USE Network launch I UAV Works VALAQ l Cable harnesses l USVs insight l Xponential 2020 update l MARIN AUV l Suter Industries TOA 288 l Vitirover l AI systems l Vtrus ABI

23 “The LARS is a similar kind of solution – something made from many brains thinking together, based on the ideas our research engineers had had for some time.” The LARS Conventional launch and recovery of UUVs generally involves lowering vehicles from (or hoisting them onto) a ship’s deck, preferably without imparting any mechanical stresses or shocks to the hull, electronics, control surfaces and so on. Doing so safely is key to smooth and cost-effective battery swaps and data offloads between survey rounds, but it is easier said than done, given the mechanics of ship-based cranes, the weight of most AUVs and the added motion of the sea. Even using slipways with cushioned roller wheels can be dangerous owing to the sudden entry of UUVs into potentially rough waves or a ship’s propeller wash. To circumvent these problems, the LARS solution is designed around a tube-shaped cage or ‘cradle’, which houses the Hugin. This is lowered into the water to a predetermined depth, below the waves and propeller wash, with heave compensation built into an integrated crane to stop any motion from the ship or waves from reaching the cradle below. At time of writing, the LARS was still in development, as a collaboration between Gjelstad’s team and the former Rolls- Royce deck machinery motion-control team (which was acquired by Kongsberg Maritime in 2019). “The Hugin’s nose will be locked into the cradle by a hook or similar mechanism,” Gjelstad explains. “Once in the water and at launching depth – maybe 30-40 m below the surface – the locking system will disengage and the Hugin will put its thrusters into reverse to exit the cradle to start its mission.” It will return after completing its mission by homing in on a Kongsberg iPAP acoustic positioning system installed in the LARS. Once it’s close enough, the Hugin will orientate itself before the entryway of the cradle, move into it, and be locked in place before the entire assembly is lifted out of the water. “The cage will be built from a combination of metals and plastics, to balance between excess weight and the need to keep the AUV fully protected as it enters and exits the ocean,” Gjelstad adds. “Also, the mouth will have a funnel shape to ease the Hugin’s re-entry.” The cradle’s enclosure will serve to protect the Hugin against damage from the splash zone or host vessel. That will enable higher productivity for marine surveyors, as AUV missions can be carried out (or continued) when sea states are higher than that typically considered safe for such vehicles. Lowering and recovering the cradle will be performed from an automated hangar or 40 ft container (as the Hugin is 20 ft in length and the cradle must wrap fully around it without damaging the container walls or mechanics), which will also integrate either a crane, winch or similar mechanism for actuating the cables off the parent vessel’s midship rather than its stern. Ideally that will free up space in what is one of the more cramped ship areas. “There are other benefits too,” Gjelstad says. “You reduce the risk to the crew that AUV recovery poses, and you also keep the launch and recovery cradle away from the propeller wash. And since the LARS will be automated, there will be little chance of damaging the AUV or cradle through human error. “As this announcement is still quite new, we’re waiting until we have a launch customer before getting into prototyping. What we’re working on for now though is testing and improving the Hugin’s ability to navigate into a space the approximate size and shape that the cradle will be, using its INS and an iPAP on the docking target.” Once a customer contract is signed, Gjelstad anticipates that it will take 12 to 18 months to design, build and test a LARS prototype. Unmanned Systems Technology | June/July 2020 Bjorn Gjelstad, 61, followed his family into maritime engineering. His grandfather had worked as an engineer in a Norwegian shipyard and was also an entrepreneur; his father and uncle had been mechanical and electrical engineers for the maritime industry. He studied engineering cybernetics at the Norwegian University of Science and Technology, in 1978, and wrote an MSc thesis on Strapdown Inertial Navigation in Dynamic Positioning. For the following 22 years he managed and led various projects at Kongsberg Maritime on advanced technologies for dynamic positioning, accumulating broad experience across navigation and automation systems in marine vehicles. After that, he applied his experience to the development of the Hugin AUV, working on the platform’s thrust control and satellite links before being made the company’s head of r&d for maritime robotics in 2008, a position he still holds. As well as this official role, he also works as one of Kongsberg Maritime’s intellectual property rights officers, to ensure both the protection and simultaneous transparency of new UUV and USV technologies developed by his team. Bjorn Gjelstad