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The control system of a distributed aperture imaging testbed / Mel Ni in IEEE Transactions on control systems technology, Vol. 18 N° 6 (Novembre 2010) 

Public ISBD [article]  in IEEE Transactions on control systems technology > Vol. 18 N° 6 (Novembre 2010) . - pp. 1338-1344 Titre : The control system of a distributed aperture imaging testbed Type de document : texte imprimé Auteurs : Mel Ni, Auteur ; Jean-Noel Aubrun, Auteur ; Mike Bishop, Auteur Année de publication : 2011 Article en page(s) : pp. 1338-1344 Note générale : Génie Aérospatial Langues : Anglais (eng) Mots-clés : Active  optics  control  system  Distributed  aperture  Fizeau  imaging  system  Multiple  telescope  array  Phased  array  telescope Index. décimale : 629.1 Résumé : Star-9 is an experimental demonstration of distributed-aperture imaging built at the Lockheed Martin Advanced Technology Center. White light from a scene generator enters an array of nine telescopes and is combined at a focused image plane. Relative aberrations from each telescope are regulated by a control system using phase diversity and active relay mirrors. A Weiner filter is applied to the image, and the resulting angular resolution and image quality are nearly diffraction-limited with the diameter of the array. The control system takes estimates from the phase diversity algorithm and uses them to command mirrors to adjust tip, tilt, and piston in each telescope. Each active mirror has inductive position sensors for local position control. The mirrors are actuated by picomotors and inchworm motors. In addition to tip/tilt/piston errors, the control system is equipped to correct for pupil geometry and rotation errors, and to perform field of regard steering. In this paper, we present details on the control system's local sensing, control law synthesis, and precision actuation methodology. We also describe the incorporation of phase diversity and automated phasing algorithms with the control system and give performance results. DEWEY : 629.1 ISSN : 1063-6536 En ligne : http://ieeexplore.ieee.org/xpl/freeabs_all.jsp?arnumber=5393014 [article] The control system of a distributed aperture imaging testbed [texte imprimé] / Mel Ni, Auteur ; Jean-Noel Aubrun, Auteur ; Mike Bishop, Auteur . - 2011 . - pp. 1338-1344. Génie Aérospatial Langues : Anglais (eng) in IEEE Transactions on control systems technology > Vol. 18 N° 6 (Novembre 2010) . - pp. 1338-1344 Mots-clés : Active  optics  control  system  Distributed  aperture  Fizeau  imaging  system  Multiple  telescope  array  Phased  array  telescope Index. décimale : 629.1 Résumé : Star-9 is an experimental demonstration of distributed-aperture imaging built at the Lockheed Martin Advanced Technology Center. White light from a scene generator enters an array of nine telescopes and is combined at a focused image plane. Relative aberrations from each telescope are regulated by a control system using phase diversity and active relay mirrors. A Weiner filter is applied to the image, and the resulting angular resolution and image quality are nearly diffraction-limited with the diameter of the array. The control system takes estimates from the phase diversity algorithm and uses them to command mirrors to adjust tip, tilt, and piston in each telescope. Each active mirror has inductive position sensors for local position control. The mirrors are actuated by picomotors and inchworm motors. In addition to tip/tilt/piston errors, the control system is equipped to correct for pupil geometry and rotation errors, and to perform field of regard steering. In this paper, we present details on the control system's local sensing, control law synthesis, and precision actuation methodology. We also describe the incorporation of phase diversity and automated phasing algorithms with the control system and give performance results. DEWEY : 629.1 ISSN : 1063-6536 En ligne : http://ieeexplore.ieee.org/xpl/freeabs_all.jsp?arnumber=5393014