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Developing engineering model Cobra fiber positioners for the Subaru Telescope’s prime focus spectrometer

Fisher, Charles and Morantz, Chaz and Braun, David and Seiffert, Michael and Aghazarian, Hrand and Partos, Eamon and King, Matthew and Hovland, Larry and Schwochert, Mark and Kaluzny, Joel and Capocasale, Christopher and Houck, Andrew and Gross, Johannes and Reiley, Dan and Mao, Peter and Riddle, Reed and Bui, Khanh and Henderson, David and Haran, Todd and Culhane, Rob and Piazza, Daniele and Walkama, Eric (2014) Developing engineering model Cobra fiber positioners for the Subaru Telescope’s prime focus spectrometer. In: Advances in Optical and Mechanical Technologies for Telescopes and Instrumentation. Proceedings of SPIE. No.9151. Society of Photo-optical Instrumentation Engineers (SPIE) , Bellingham, WA, Art. No. 91511Y. ISBN 9780819496195.

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The Cobra fiber positioner is being developed by the California Institute of Technology (CIT) and the Jet Propulsion Laboratory (JPL) for the Prime Focus Spectrograph (PFS) instrument that will be installed at the Subaru Telescope on Mauna Kea, Hawaii. PFS is a fiber fed multi-object spectrometer that uses an array of Cobra fiber positioners to rapidly reconfigure 2394 optical fibers at the prime focus of the Subaru Telescope that are capable of positioning a fiber to within 5μm of a specified target location. A single Cobra fiber positioner measures 7.7mm in diameter and is 115mm tall. The Cobra fiber positioner uses two piezo-electric rotary motors to move a fiber optic anywhere in a 9.5mm diameter patrol area. In preparation for full-scale production of 2550 Cobra positioners an Engineering Model (EM) version was developed, built and tested to validate the design, reduce manufacturing costs, and improve system reliability. The EM leveraged the previously developed prototype versions of the Cobra fiber positioner. The requirements, design, assembly techniques, development testing, design qualification and performance evaluation of EM Cobra fiber positioners are described here. Also discussed is the use of the EM build and test campaign to validate the plans for full-scale production of 2550 Cobra fiber positioners scheduled to begin in late-2014.

Item Type:Book Section
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Riddle, Reed0000-0002-0387-370X
Additional Information:© 2014 Society of Photo-optical Instrumentation Engineers (SPIE). Part of this research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration. Funding support was also provided by the Kavli Institute for the Physics and Mathematics of the Universe (WPI), The University of Tokyo.
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University of TokyoUNSPECIFIED
Subject Keywords:Cobra, fiber positioner, PFS, piezo, HSC, SuMIRe, Subaru
Series Name:Proceedings of SPIE
Issue or Number:9151
Record Number:CaltechAUTHORS:20180717-141654051
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Official Citation:Charles Fisher, Chaz Morantz, David Braun, Michael Seiffert, Hrand Aghazarian, Eamon Partos, Matthew King, Larry E. Hovland, Mark Schwochert, Joel Kaluzny, Christopher Capocasale, Andrew Houck, Johannes Gross, Daniel Reiley, Peter Mao, Reed Riddle, Khanh Bui, David Henderson, Todd Haran, Robert Culhane, Daniele Piazza, Eric Walkama, "Developing engineering model Cobra fiber positioners for the Subaru Telescope’s prime focus spectrometer", Proc. SPIE 9151, Advances in Optical and Mechanical Technologies for Telescopes and Instrumentation, 91511Y (7 August 2014); doi: 10.1117/12.2054700;
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:87932
Deposited By: Tony Diaz
Deposited On:17 Jul 2018 21:32
Last Modified:16 Nov 2021 00:22

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