Share Email Print
cover

Proceedings Paper

ALMA nutator design and preliminary performances
Author(s): Pierre Martin-Cocher; John Ford; Patrick M. Koch; Chih-Wen Ni; Wei-Long Chen; Ming-Tang Chen; Philippe Raffin; Ching-Long Ong; Paul T. P. Ho; Arthur H. Symmes
Format Member Price Non-Member Price
PDF $14.40 $18.00

Paper Abstract

We report the past two years of collaboration between the different actors on the ALMA nutator. Building on previous developments, the nutator has seen changes in much of the design. A high-modulus carbon fiber structure has been added on the back of the mirror in order to transfer the voice coils forces with less deformation, thus reducing delay problems due to flexing. The controller is now an off-the-shelf National Instrument NI-cRIO, and the amplifier a class D servo drive from Advanced Motion Controls, with high peak power able to drive the coils at 300 Volts DC. The stow mechanism has been totally redesigned to improve on the repeatability and precision of the stow position, which is also the reference for the 26 bits Heidenhain encoders. This also improves on the accuracy of the stow position with wind loading. Finally, the software, written largely with National Instrument's LabView, has been developed. We will discuss these changes and the preliminary performance achieved to date.

Paper Details

Date Published: 5 October 2012
PDF: 12 pages
Proc. SPIE 8452, Millimeter, Submillimeter, and Far-Infrared Detectors and Instrumentation for Astronomy VI, 845221 (5 October 2012); doi: 10.1117/12.925809
Show Author Affiliations
Pierre Martin-Cocher, Institute of Astronomy and Astrophysics (Taiwan)
John Ford, National Radio Astronomy Observatory (United States)
Patrick M. Koch, Institute of Astronomy and Astrophysics (Taiwan)
Chih-Wen Ni, Realscene Technology Corp. (Taiwan)
Wei-Long Chen, Chaoyang Univ. of Technology (Taiwan)
Ming-Tang Chen, Institute of Astronomy and Astrophysics (Taiwan)
Philippe Raffin, Institute of Astronomy and Astrophysics (Taiwan)
Ching-Long Ong, COTECH, Inc. (Taiwan)
Paul T. P. Ho, Institute of Astronomy and Astrophysics (Taiwan)
Arthur H. Symmes, National Radio Astronomy Observatory (United States)


Published in SPIE Proceedings Vol. 8452:
Millimeter, Submillimeter, and Far-Infrared Detectors and Instrumentation for Astronomy VI
Wayne S. Holland, Editor(s)

© SPIE. Terms of Use
Back to Top