Multi-input multi-output identification for control of adaptive optics systems

In this paper, modern subspace identification methods are applied to a Multi-conjugate Adaptive optics Demonstrator, MAD, developed at ESO. The identified multi-input multi-output systems mapping voltages into slopes can be obtained on data taken in open/closed loop on beacon and in both SCAO and GLAO configurations. The advantages of the proposed approach is twofold: on the one hand the experiment to collect the data takes only few minutes during day time, it can be done on beacon, and all the computational effort is moved off-line. On the other hand, subspace identification provides the mathematical model necessary to design modern model-based controllers (e.g. linear quadratic control).