“…On the other hand, the study of systems under discrete controls and disturbances has sparked much interest in recent years as evidenced by the literature on finite alphabet and boolean control [2,14,16,[20][21][22], mixed integer model predictive control [1], and discrete team theory [23], to cite a few. Building on our recent results in which we derived necessary and sufficient conditions for the existence of robustly control invariant hyperboxes [4,18,19], we revisit the question of size of the smallest such invariant sets, when they do exist. In particular, we assess the existing bounds [17,19] on the size of the smallest robustly control invariant hyperbox set, when size is measured in an 'l∞' sense.…”