Drones Being Tested In “Antenna Testing Chambers” To Prepare Them For Space Bound Missions
© ESA-Anneke Le Floc’h
In 1986, Joseph Barnard established Barnard Microsystems Ltd (BML) as a London based technology consulting firm. In the early 2000’s, BML moved towards the development of unmanned aerial systems (UAS), a field of technology that was slowly growing with great promise. By 2008, BML had the opportunity to compete as a finalist in Britain’s UK MOD Grand Challenge to develop unmanned robotic systems for the British military. Today, BML is recognized as one of the UK’s most prestigious UAS firms holding contracts with The UK Ministry of Defense, Innovative UK, and The European Space Agency (ESA).
BML develops large drones for commercial and military use. All of the designs they create are open-sourced to encourage furthering the UAS market, though any military contracts are classified. BML has been helping to shape the way drones are used in commercial industries such as surveying, mapping, and inspection of pipelines, border patrols, and mineral prospecting. Many of the scenarios in which a BML drone would be used are in areas with limited internet connectivity. To solve this issue, BML uses an array of antennas designed by Immarsat that will ensure drones can remain in contact with the operator even in WIFI denied spaces.
In 2017, BML partnered with the ESA to see just how effective the antenna system could be. The ESA has built several antenna testing chambers to support its goals of accessing the farthest reaches of space. These facilities are the Compact Antenna Test Range (CATR), the Hybrid European RF and Antenna Test Zone (HERTZ), and the Microwave and (Sub) mm-wave Material RF Characterization Laboratories. To test BML’s antenna equipped drone, HERTZ was the best option as it can accommodate larger structures. HERTZ is a 4,306 square foot cleanroom that blocks out all radio interference. The walls, ceiling, and floor are made from thick steel plates. Nearly every surface of the chamber is covered in 18 inch pyramid shaped foam spikes that prevent any external electromagnetic interference.
Because there is no way for external radio feeds to enter HERTZ, the purity and accuracy of antenna systems can be tested. The cleanroom means that flight system hardware can also be safely tested within HERTZ. The ESA relies on antennas for many of its projects, most of which are for space exploration. As explained on their website, being able to test in facilities like HERTZ reduces “the risks inherent in adopting state-of-the-art instruments within ESA programmes and allow future missions to be selected with confidence.” One of these future projects will be testing for water sources during the 2022 Jupiter Icy Moons Explorer mission.
The project ESA underwent with BML was called the Electronically Steered Antenna Array in the Wing of a Remotely Piloted Aircraft. The drone used for the test was BML’s twin engine InView Electronic Support Measures UAV. The drone weighs around 55lbs and has a wingspan of just over 13ft. It has a maximum speed of 76mph and a maximum range of a little under 800 miles. The drone can carry a wide range of sensors to perform multiple missions. The InView Electronic Support Measures UAV is specifically suited to work in areas with limited internet activity which is why testing the Immarsat antenna communication system was critical.
The test revealed that the antennas could receive and transmit a radio signal in an internet denied environment. This means that the drone can be safely and legally monitored in any situation. The test in the HERTZ chamber went beyond proving the safety of the antenna for unmanned earth bound aerial vehicles. The same antenna system will be used for the ESA’s future mission to Jupiter.
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