1. SMALL WHISKBROOM IMAGER FOR ATMOSPHERIC COMPOSITION MONITORING (SWING) FROM AN UNMANNED AERIAL VEHICLE (UAV): RESULTS FROM THE 2014 AROMAT CAMPAIGN
Alexis Merlaud1, Frederik Tack1, Daniel Constantin2, Caroline Fayt1, Jeroen Maes1, Florin
Mingireanu3, Ionut Mocanu4, Andreas Meier5, Andreas Richter5, Lucian Georgescu2, and Michel Van Roozendael1
DOAS Workshop 2015
(1) BIRA-IASB (2) Uni. Galati
(3) Romanian Space Agency (4) Reev River Aerospace
(5) Uni. Bremen

2. Objective and geometry of SWING-UAV
Original objective: mapping NO2 at a fine spatial resolution (200 x 200 m2) to cover the spatial extent of a satellite pixel in < 1h from a Unmanned Aerial Vehicle (UAV)
H = 3 km, Angular Field of View = 120°, instantaneous FOV = 2.5° (IFOV = 130 m)
a mirror scans across the satellite’s path (ground track), reflecting light into a single detector which collects data one pixel at a time
Swath = 10 km, 600 km2/h at 60 km/h
(OMI pixel = 13x24 = 312 km2 )
Whiskbroom set-up
SWING-UAV during AROMAT DOAS Workshop 2015

3. Context: the AROMAT campaign
AROMAT (Airborne ROmanian Measurements of Aerosols and Trace gases) campaign
Two first weeks of September 2014
Objective: test recently developed instruments for satellite validation
SWING flights were performed in Turceni, SW of Romania
THE FLIGHTS SHONW HERE WERE PERFORMED IN THE FRAMEWORK OF THE AROMAT CAMPAIGN? WHICH INVOLVED 8 RESEARCH INSTITUTES IN ROMANIA INSEPT; Andreas presented the
SWING-UAV during AROMAT DOAS Workshop 2015

4. Geophysical target: the Turceni power plant
SWING-UAV during AROMAT DOAS Workshop 2015

5. The SWING payload - Avantes AVASpec-2048 spectrometer
I now come bacl to the SWING INSTRUMENT based on a an avantes spectrometer, a pc 104 and a scanner
- Avantes AVASpec-2048 spectrometer
nm, 1.2 nm FWHM
- IFOV = 2.6°, Angular FOV = 110°
- 920 g
- 27 x 12 x 12 cm3
- Power consumption: 6 W at 5 V
SWING-UAV during AROMAT DOAS Workshop 2015

6. The Uni. Galati custom-built UAV
- Electrically propelled
- Open cell foam comp.
- Wingspan: 2.5 m
- Speed: 100 km/h
- Ceiling: 3 km
- Autonomy: 1h
- Autopilot
SWING
Video camera
Attitude sensors, GPS, autopilot, etc.
Flying wing built by Reev River Aerospace (RRA) in collaboration with University of Galati
SWING-UAV during AROMAT DOAS Workshop 2015

7. SWING-UAV: take-off
SWING-UAV during AROMAT DOAS Workshop 2015

8. SWING-UAV: flying
SWING-UAV during AROMAT DOAS Workshop 2015

9. SWING-UAV: landing
SWING-UAV during AROMAT DOAS Workshop 2015

10. AROMAT Flight of Sept 11, 2014 Around 9 UT (11 LT) Lasted 40 min
In visual range
Loops of 600 m downwind of the factory
SWING-UAV during AROMAT DOAS Workshop 2015

11. SWING-UAV: DOAS Fits NO2 window: 425-490 nm +O4, H2O, O3, Ring
H20 window: nm
+ring, O3
SWING-UAV during AROMAT DOAS Workshop 2015

12. Time series of NO2 and H2O(v) DSCDs during the flight
SWING-UAV during AROMAT DOAS Workshop 2015

13. Coincidences during the SWING-UAV flight
AirMap, flying at 3 km
Car-based zenith DOAS
Schönhardt et al., 2014
Constantin et al., 2013
SWING-UAV during AROMAT DOAS Workshop 2015

14. Comparisons SWING with coincident Mobile-DOAS and AirMAP
SWING+Mobile
AirMap+Mobile
2km
Wind was blowing from south east, nice correlation on the
SWING-UAV during AROMAT DOAS Workshop 2015

15. Comparisons SWING with coincident Mobile-DOAS and AirMAP
AMF (AirMap) = 1.9
AMF(MobileDOAS)=1.3
AMF(SWING) = 2.7
(with DISORT)
-> Calculated AMFs do not seem to explain all the difference between the three instruments
SWING-UAV during AROMAT DOAS Workshop 2015

16. Conclusions and perspectives
-AROMAT-2014 yielded the best flights performed so far with SWING-UAV with clear signal and spatial gradients-> 4 successful flights on 10 and 11 Sept
-Flight during morning of 11 Sept (AirMap and Mobile-DOAS overpasses) particularly good
-Qualitative agreement but seems difficult to explain difference in SCDs with simple AMF
-More flights planned above the Black Sea, with a UV spectrometer for NO2 and SO2 measurements from ships, in autopilot and at a higher altitude
- Beside technical difficulties, flight approvals to cover large area are still an issue for satellite validation
-Open question: what is the spatial resolution we can achieve from an aircraft?
SWING-UAV during AROMAT DOAS Workshop 2015

18. SWING-UAV during AROMAT DOAS Workshop 2015 Merlaud et al.

19. The SWING payload Top of flight 400 m Collimating lens servomotor
Arduino (interface servomotor, BMP and pc)
BMP 180 (p, T) sensor
Zenith mirror
SWING-UAV during AROMAT DOAS Workshop 2015

20. Outline Objectives, instrument geometry, context
Instrument and platform
AROMAT flight of 11 Sept 2014
Conclusions and perspectives
SWING-UAV during AROMAT DOAS Workshop 2015