Abstract 114

Submitted by Javier BARRIGA

Authors

J. M. Casalta(1), J. J. Barriga(1), L. Jochum(2), E. Vernet(2), N. Hubin(2), M. Dimmler(2), M. Mueller(2),

Affiliations

(1)Instruments and Systems Division, NTE,S.A.(Spain); (2)European Southern Observatory (Germany)

Abstract

The E-ELT M5 Field Stabilization Unit (M5FU) is a fast correcting optical system that shall provide tip-tilt corrections for the telescope dynamic pointing errors and for the effect of atmospheric tip-tilt and wind disturbances. NTE (S) is in charge of building a M5FU Scale 1 Demonstrator (M5FU1D) and developing the conceptual design of the final unit, under ESO contract and supported by CSEM and SAGEM subcontractors. The M5FU1D is being built to assess the feasibility of the key elements (actuators, sensors, mirror, mirror interfaces) and the real-time control algorithm. The strict constraints (e.g. Tip-tilt bandwidth 100Hz, 3 meter ellipse mirror size, Mirror first Eigen frequency 300Hz, maximum range ± 150 μrad, maximum tip-tilt error < 200 nrad, power dissipation and the location of the control unit further away of 300 meters from the mirror) have been a big challenge for developing the M5FU1D. Technologies of SiC (Silicon Carbide), largest piezo actuators, eddy current displacement sensors and seismic accelerometers are needed to achieve such requirements. The paper summarises the development status of the M5FU scale 1 demonstrator and main issues of the final unit conceptual design. Next step to M5FU1D is the execution of the test procedure for the acceptance of the design.