SINGLE-INPUT SINGLE-OUTPUT H-INFINITY-CONTROL WITH TIME-DOMAIN CONSTRAINTS

Standard Eta(infinity) optimization cannot handle specifications or co nstraints on the time response of a closed loop system exactly. In thi s paper the problem of Eta(infinity) optimization subject to time doma in constraints over a finite horizon is considered. Following an idea from Helton and Sideris (1989, IEEE Trans. Aut. Control, AC-3.4, 427-4 34) the problem is transformed into a finite dimensional optimization program that is shown to be convex although generically nondifferentia ble. The objective function is constructed via state space methods and several properties of the optimal constrained controller are discusse d together with a robust algorithm for computation. It is shown how sa tisfying the constraints over a finite horizon can imply overall good behavior.