Unmanned Systems Technology 022 | XOcean XO-450 l Radar systems l Space vehicles insight l Small Robot l BMPower FCPS l Prismatic HALE UAV l InterDrone 2018 show report l UpVision l Navigation systems

75 than lithium batteries can provide. The module provides 800 W of continuous power and 1.4 kW of peak power. The stack’s output power is run through a DC-DC converter, giving the user repeatable, regulated voltage output between 19.6 and 25.2 V (environmental conditions and time between uses can cause output voltage to vary otherwise). “A fan on the rear of the housing draws air through the open-cathode fuel cell,” said Andy Kelly. “Some of the air is used by the electrochemical reaction in the cells, as it needs oxygen to convert hydrogen into electrical power and water, but most of it is used to cool the fuel cell because a significant output of the electrochemical reaction is heat. “By cooling with air, we don’t need radiators or pumps, so our unit can be much lighter and more energy-dense.” The 880 g system is rated to a maximum altitude of 3 km, and integrates a small hybrid battery, an XT-60 power output connector, a UART comms port and a lightweight regulator. ARA Robotics was exhibiting its Skymate flight controller (and constituent systems) for commercial UAS manufacturers targeting 2D and 3D aerial inspection and mapping. “We’ve chosen the data storage unit inside the Skymate to work with the streams and quantities of data to be collected by Lidar and EO survey cameras,” said Guillaume Charland- Arcand. “The standard flight controller kit also integrates our GPS antenna, a power management unit that covers batteries from 2S to 6S in terms of voltage, and a 900 MHz data link with a 1 km range.” The company also supplies a range of accessories, including its 150 g Power Monitor Pro power management unit, which covers battery packs up to 12S, and an RTK kit (including rover and base station) to bring georeferencing accuracy from 1-2 m to 1 cm. It also offers a dual antenna mode, which enhances orientation precision and protects against electromagnetic interference, and a 50 g I/O expander that can allow up to four extra motors to be connected. CR Flight debuted its counter- rotating brushless DC motor, which uses a single motor rather than two to spin its two propellers. As John Emigh told us, “It operates using a three-phase slip ring so that we have a prop on both the armature and the stator – allowing us to spin the stator. So rather than having the stator sit still and aggregate heat in its coils, we effectively turn the stator into an axial compressor. “That, with the housing-mounted propeller, draws air into the motor and pulls it out as well, helping significantly with cooling and allowing the motor to pull 100% more power without overheating.” The motor uses 28 permanent magnets and 24 electromagnets, and consumes up to 36 A at 12.5 lb of thrust at constant duty thanks to the persistent cooling. It can produce up to 17 lb of thrust for a few minutes at a time if needed. It has no output shaft; instead, the InterDrone 2018 | Show report Unmanned Systems Technology | October/November 2018 Intelligent Energy’s 800 W fuel cell is designed as a turnkey solution The Skymate flight controller from ARA Robotics