Kinematic Analysis of Manipulators Using the Zero Reference Position Description

Abstract

This paper presents a new method ofkinematic analysis of manipulators, called the zero reference position method. In this method, the description of the manipulator is in terms of the axes directions and locations in the zero reference posi tion. This position is a conveniently chosen position in which all joint variable values are defined to be zero. This type of manipulator description is easy to learn and is not prone to errors of interpretation. The governing kinematic equations of the manipulator are derived from the principle of similarity. In this paper, it is shown that this method leads to a modular approach to the closed-form solutions of manipulators with ordinary or geared three-roll wrists. Complete solutions for six types of contemporary industrial robots are included.