Implementation with Orccad of a Method for Smooth Singularity Crossing in a 6-DOF Manipulator

摘要

: This paper addresses the problem of kinematics singularity crossing for robot manipulators. The proposed method is based on the task-function approach ([5]) and is quite general. It has already be applied to the simulated case of a simple planar redundant robot ([6]), and we propose here a complete description of its extension to a six degrees of freedom robot. The paper is organized in two main parts. After a brief state-of-the-art, we describe in details the general proposed method. From the control point of view, it relies on the framework of the computer torque approach, expressed in a general way. The control objective is defined under the form of an output regulation problem. This goal can be shown in the present case to correspond to the minimization of a quadratic cost function, which blends a trajectory tracking requirement in translation and orientation and a regularizing term. This last term expresses a "safe" behavior of the robot in the neighborhood of a singularity, and...