Waffle mode mitigation in adaptive optics systems: A constrained Receding Horizon Control approach

The wavefront sensors that are used in adaptive optics to sense the atmospheric turbulence have blind modes. One of those unseen modes, a waffle mode, occurs as a wavefront perturbation that produce a null or very small measurement on the wavefront sensor. In this paper we discuss a way of waffle mode mitigation by setting additional constraints in the Receding Horizon Control. The results on numerical simulations are presented. The increase in the computational load with the values of constraints is estimated. Output disturbance rejection performance for the constrained case is evaluated. Our numerical simulations suggest that the constrained receding horizon controller is feasible with present day computational capabilities for small and medium-sized adaptive optics systems.