Architecture of the metrology for the SRT

Tonino Pisanu; Franco Buffa; Gian Luigi Deiana; Pasqualino Marongiu; Marco Morsiani; Claudio Pernechele; Sergio Poppi; Giampaolo Serra; Giampaolo Vargiu

doi:10.1117/12.925547

17 September 2012 Architecture of the metrology for the SRT

Tonino Pisanu, Franco Buffa, Gian Luigi Deiana, Pasqualino Marongiu, Marco Morsiani, Claudio Pernechele, Sergio Poppi, Giampaolo Serra, Giampaolo Vargiu

Author Affiliations +

Proceedings Volume 8444, Ground-based and Airborne Telescopes IV; 84442E (2012) https://doi.org/10.1117/12.925547
Event: SPIE Astronomical Telescopes + Instrumentation, 2012, Amsterdam, Netherlands

Abstract

The Sardinia Radio Telescope (SRT) Metrology team is planning to install an initial group of devices on the new 64 meters radio-telescope. These devices will be devoted for the realization of the antenna deformation control system: an electronic inclinometer able to monitor the alidade deformations and a Position Sensing Device (PSD) able to map the antenna secondary mirror (M2) displacements and tilts. The inclinometer will be used to map the rail conditions, the azimuthal axis inclination and the thermal effects on the alidade structure. The PSD will be used to measure the secondary mirror displacements induced by the gravity and by the thermal deformations that produce shifts and tilts with respect to its ideal optical alignment. The PSD will be traced by diode laser installed on a mechanically stable position inside the elevation equipment room. The inclinometer has been tested in laboratory with the aim to compare its performances with a reference measurement system. The PSD and the laser have been characterized by a long-term tests to assess their stability and accuracy, thus simulating the open air conditions that will be experienced by the device during its operative life. M2 may move freely in space thanks to a six axis actuator system (hexapod). The PSD measurements are processed by a hexapod kinematic model (HKM) to evaluate the correct actuator elongations, thus closing the control loop. The sensors will be acquired and recorded by a dedicated PC installed in the Alidade equipment room and connected to the sensors via the Ethernet network.

Citation Download Citation

Tonino Pisanu, Franco Buffa, Gian Luigi Deiana, Pasqualino Marongiu, Marco Morsiani, Claudio Pernechele, Sergio Poppi, Giampaolo Serra, and Giampaolo Vargiu "Architecture of the metrology for the SRT", Proc. SPIE 8444, Ground-based and Airborne Telescopes IV, 84442E (17 September 2012); https://doi.org/10.1117/12.925547

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available