Optimal Feedback Design for Uncertain Systems: A Time-Domain Fixed-Point Approach in L_∞

This paper considers an alternative to quantitative feedback theory (QFT), an alternative deriving solely from a time-domain setting in Banach space L_∞ and providing both a precise, amplitude-oriented design formulation and a general, computer-oriented design procedure. System dynamics, stability, and tracking are characterized as fixed-point operator equations and conditions under which tracking errors satisfy explicit bounds. The design formulation and procedure are illustrated by two design examples.