Bergen Polar Ice GroupGeophysical Institute, University of Bergen |
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SUMO - Small Unmanned Meteorological Observer
The knowledge of the structure of the lower atmosphere, especially with
respect to temperature, humidity and wind, is the key for the understanding of processes in the
Atmospheric Boundary Layer (ABL). Up to now there is a lack of
affordable measurement systems, applicable for ABL phenomena with horizontal
scales between 100 m up to 10 km. During the past years a corresponding
profiling system (KALI) has been developed at the University of Munich, on the basis of
a remotely piloted vehicle (RPV). Enabling measurements of the atmosphere
up to heights of more than 2 km above ground, as well as horizontal soundings
at different levels, KALI has successfully been used during several field
experiments in Nepal, Bolivia and Germany.
Remotely piloted vehicle KALI for the measurement of temperature and humidity profiles in the atmospheric boundary layer. The picture is taken during the campaign JUIPIT'AYA at Salar de Uyuni, Bolivia. The system is based on an electric powered model aircraft that allows measurements up to 2500 m above ground.
View from above onto KALIs fuselage with dismounted wings. It shows the matchbox sized data logger (upper center), and the meteorological onboard sensors for pressure (upper left beside the battery) and temperature and humidity (shielded by the small tubes attached by tape to the outside of the fuselage).
During a 4 year PhD-project at the Geophysical Institute, University of
Bergen, the RPV's
sensor technology will be upgraded and expanded. The focus will be set
on the
development, installation and evaluation of a system for measurements
of wind
speed and wind direction onboard. For this new small unmanned
meteorological observer (SUMO)
the flow measurements made onboard the RPV
have to be combined with information on ground speed (derived by a GPS
system)
and information on the orientation of the plane referring to the North
direction. Feasibility studies in cooperation with the University of
Applied
Sciences (UAS) at Regensburg, Germany, resulted in two promising
approaches,
applicable for flow measurements onboard KALI. A thermistor anemometer
or a
combination of miniaturized wind wheel and vane are supposed to satisfy
the
special requirements on size and weight given by the RPV. This part of
the work
will be done in close cooperation with the University of Applied
Sciences, Regensburg, Germany, including laboratory wind tunnel
tests. In addition we are working on the replacement of the recent
8-bit data logging by a higher precision system on the basis of free
programmable micro-controllers.
First outdoor test of the miniaturized anemometer (maybe the worlds smallest) intended for flow determination onboard SUMO. It is intended to be fixed on one of the airplanes wing tips. The anemometer is a combination of a slightly modified commercial flow sensor (Schiltknecht) and a self constructed angle decoder.
Another focus of the project is set to improve the RPV's
suitability for the intended operation in polar environments.
The actual version of KALI has already been designed for flights in
harsh
environmental conditions. It has successfully been used in the presence
of
strong and turbulent winds up to 30 m/s and low temperatures in
mountainous regions of the
Nepalese Himalayas and the Bolivian Andes with starting altitudes up to
5000 m
a.s.l. Nevertheless adaptations will be necessary for secure operation
in the
extreme atmospheric conditions due to polar climates. The functionality
has to
be assured down to temperatures of -40°C. Additionally, if started
at costal
sites, from research vessels or at oil platforms, at least temporary
floatage
has to be assured to enable emergency recovery of SUMO from the sea.
Stephan Lämmlein, Professor, University of Applied Sciences, Regensburg, Germany
Tor de Lange, Technician, University of Bergen, Norway
Stefan Kneifel, Student assistant, University of Bergen, Norway
Stephanie Mayer, PhD student, University of Bergen, Norway
Wolfgang Schäper, Electronic Engineer, Germany
Jan Schween, PostDoc, University of München, Germany
Meinhard Seefeldner, Engineer, University of München, Germany
Remotely piloted vehicle KALI for the measurement of temperature and humidity profiles in the atmospheric boundary layer. The picture is taken during the campaign JUIPIT'AYA at Salar de Uyuni, Bolivia. The system is based on an electric powered model aircraft that allows measurements up to 2500 m above ground.
View from above onto KALIs fuselage with dismounted wings. It shows the matchbox sized data logger (upper center), and the meteorological onboard sensors for pressure (upper left beside the battery) and temperature and humidity (shielded by the small tubes attached by tape to the outside of the fuselage).
First outdoor test of the miniaturized anemometer (maybe the worlds smallest) intended for flow determination onboard SUMO. It is intended to be fixed on one of the airplanes wing tips. The anemometer is a combination of a slightly modified commercial flow sensor (Schiltknecht) and a self constructed angle decoder.
Project members:
Dr. Joachim Reuder, Project leader, University of Bergen, NorwayStephan Lämmlein, Professor, University of Applied Sciences, Regensburg, Germany
Tor de Lange, Technician, University of Bergen, Norway
Stefan Kneifel, Student assistant, University of Bergen, Norway
Stephanie Mayer, PhD student, University of Bergen, Norway
Wolfgang Schäper, Electronic Engineer, Germany
Jan Schween, PostDoc, University of München, Germany
Meinhard Seefeldner, Engineer, University of München, Germany