Unmanned Systems Technology 038 l Skyeton Raybird-3 l Data storage l Sea-Kit X-Class USV l USVs insight l Spectronik PEM fuel cells l Blue White Robotics UVIO l Antennas l AUVSI Xponential Virtual 2021 report

97 AUVSI Xponential Virtual 2021 | Report lines with periodically changing directions. Referred to as ‘Nadir-Forward- Backward’ (NFB) scanning, it means the scan directions from the centre of the scan lines change consecutively from nadir, to forward +10 º , and then backwards -10 º . NFB also provides an almost complete 3D data set, as vertical surfaces are also captured through its scan pattern. Truong added, “This scanner also incorporates Riegl’s established waveform Lidar technology based on time-of-flight laser scanning. This innovation not only provides echo signal digitisation but also multiple target capability detection, online waveform processing and multiple-time- around processing. This allows for the penetration of even the densest foliage and the ability to be used for a multitude of applications.” The VUX-120 is now commercially available. NWUAV, who we featured regarding its NW-44 two-stroke gasoline engine in UST 5 (December 2015/January 2016), spoke to us about its newest UAV power plant: a hydrogen fuel cell. “The original concept of this proton exchange membrane [PEM] fuel cell propulsion system was developed in cooperation with the Naval Research Laboratory [NRL], based on research NRL has done over the past 15 years, including dozens of flights on various UAVs,” explained Jeff Ratcliffe. “NWUAV is refining that concept with an eye towards manufacturability. After we’ve finished preliminary operational tests, we’re planning flight tests later this year and commercial deliveries for the first quarter of 2022.” The company has opted to pivot into hydrogen-electric propulsion as it views fuel cells as providing a critical middle ground between the long-range capabilities of IC-engine powertrains and the short-range efficiency of batteries. It anticipates PEM fuel cells enabling ranges almost as long as those for engines but at a cost close to that of batteries. It also noted that hydrogen can now come from many sources and can be used safely across a wide variety of industries – further motivators for developing electronic control systems as well as all-new forming, welding and sealing methods in order to produce this system. The PEM stack contains 48 cells and is rated for 1.5 kW of continuous power. It is designed to consume 48 g/hour of hydrogen without relying on any moving parts (an advantage the company sees as key to lowering maintenance requirements). It is capable of quick starts, outputting power within a second of activation, and has a power-to-weight ratio of about 360 W/kg. Unmanned Systems Technology | June/July 2021 Riegl’s new Lidar incorporates NFB scanning NWUAV has unveiled a fuel cell rated at 1.5 kW of continuous power