Time-optimal trajectory planning for robot manipulators based on the distortive configuration space method

This paper presents an approach to plan obstacle avoiding path of time-optimal trajectory for robot manipulator. When it is assumed that initial and final postures of the manipulator are specified and the manipulator is in the stationary state in both postures, the trajectory minimizing the motion time from the initial state to the final without any collisions against obstacles is planned. In previous papers, time-optimal trajectory along the specified path is well researched and several methods are reported. In this paper, a method to generate the collision free path for time-optimal trajectory is described. It is generally known well that it is effective to utilize Configuration Space for collision free path planning. Then, we propose the method using an advanced configuration space, the Distortive Configuration Space Method, to plan the path. When the configuration space has been obtained, it is transformed with artificial potentials into the distortive one. The path for time-optimal trajectory is represented by a straight segment in the distortive space.