(Disney Meets Darwin)

1: Introduction

Animation, in the tradition of Disney, is "The Illusion of Life". New computational techniques such as those practiced in the field of artificial life have begun to contribute techniques to the art of animation for the simulation of life. "Life" can mean something quite different to a cartoon animator than it can to a theoretical biologist. I have been exploring these differences, and also the similarities. The ideas described here are derived from recent explorations in applying genetic algorithms to a variety of visual design domains, including character animation [Ventrella 94, 1].

The use of the proper names "Disney", and "Darwin" in the title are not a claim that this work represents the achievements of either individual, but simply to imply that the work applies the concept of natural selection to the art of expressive animation.

How do animators create expressive, humorous motion? It rarely happens in one sweeping act of design, but rather in stages of refinement, involving trial and error, often bringing in techniques which have worked well in the past and combining them with new techniques, or taking aspects of one character and applying them to another. The creative act is quite often an evolutionary process, involving bottom-up emergence, discovery, and serendipity - mixed in with the more understood top-down design schemes. Can the evolutionary aspect of design activities be supported by computational tools?

In this paper I present a system which was built with this question in mind. It is manifest as an experimental evolution-based tool for exploring variations in articulated stick figures, serving as moving-skeletons for three dimensional forms. These figures move in real-time on a computer screen and inhabit a virtual world of simple physics, with gravity, momentum, and friction. Their anatomies and styles of wiggling around come in many varieties, as determined by their genetic makeup, and the ways in which their genes interact with each other and the environment. The genetic component of these figures can evolve in response to an animator's "breeding" activities (interactive evolution), and also by way of automatic evolution - driven by multiple fitness criteria.

2 The Art of Motion

(go to beginning of document)