PROJECT BACKGROUND
ESA is developing the third generation of weather forecast satellites, METEOSAT THIRD GENERATION (MTG).
Leonardo is in charge of the design, manufacture and testing of the Lightning Imager (LI), an instruments which allows to “see” LIghtings from 36,000 kg above Earth atmosphere.
CUSTOMER REQUEST
To test and calibrate the Lightning Imager (LI) optical instrument, Leonardo needs a high precision positioning system. The system is integrated into a thermo vacuum chamber (TVC), thus is must be compatible with a clean and vacuum environment.
The system positions the instrument with respect to the Optical Ground System Equipment (“OGSE”) located outside of the TVC with a high travel range:
■ COne rotation scan (Rxy ±5.1 deg) over 4 different optical channels■ High cone rotation scan (Rxy ±16 deg) with a COR 1,000 mm away in Z
Furthermore the sytem must be preceise and thermically stable.
THE SOLUTION
To meet the high travel range requirements, specifically over X & Y axis, as well as the distant center of rotation, SYMETRIE has developped and integrzted a 2 axes module. This solution allows to performe high amplitude motions without the constraint of designing a too big hexapod.
This table is integrated to a ZONDA hexapod which meets the need for high precision, payload and travel range:
■ The XY table allows to change the optical channel as well as to make an importante cone with a distant CoR.■ THe ZONDA hexapod allows to position the instrument and then to performe an angular scan.
FUrthermore thermal braids and temperature sensors are integrated in order to guarantee an optimal stability.
PROJECT SPECIFICITIES
■ 10 -6 mbar vacuum
■ Cleanroom compatibility
■ 8 axes
■ Stability and angular precision (Stability < 2 µrad per 15 min and Accuracu <15 µrad / deg)
■ Payload 150 kg
