Improv is a system designed by Ken Perlin for authoring autonomous characters. It consists of a Behavior Engine and an Animation Engine. The Behavior Engine allows the author to write simple scripts that help the characters make meaningful decisions. The Animation Engine is rather unique. Each animation is defined as a collection of pairs of the most extreme angles that bones are allow to be rotated in. The engine then interpolates the rotation of each bone seperately, with a fair bit of randomness (also defined by the author), between its two extremes. The result is smooth motion that never repeats itself and is surprisingly expressive. It’s a fascinating approach to animation that merits a lot more research and application. Sadly, Mr. Perlin has patented his “invention” so we shouldn’t hold our breath for any revolution in computer animation.
His website contains several examples of Improv-like animations.
And this document explains the project very well.
Posted on June 8, 2006 at 10:09 pm
It should be added that Athomas Goldberg was Ken’s collaborator throughout the development of Improv. Athomas went on to form Improv Technologies, which folded after a few years, and then became head of gaming tech at Sun.
Improv itself is by now somewhat outdated (although the noise technique is of course still useful and in use in various systems); but Ken’s work over the past few years on more sophisticated procedural animation for virtual human actors is very relevant, and what’s sorely missing from the middleware offerings out there.
http://www.naturalmotion.com is one of the few tech companies making progress in realtime procedural virtual human animation.