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 5um 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.
@article{arxiv.1408.2833,
title = {Developing Engineering Model Cobra fiber positioners for the Subaru Telescope Prime Focus Spectrometer},
author = {Charles Fisher and Chaz Morantz and David Braun and Michael Seiffert and Hrand Aghazarian and Eamon Partos and Matthew King and Larry Hovland and Mark Schwochert and Joel Kaluzny and Christopher Capocasale and Andrew Houck and Johannes Gross and Dan Reiley and Peter Mao and Reed Riddle and Khanh Bui and David Henderson and Todd Haran and Rob Culhane and Daniele Piazza and Eric Walkama},
journal= {arXiv preprint arXiv:1408.2833},
year = {2015}
}