Handling real-world motion planning: a hospital transport robot

A description is given of a hospital transport mobile robot, HelpMate, developed to carry out such tasks as the delivery of off-schedule meal trays, lab and pharmacy supplies, and patient records. Unlike many existing delivery systems in the industry which operate within a rigid network of wires buried or attached to the floor, a hospital transport robot is expected to be able to navigate much like a human would, including handling uncertainty and unexpected obstacles. The navigation system of HelpMate makes use of the specific structure of a hospital hallway environment and relies on recent results on provable sensor-based motion planning algorithms that specifically address the issue of navigation in an unknown and unstructured environment. Also incorporated in the system are algorithms for handling unmodeled factors such as sensor noise and sensor inaccuracy, errors in position estimation, and moving obstacles (e.g. people).>