|Software for Operational
ARTeMIS software from SVS in the SOFIA
SOFIA, the Stratospheric Observatory For Infrared
Astronomy (SOFIA) is a flying infrared observatory. With this unique
platform, scientists will be able to investigate for example the development
of young stars and planetary systems or to examine the centre of our home
galaxy, the Milky Way.
The ARTeMIS software from Structural Vibration Solutions provides the best
possibility to investigate structures like the SOFIA .
The major part of the infrared light of these celestial objects cannot
penetrate the earth atmosphere due to the absorption of its water vapour.
For this reason the German Aerospace Centre (DLR) and the National
Aeronautics and Space Administration (NASA) started the SOFIA project for
which a Boeing 747-SP was highly modified and equipped with a German
telescope in the rear of the aircraft, weighing 17 tons and having a primary
mirror diameter of 2.7 meter. In an altitude of about 13 kilometres the
atmospheric influence on star observations is negligible, and hence
observers will have an undisturbed view onto the infrared sky. SOFIA will
presumably start with scientific observations in late 2009, which is the
International Year of Astronomy.
The German contribution to the project is the development, construction and
testing of the telescope which is the heart of the observatory. At the
intended aircraft altitude of SOFIA, the telescope will be placed in a
highly unprofitable environment for precise observations. For example the
aero acoustic loads on the telescope due to the open cavity of a size of
about 3 x 3 metres as well as the vibrations of the aircraft itself will
stimulate vibrations of the whole structure. In order to guarantee that the
required pointing stability is met by the observatory, these effects have to
be known and controlled well. Hence engineers from the German SOFIA
Institute (DSI) at the Universitaet Stuttgart , which operates the SOFIA
telescope on behalf of DLR need to derive the exact dynamical parameters of
The ARTeMIS software from Structural Vibration Solutions A/S provides the
best possibility to investigate structures like the SOFIA telescope under
its realistic operation conditions. For that ARTeMIS does not depend on the
use of well defined, artificial signals for the stimulation, but takes
advantage of those provided by the actual disruptions like the wind loads
and aircraft vibration itself. With that approach the DSI engineers can
determine the stimulated telescope vibrations that occur during real
observing conditions and investigate for example their dependence from the
cavity temperature which is about minus 40 degrees Celsius.
SOFIA, the "Stratospheric Observatory for Infrared
Astronomy" is a joint project of the German Space Agency (German Aerospace
Centre, DLR) and the National Aeronautics and Space Administration (NASA).
It is funded on behalf of DLR by federal (Bundesministerium für Wirtschaft),
state (Baden-Württemberg) and University (Stuttgart) means. Scientific
operation for Germany is coordinated by the "Deutsches SOFIA-Institut" (DSI)
of Stuttgart University, in USA by Universities Space Research Association