Unmanned Systems Technology 012 | AutoNaut USV | Connectors | Unmanned Ground Vehicles | Cobra Aero A33i | Intel Falcon 8+ UAV | Propellers | CES Show report

24 The law is chasing to catch up with the technical capacity to make autonomous devices. Our USVs are small and slow, embodying little kinetic energy, and so are not a risk to other vessels. “We play a leading part in the development of thinking about regulation in the UK and internationally. A colleague chairs the UK MAS Regulatory Working Group.” Monolithic composite skin All AutoNaut hulls are made from a monolithic (single-skin) composite laminate of glass and aramid-reinforced polyester, the aramid element being two layers of Kevlar 49 fabric that has a useful combination of high tensile strength and good impact resistance. The single-skin composite monocoque does not include a core material because there is enough inherent stiffness in the shape of the shell, which simplifies fabrication and makes repairs easier and more cost-effective. Metal components including the fore and aft foil attachment structures, the lifting hoops, the load-limiting spring at the base of the mast and the bolts that hold the hull sections together and secure other components are made from 316 stainless steel for its exceptional corrosion resistance. For the masts, a woven 3k 2/2 twill weave pre-preg carbon fibre is used. The foils themselves are 3D printed from Nylon 12 using a selective laser sintering process, which enables the company to make intricate, detailed parts with what Poole describes as sub- millimetric precision at a reasonable cost and without expensive tooling. Flexibly mounted masts The mast or masts are bolted to the reinforced deck via the aforementioned stainless steel spring, which allows the mast to flex during extreme events such as a capsize. The masts can support a variety of weather stations and other devices including cameras such as a 360 º stills and video camera, sunlight measuring insolation sensors, radar electronic support measures (RESM) system, radar transponder equipment, navigation lights and more. While AutoNaut will discuss any mast height and configuration that customers want, typically they measure between 1 and 3 m. Poole notes that masts are not a problem, although they do affect the way the boats respond to wind, as well as their stability owing to their weight and that of the sensors attached to them. For example, the company offers a 3 m mast with the 5 m MetOcean AutoNaut because the meteorological buoys they are intended to replace typically place their wind sensors a little higher than 3 m, so that AutoNaut data is broadly comparable. “The real advantage though is that February/March 2017 | Unmanned Systems Technology A 5 m AutoNaut separated into the two hull sections, which fasten together with bolts (Photo: Peter Donaldson) This view shows one of the foil support structures and lifting hoops (Photo: Peter Donaldson)