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UCLA Adds Physics to Prat-falls
BaltoAaron writes "CNN.com is reporting on Petros Faloutsos , a UCLA scientist, that has developed a program that creates animation based almost solely on physics. Faloutsos "believes his animation program will one day allow virtual stunt artists to replace their flesh-and-blood counterparts in performing otherwise deadly feats of derring-do." "It's the Holy Grail of character animation. Everybody wants to do it, but there's not a whole lot of it out there right now.""
DANCE is a portable, open, plug-in based, object-oriented software package for physics-based character animation. It runs on Linux, Irix, Windows 98/NT and is being ported to MacOS by Joe Laszlo. One of its goals is to provide researchers with a common platform where they can test their control methods and share their results. In addition, it provides the common, yet complex functionality that everyone needs in a physics-based animation system, allowing researchers to concentrate on their research work. Dance has been used for a variety of physics-based applications that include biomechanics modelling and composeable controllers. For more information, please contact the authors.
It's available to download and play with!
Physics-based animation has been a hot topic in computer graphics for a decade. SIGGRAPH made a major award to Prof. Andy Witkin of Carnige Mellon in 2001 for major progress in this field. This involves anmal motions, objects colliding, objects shattering (e.g. Phantom Menace) and so on.
Every computer generted graphic movie thus far has failed
Uh... Toy Story I/II, Bugs Life, Monster's Inc, Shrek, Antz (which I think sucked but did good business)... I wouldn't exactly call them failures.
Well, the trouble with using it to replace stuntmen has as much to do with the realism of actual footage of an event vs a cgi simulation of one.
That is, there are many other factors that cgi imagery comes no where close to mimicking, so even if tommorow this software let you create completely realistic human animation, it wouldn't put the union out of business yet.
Many of the more spectacular stunts in our favorite action movies...such as the ones in crouching tiger...used the computer simply to composite the scene elements (like replacing the ropes from the flying harnesses), rather than recreate the scene. Or that train crash in Die Hard 3. The computer is often used to combine several "real" footages (like combining the actors on one set and the dangerous stuff on another) rather than do a whole scene, anyway.
However, games could be great with this tech. I have always wanted to see a realistic fighting game, one with actual full physics animation, medical grade damage modeling (and when someone is hurt, realistic degradation of their performance), and the completely unscripted movements that an animation engine like this would allow.
For instance, if someone punched your on screen avatar in the gut, your character would first stagger with the blow, and then shake back and forth as he tries to catch his breath. If you hit one of the attack commands at that moment, the subsequent attack animation would be modified by him still recovering from the blow, as WELL as what the other player was doing. A compltely freeform system. Yes, I know its possible to fake some of this now but there are some obvious limits. For instance, no matter how hard or how light your avatar got punched, he will probably still stagger with the same animation.
And of course the "beowolf cluster" of all these technologies : a massively multiplayer online game where you can run around fighting other avatars like above, as well as casting spells, killing monsters, leveling, looting, camping, kill stealing... All the rest of the good things we come to expect from games of this type
Of course, there are definite advantages to putting sensors on someone's body.
If I fall down the stairs, what's going to happen to, say, my right arm, wrist, and hand? Sure, if I'm unconscious, that will all be dictated by physics - I'll flop around like a rag doll and you can nicely see all the reactive forces at work.
But if I'm conscious, how is the programming going to emulate my increasingly desperate attempts to keep from breaking my neck?
It seems to me that a better effect would be captured simply by hooking up motion sensors to a stuntman, telling him to take a five-minute break, and then throwing him down the stairs when he wasn't looking. The "mechanics" realm of physics has relatively simple rules; panic does not. So far, we don't have any formulas for the interaction of perceived danger, temperament, adrenaline, and what have you.
"Beware he who would deny you access to information, for in his heart he deems himself your master."
Sorry, but you are not very clued in on the
research. Petros did not make a physical
simulation of a human walking. That had been
done many years earlier. Researchers at
Georgia Tech [Hodgins, et al.] and U Penn
[Badler, et al.] have focused on simulated
humans since the early 90's, simulating motions
from running to bicycling to diving.
Petros's work was on integrating these motions
together: so a character could walk, trip,
dive, land, roll, and stand back up again.
He used support vector machines to learn
the domains of acceptable pre- and post-
conditions of different movements and plan
the transitions.