Simultaneous output feedback H∞ control of p plants using switching

We consider the problem of finding one output feedback controller which achieves H_∞ performance when connected to any one of p linear time invariant plants. The min-max controller for this problem will in general not be based on certainty equivalence. We suggest a switching controller architecture where the switching mechanism is based on the residuals connected to worst-case state estimation for each of the p plants and discuss a smooth approximation of the switching control law.