Modeling and Control of a Large Deformable Mirror

Abstract: The current generation of earth-based telescopes has been of great use to astronomers for the past decades. New fields of astrophysics like the search for and analysis of earth-like planets would however need telescopes with even better resolution. These telescopes are called Extremely Large Telescopes and an ongoing project to develop such a telescope is the Euro50 project. For the Euro50 telescope to achieve enough resolution it will need an adaptive optics system with a large deformable secondary mirror to compensate for atmospheric disturbances. This will make the telescope images sharper. The shape control for such a large mirror requires a dynamic control approach. Since no real mirror was at hand, a modal state space model of the mirror was developed and controlled in the Matlab/Simulink environment. The final MIMO controller uses a combination of state feedback control and compensation filters.\\ \\ This thesis was made in cooperation with Lund Observatory (Lund University), the Department of Automatic Control and the Department of Industrial Electrical Engineering and Automation (Lund Institute of Technology).