1Use of Finite Element Model and Temperature Measurements for Real Time Control of Active Surface and Pointing of a 50 m Radio Telescope

The Large Millimeter Telescope (LMT) is a 50 m diameter radio telescope with an actively controlled segmented surface to be used for astronomy at millimeter wave lengths. The specifications call for a surface accuracy of 70 micrometers RMS and a pointing accuracy of 0.7 arcseconds RMS. This paper evaluates a proposed approach for computing and correcting in real time the surface deformations of the primary reflector and the pointing errors of the telescope due to thermal deformations using a finite element model and temperature measurements throughout the telescope structure