Estimation of the position of the ELT prefocal station main axis in operation

Le résumé fourni par la source

The Natural Guide Star Adapter (NGSA), a circular structure that is part of the Extremely Large Telescope (ELT) Pre-Focal Station (PFS) [6], defines with its rotation axis one of the reference coordinate systems of the entire telescope and has a key role in the performance of all the instruments. The PFS NGSA hosts three sensor arms (SA), which are free to move in a roughly annulus area to support to support closing control loops on natural guide stars when the light beam is controlled by the telescope[2]. The actuation of these SA’s causes a deformation of the mechanical structure and consequently uncertainty on the position and orientation of the reference coordinate system. Starting from the Finite Element Analysis (FEA) of the PFS, we develop a model that reconstructs the behavior of the structure for all the possible combinations of SA positions, and we conceive strategies for a robust definition of the reference coordinate system, as described in this paper.

Ce résumé expose les affirmations des auteurs. BNTIC ne l’interprète pas comme une validation indépendante des résultats.