Exploration of an unknown environment with a differential drive disc robot

This paper addresses the problem of exploring an unknown, planar, polygonal and simply connected environment. A saliency object (i.e. a landmark) is located in the environment. The collision-free subset of the robot's configuration space is simply connected or it might have several connected components. The robot is a differential drive system shaped as a disc. The robot has limited sensing, namely it is incapable of measuring any distance or angle, or performing self localization. The exploration problem consists in discovering the environment with the robot's sensor. To solve this problem, a motion policy is developed based on simple sensor feedback and a complete exploration strategy is represented as a Moore Machine. The proposed exploration strategy guarantees that the robot will discover the largest possible region of the environment. Consequently, the robot will find the landmark or declare that an exploration strategy to find it does not exist.