Results of the ELT M1 position actuators validation campaign

Lorenzo Pettazzi; Babak Sedghi; Andreas Reinacher; Martin Dimmler; Pablo Barriga; Pablo Zuluaga Ramirez; Marc Cayrel; Oliver Dietzel; Michael Ebert; Timo Maier; Andreas Zürcher; Liang Rong; Christoph Stiebel; Pascal Bankovic

doi:10.1117/12.2562594

13 December 2020 Results of the ELT M1 position actuators validation campaign

Lorenzo Pettazzi, Babak Sedghi, Andreas Reinacher, Martin Dimmler, Pablo Barriga, Pablo Zuluaga Ramirez, Marc Cayrel, Oliver Dietzel, Michael Ebert, Timo Maier, Andreas Zürcher, Liang Rong, Christoph Stiebel, Pascal Bankovic

Author Affiliations +

Proceedings Volume 11451, Advances in Optical and Mechanical Technologies for Telescopes and Instrumentation IV; 114511W (2020) https://doi.org/10.1117/12.2562594
Event: SPIE Astronomical Telescopes + Instrumentation, 2020, Online Only

Abstract

The present paper reports on the results of the validation test campaign of the ELT M1 Position Actuators (M1 PACTs). The main function of these actuators is positioning the 798 segments composing the primary mirror (M1) of the ELT with nanometric tracking error over the relatively large stroke of ten millimetres. In order to achieve this challenging goal the PACTs feature an hybrid actuation concept including a spindle drive for large and coarse movements in series with a piezo actuator for fine position adjustments. Active damping techniques are used to ensure robustness and benign dynamic response to perturbations transmitted through the supporting back structure. The design and manufacturing project of the M1 PACTs has recently entered in the final design phase. In this phase extensive validation testing is planned to verify that the final product is fit for purpose throughout its lifecycle. To this end the M1 PACT is first tested in stand-alone mode, with the objective of verifying its performances in a controlled and stable environment and deriving a reliable model of its dynamic response to be exploited for M1 performance estimation. Then several M1 PACTs are integrated in the M1 Test Stand, a small-scale mock-up of the primary mirror of the ELT. In this configuration multiple actuators are driven together to demonstrate relative position control between two segments. On the basis of the obtained results the paper discusses the expected M1 performance and possible control tuning strategies to be used during the commissioning of the ELT in Chile.

Conference Presentation

Citation Download Citation

Lorenzo Pettazzi, Babak Sedghi, Andreas Reinacher, Martin Dimmler, Pablo Barriga, Pablo Zuluaga Ramirez, Marc Cayrel, Oliver Dietzel, Michael Ebert, Timo Maier, Andreas Zürcher, Liang Rong, Christoph Stiebel, and Pascal Bankovic "Results of the ELT M1 position actuators validation campaign", Proc. SPIE 11451, Advances in Optical and Mechanical Technologies for Telescopes and Instrumentation IV, 114511W (13 December 2020); https://doi.org/10.1117/12.2562594

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