<title>Analysis of path-planning strategies in dynamic computer-vision-guided teleoperation</title>

Abstract

Numerous path planning and collision avoidance techniques have been proposed in the robotics literature. Global techniques provide optimal paths but are not flexible to changes in the environment. Local techniques provide non optimal paths but can adapt quickly to dynamic environments and usually require less computing time. One of the most promising techniques in the second category is the potential field approach. Unfortunately, it is well known that local minima may trap the robot away from its goal. Our work intends to override this drawback and to give full autonomy to a potential field path planning strategy ensuring collision avoidance. This paper presents a study of path planning and collision avoidance strategies and defines a general framework to implement a potential field path planning strategy in an unknown and dynamic environment. Our work is concerned with telemanipulation tasks in hazardous environments such as electricity distribution networks. A volumetric model of the scene is built incrementally from the information provided by a dynamic computer vision setup. It is used to help a human operator in guiding the manipulator without colliding with components of the scene. The impact of various path planning techniques on the behavior of the robot is analyzed as well as the dependency on the volumetric model. Finally, it is shown that potential field techniques can lead to very good performances, especially if they are combined with other appropriate tools such as a reliable model of the environment.