New Concepts in Lightweight Arms

Abstract

The conflict in designing a robot which is fast for large motions and small motions as well as accurate can be alleviated by strategies of operation such as the one described in this paper, called the bracing strategy. Large motions are assigned to joints which move the major links. When these motions are completed the arm is "braced" against the workpiece or a passive workbench. The small motions are assigned to other degrees of freedom which are referenced to the workpiece rather than the base of the robot. In this way lighter arms are possible without their disadvantages for fast, accurate small motions. The concept and issues of its implementation are discussed.