Trajectory generation for manipulators based on artificial potential field approach with adjustable temporal behavior

This paper presents a new trajectory generation method of the artificial potential field approach to a real-time motion planning problem. In the artificial potential field approach, the goal is represented by an attractive artificial potential and the obstacles are represented by repulsive ones, so that the robot reaches the goal without colliding with obstacles by using a gradient vector of the potential field. Although this approach is simple and computationally much less expensive than other methods based on the global information on the task space, little attention has been paid to temporal behavior of the generated trajectories such as a movement time from the initial position to the goal and the velocity profile of the end-effector motion. We argue that temporal behavior of the generated arm trajectory should be taken into account within the framework of the artificial potential field approach and introduce a time base generator that determines a dynamic behavior of the arm trajectory as a part of a feedback controller. By synchronizing a time course of the potential function used as an artificial potential field with the time base generator, the temporal behavior of the generated arm trajectory can be adjusted through the time base generator without any change of the potential function to be used