On the Design and Construction of Direct-Drive Robots

Abstract

In this research, a statically-balanced direct-drive manipulator is designed and constructed to achieve improved dynamic behavior for compliance control [10, 11, 12]. The manipulator mechanism, incorporating a four-bar linkage, is designed so that its functional parts are balanced in all positions without the addition of counterweights. The motors are never loaded by gravity. As a result, smaller motors with less torque can be used to achieve higher speed, accuracy, and repeatability in fine manipulation tasks. The robot is powered by high-torque AC synchronous motors. The mechanism is comprised of graphite-epoxy and AA7075T6 aluminum materials. The manipulator is controlled by a parallel processor computer.