| Autor: |
Hans-Ulrich Wieland, Adrian M. Glauser, J. Sykes, Jérôme Amiaux, R.-R. Rohloff, Armin Huber, H. Merkle, M. Ebert, Torsten Gross, Stephan M. Birkmann, Th. Henning, F. Müller, Ralph Hofferbert, M. Übele, Georg Luichtel, Rieks Jager, Oliver Krause, Ulrich Grözinger, T. Fischer, Silvia Scheithauer, A. Böhm, P. Parr-Burman, Dietrich Lemke |
| Rok vydání: |
2010 |
| Předmět: |
|
| Zdroj: |
SPIE Proceedings. |
| ISSN: |
0277-786X |
| DOI: |
10.1117/12.856887 |
| Popis: |
The Mid Infrared Instrument (MIRI) aboard JWST is equipped with one filter wheel and two dichroic-grating wheel mechanisms to reconfigure the instrument between observing modes such as broad/narrow-band imaging, coronagraphy and low/medium resolution spectroscopy. Key requirements for the three mechanisms with up to 18 optical elements on the wheel include: (1) reliable operation at T = 7 K, (2) high positional accuracy of 4 arcsec, (3) low power dissipation, (4) high vibration capability, (5) functionality at 7 K < T < 300 K and (6) long lifetime (5-10 years). To meet these requirements a space-proven wheel concept consisting of a central MoS2-lubricated integrated ball bearing, a central torque motor for actuation, a ratchet system with monolithic CuBe flexural pivots for precise and powerless positioning and a magnetoresistive position sensor has been implemented. We report here the final performance and lessons-learnt from the successful acceptance test program of the MIRI wheel mechanism flight models. The mechanisms have been meanwhile integrated into the flight model of the MIRI instrument, ready for launch in 2014 by an Ariane 5 rocket. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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