Name: Nagabhushana Subramanya
Affiliation: Indian Institute of Astrophysics
Conference ID : ASI2022_684
Title : Indian Space Imaging and Spectroscopic Telescope(INSIST) - MECHANICAL SYSTEMS
Authors : Nagabhushana Subramanya, Sandeep DS, S Kathiravan
Abstract Type: Poster
Abstract Category : Instrumentation and Techniques
Abstract : INSIST Mechanical system consists of telescope structure ring (TSR) and an extended boom fixed on it, is the metering structure of the structure. The TSR supports the primary mirror and the secondary mirror is supported at the tip of the boom which is 3.8 m long. The supports for the tertiary mirror and other optical elements are also derived from the boom along its height along the optical path. An enclosing structure is configured around the telescope, made in segments to prevent the stray light and contaminants entering the optical cavity. A baffle is configured on the top of the telescope above the plane of secondary mirror to cut down the stray light and also to serve as sun shield. The TSR and boom is proposed to realise with light weighted titanium alloy. This is to keep the variation in optical separation distances to minimum possible extent during thermal escalations during orbiting. The TSR supports the opto-mechanical elements of spectroscopic channel and detectors right below the primary mirror. The tip of the baffle is called entrance aperture, through which light enters the telescope. A door is proposed at the tip of the EA which limits the contaminants entering the optical cavity. The mechanical envelope of the instrument is about 3.85 x 1.82 x 1.35 m. The bottom portion of the TSR provides interface to a spacecraft adopter ring which provides interface with the spacecraft. Interface between these two systems are thought of in such a way that the deformation or clamping/thermal stress on optical mounts are kept minimum. The whole payload weighs about ~450 Kg, including optics mass. The static, dynamic and response analysis of the system are carried out to optimise global stiffness and mass of various options of the are presented in the paper.