Mt Abu 2.5m Telescope: Design And Fabrication

AMOS S.A. is in charge of the development and installation of a 2.5 m telescope for Physical Research Laboratory (PRL) of India. It is a 20 m focal length Ritchey Chretien Cassegrain configuration equipped with active optics.AMOS has acquired in more than 30 years a large experience in design, analysis, fabrication and commissioning of 2 to 4 m-class telescopes. Strong of this experience, the multidisciplinary integrated team of the project was able to design the Mt ABU 2.5-m telescope in one year with a great mastering of the technologies and sub-systems development which are used. This is the key point for the risk management of the project.In this paper is presented the overall design of the telescope. This includes the optical design, the opto-mechanical design of the mirror supports and, in particular the active primary mirror support, the mount design and the control system for which AMOS has developed a main axes servo control based on industrial programmable logic controller (PLC). The closed loops sensing devices (wavefront sensor and guider) and their associated control systems are also presented. The Assembly, Integration and Verification (AIV) activities are finally discussed.