Nonholonomic Path Planning for Pushing a Disk Among Obstacles

We consider the path-planning problem for a robot pushing an object in an environment containing obstacles. This new variant of the classical robot pathplanning problem has several interesting geometric aspects, which we explore. We focus on the setting where the robot makes a point contact with the object which is assumed to be a unit disk, while the obstacles are assumed to be polygonal. 1 Introduction Nonprehensile manipulation exploits task mechanics to achieve a goal without grasping [5]. Pushing is one important type of nonprehensile manipulation which can allow complex tasks to be performed by simple mechanisms; it may also enable a robot to move parts that are too heavy to be lifted. The mechanics of pushing is studied in [7], where a simple rule is established to qualitatively determine the motion of a pushed object. This analysis has inspired several nonprehensile manipulation algorithms, in particular the design of part feeders to re-orient parts arriving on a conveyor bel..