Introduction

Abstract

Rigid-body dynamics is an old subject that has been rejuvenated and transformed by the computer. Today, we can find dynamics calculations in computer games, in animation and virtual-reality software, in simulators, in motion control systems, and in a variety of engineering design and analysis tools. In every case, a computer is calculating the forces, accelerations, and so on, associated with the motion of a rigid-body approximation of a physical system.