Analysis of GeMS tip-tilt on-sky data: LQG implementation for vibration rejections - Archive ouverte HAL Accéder directement au contenu
Communication Dans Un Congrès Année : 2015

Analysis of GeMS tip-tilt on-sky data: LQG implementation for vibration rejections

Analyse des données ciel tip-tilt de GeMS : Implémentation d'un contrôleur LQG pour la correction des vibrations

Résumé

Adaptive Optics (AO) systems aim at detecting and correcting for optical distortions induced by atmospheric turbulences on ground based telescopes astronomical images. They are also extremely sensitive to extraneous sources of perturbations such as vibrations, which degrade their performance. A new well defined vibration at 37Hz has been detected in January 2015 and is still currently affecting the Gemini South telescope secondary mirror. We show how its existence limits the performance of the operational systems at Gemini South: The Gemini Planet Imager (GPI) and the Gemini Multi-Conjugated AO system (GeMS). We further focus on how these vibrations are affecting GeMS performance and propose to implement the Tip-Tilt control strategy first tested on CANARY and routinely used on SPHERE. It combines identification of a sum of auto-regressive models of order 2 with a Linear Quadratic Gaussian (LQG) control. LQG is now routinely used for Tip-Tilt and focus control for GPI and has been successfully tested on all modes on CANARY. We show that the expected gain in performance brought by this LQG Tip-Tilt control strategy on GeMS compared with an Integral Controller is on the order of 15 to 20mas. The analysis was conducted in "replay mode" using GeMS Tip-Tilt on-sky data. This allows realistic performance assessment before implementation inside the Real-Time Computer (RTC) of GeMS and on-sky tests during the first semester of 2016.
Fichier principal
Vignette du fichier
eScholarship UC item 4h03k92b.pdf (1.22 Mo) Télécharger le fichier
Origine Fichiers produits par l'(les) auteur(s)

Dates et versions

hal-04023215 , version 1 (10-03-2023)

Identifiants

Citer

Lucie Leboulleux, Gaetano Sivo, Rémy Juvenal, Caroline Kulcsár, Vincent Garrel, et al.. Analysis of GeMS tip-tilt on-sky data: LQG implementation for vibration rejections. Adaptive Optics for Extremely Large Telescopes IV (AO4ELT4), Oct 2015, Los Angeles (CA), United States. ⟨10.20353/K3T4CP1131621⟩. ⟨hal-04023215⟩
31 Consultations
18 Téléchargements

Altmetric

Partager

Gmail Mastodon Facebook X LinkedIn More