Disturbance rejection analysis of LQG control for an adaptive optics system
Jean-Pierre FOLCHER and Marcel CARBILLET
Laboratoire H. Fizeau & UFR Sciences Laboratoire H. Fizeau UMR 6525 Université de Nice Sophia-Antipolis
We analyse the performance of an LQG based controller for an adaptive optics (AO) system. In many AO applications wind velocities and the strength of the distortion of the wavefront can change rapidly, rendering the disturbance prediction far from optimal and degrading the disturbance rejection property of the AO loop. Special attention is given to the choice of the disturbance model to ensure satisfactory disturbance rejection performance despite turbulence variations (wind velocities, strength of distortion wavefront). he proposed approach also serves the trade-off between the accuracy of the prediction and the model complexity to limit the computational cost of the LQG control. The achieved performances are evaluated through numerical experiments using the Software Package CAOS.