  This paper introduces an add-on, supervisory scheme, referred to as Action
Governor (AG), for discrete-time linear systems to enforce exclusion-zone
avoidance requirements. It does so by monitoring, and minimally modifying when
necessary, the nominal control signal to a constraint-admissible one. The AG
operates based on set-theoretic techniques and online optimization. This paper
establishes its theoretical foundation, discusses its computational
realization, and uses two simulation examples to illustrate its effectiveness.
