Collision Avoidance for a Multiple-DOF Manipulator Based on Empty Space Analysis of the 3-D Real World
Hiromu Onda*, Tsutomu Hasegawa**, and Toshihiro Matsui*
* Electrotechnical Laboratory, AIST, MIITI, 1-1-4 Umezono, Tsukuba, Ibaraki 305, Japan
** Department of Computer Science and Communication Engineering, Faculty of Engineering, Kyushu University, Hakozaki 6-10-1, Higashi-ku, Fukuoka 812, Japan
This paper describes a new method for finding collisionfree paths for a multiple-degree of freedom (DOF) manipulator with rotational joints and a grasped object. The method first analyzes the structure of empty space in the 3-D workspace. Based on this space analysis, the path search is divided and direction which appears to be most promising is determined in the 3-D workspace. Finally, the path search is systematically executed in the joint space in the direction equivalent to the promising direction. This method is applicable to various problems regardless of the number of degrees of freedom of the manipulator, its structure, and the presence of a grasped object.