  This paper presents a scalable control algorithm that enables a deployed
mobile robot system to make high-level decisions under full consideration of
its probabilistic belief. Our approach is based on insights from the rich
literature of hierarchical controllers and hierarchical MDPs. The resulting
controller has been successfully deployed in a nursing facility near
Pittsburgh, PA. To the best of our knowledge, this work is a unique instance of
applying POMDPs to high-level robotic control problems.
