments to achieve different mission objectives,” explains Tom Loveard, CTO at C2 Robotics. “Even the size of the vessel’s hull can change to a degree by using extended centre payload segments. My experience of building autonomous systems tells me that the minute we lock in a specification to a fixed value, the next customer will want to change it in some critical area, which can be very-time consuming and costly to work around.” So although there is an initial 2 km depth capability requirement that Loveard and his engineering team have worked towards, that figure will not be a requirement in all cases. Some heavier and bulkier components can therefore be replaced if less depth capability is needed for a new user’s mission set. “The Speartooth is thus a vision for designing systems that are far more adaptable to changes in mission sets or improvements in technology,” he continues. “If some great new subsystem element is developed tomorrow, the integration effort is more rapid, and older systems can be easily updated through modular replacement. I think this will be a critical factor for successful asymmetric warfare systems in the future.” The scalability is also intended to bring down the Speartooth’s price point, as traditional defence UUVs owe much of their exorbitant cost to the fact February/March 2023 | Uncrewed Systems Technology The hybrid-electric Speartooth AUV is being developed as a modular and scalable solution for the Royal Australian Navy (Courtesy of C2 Robotics)