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Class Gift 1977, the first experiments took place!
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In 2017, the alumni of Engineer SUPAERO 1977 class had managed to collect 11,650 euros, a sum used by DAEP in order to rent a device called LIDAR. A wind profiler that increases the intelligence and endurance of drones.
The first LIDAR experiments took place last spring.
11,650 EUROS collected in 2017
The alumni of the engineering class of 1977 had gathered in 2017 around their first class gift to participate in a notable project whose sequel in fine turns out to be “the Mermoz challenge”. The money raised was used by DAEP (Department of Aerodynamics, Energetics and Propulsion) to increase the intelligence and endurance of drones.
From April to June, Jean-Marc Moschetta and his team were able to carry out the experiments using a portable Doppler LIDAR (LIght Detection And Ranging), a technology that provides an almost instantaneous wind profile over the flight test area. The LIDAR was able to be rented thanks to donations from the class of 1977 which had begun in 2017.
HOW DID THE DONATIONS FROM THE 1977 PROMOTION MAKE YOUR CAMPAIGN POSSIBLE?
Jean-Marc Moschetta: Initially the donations were to allow us to buy a LIDAR and to equip a vehicle dedicated to outdoor flight tests. It turns out that the purchase price was well above our budget and probably premature given our limited experience in the use of LIDAR. We therefore decided to rent the LIDAR for a period of 2 months. In parallel, we were able to buy a mini weather station, an ultrasonic anemometer and a quadrirotor to embark this anemometer. This original device allowed us to measure the wind speed at different heights and to correlate our measurements made with the LIDAR. All this equipment allowed us to carry out a campaign that lasted a little more than two months and that we have just finished.
HOW DOES LIDAR WORK AND WHAT DOES IT ALLOW?
JMM LIDAR works with a laser Doppler system that sends laser pulses upwards and then back to the LIDAR after reflection on the “aerosols” in the atmosphere, those small particles invisible to the naked eye that float in the air. The LIDAR Doppler thus works like a wind profiler, i.e. it is possible to have an almost instantaneous estimate of the wind speed components, over distances ranging from 40 to 200 m from the ground surface. We carried out the campaign in a specific location in order to respect the minimum distance from the ground and went to the south of Castelnaudary, a place known in aeromodelling for “gradient flight” type flights (study of the extraction strategies of birds in order to transpose them on drones).
The added value of LIDAR lies in the fact that until now, measurements were only made using sensors embedded in the drone. The LIDAR, as well as the anemometer mounted on the quadrirotor, allow us to have an “absolute” estimate of the wind conditions crossed by the drone during its flight. The purchase of the portable mini-weather station provided us with ground information that allowed us to re-calibrate the various tests more quickly and with greater precision.
Thanks to these studies we have understood the mechanisms of energy extraction contained in the wind and we can transpose it on “intelligent” piloting laws to increase the intelligence and the endurance of our UAVs (on the Mermoz UAV for example). So we answer the question: how to improve the range of the drone by taking inspiration from the flight of South Sea birds like albatrosses?
WHAT ARE THE NEXT STEPS?
JMM: In this campaign, carried out in collaboration with ENAC, we tried to correlate our data as much as possible and the series of probes were calibrated in the wind tunnel at ISAE. This collaboration has been successful and has allowed us to collect a large amount of data that will be analyzed in the coming months. These analyses will be a basis for papers that are expected to be published for the AIAA Aviation Forum 2022 conference in Chicago in June 2022, which we will attend.
