Min-max predictive control strategies for input-saturated polytopic uncertain systems

A novel robust predictive controller for input-saturated LTV discrete-time systems with polytopic model uncertainties is presented. The solution is ba sed on the minimization, at each time instant, of an upper-bound of the "wo rst-case" infinite horizon quadratic cost under the constraint of steering the set-valued future state evolutions emanating from the current state int o a feasible and positive invariant set. A condition on the initial state i s given that suffices to ensure problem solvability for all subsequent time instants. Under the latter, the proposed predictive controller is proved t o robustly asymptotically stabilize the input-saturated LTV polytopic syste m. (C) 1999 Elsevier Science Ltd. All rights reserved.