QUATERNIONS AND MOTION INTERPOLATION

Abstract

This paper explains straight-line interpolation of solid object motion, such as robot end effector translation and rotation. Smoothly changing orientation is accomplished using quaternions- a way of representing every orientation as four numbers (an angle and an axis of rotation). The first portion of the paper clarifies quaternions to provide an intuitive understanding of their role in rotation. Interpolation is then discussed, concluding with some problems in real manipulator implementations. The interpolation method has been tested on an Excalibur robot.