M. S. Thesis Abstract

An Investigation of a Spherical Robot Wrist Actuator

Chi Kong Kwan

December 1987

This thesis describes the design and development of a 3 degree of freedom micro-motion manipulator based on the In-parallel mechanism. Circuit designs are becoming denser and testing techniques are becoming obsolete. Present circuit inspection devices are handicapped since they cannot do a good job with emerging circuit designs. Circuit inspection can be improved when a manipulator which can provide micro-motion is available. Once such manipulator which can aid not only in circuit testing but also in other areas where micro-motion is needed has been developed.

To provide the micro-motion, piezo-electric actuators have been used. The problem of feeding back position information of each link has been tackled and used effectively in link control.

The micro-motion manipulator has been tested out using a very simple but interesting laser beam technique. The experimental analysis has been backed by theoretical analysis. A feeling for the range of motion has been provided.

Finally, an example where the micro-motion manipulator could be coupled with a macro-motion manipulator is given. The macro system chosen in this example was the spherical motor. Inverse kinematic equations have been developed for this macro/micro system.