Real-Time Obstacle Avoidance Using Harmonic Potential Functions

This paper presents a new formulation of the artificial potential approach to the obstacle avoidance problem for a mobile robot or a manipulator in a known environment. Previous formulations of artificial potentials, for obstacle avoidance, have exhibited local minima in a cluttered environment. To build an artificial potential field, we use harmonic functions which completely eliminate local minima even for a cluttered environment. We use the panel method to represent arbitrarily shaped obstacles and to derive the potential over the whole space. Based on this potential function, we propose an elegant conml strategy for the real-time control of a robot. We test the harmonic potential, the panel method and the control strategy with a bar-shaped mobile robot and a 3 dof planar redundant manipulator.