  This paper addresses the problem of planning for a robot with a directional
obstacle-detection sensor that must move through a cluttered environment. The
planning objective is to remain safe by finding a path for the complete robot,
including sensor, that guarantees that the robot will not move into any part of
the workspace before it has been seen by the sensor. Although a great deal of
work has addressed a version of this problem in which the "field of view" of
the sensor is a sphere around the robot, there is very little work addressing
robots with a narrow or occluded field of view. We give a formal definition of
the problem, several solution methods with different computational trade-offs,
and experimental results in illustrative domains.
