The Gran Telescopio Canarias (GTC) primary mirror control system is responsible for making the 36 segments behave like a monolithic mirror. It deals with 108 positioners giving 3 degrees of freedom to each segment, 168 position sensors installed between adjacent segments measuring nanometrical displacements, 216 actuators controling the figure of each segment creating torques, 216 load cells quantifying the applied deforming forces and 216 PT100 monitoring the primary mirror temperature gradient to predict structural dilatations. It provides simple engineering access to all functionalities of each device as well as real time capabilities required to work in closed-loop. All the critical parameters can be monitored from any observatory's workstation thanks to the fully embedded distributed environment included in the control system framework. Hardware interfaces as VME, CAN field buses are fully transparent for the user thanks to the Java front-end (Inspector) that allows to start, control and turn-off each part of the system with a simple mouse click.

Date Published: 14 July 2008
PDF: 12 pages
Proc. SPIE 7019, Advanced Software and Control for Astronomy II, 70190I (14 July 2008); doi: 10.1117/12.789382

Published in SPIE Proceedings Vol. 7019:
Advanced Software and Control for Astronomy II
Alan Bridger; Nicole M. Radziwill, Editor(s)