fxpodcast: SIGGRAPH 2012 - Animation Physics

This week we talk to Alejandro Garcia about how an understanding of physics can help achieve believable animation. Garcia is a professor in the Department of Physics at San Jose State University and will be presenting a course on animation physics at SIGGRAPH 2012 . Some of the diagrams Garcia refers to in the podcast are re-posted here.

Garcia has presented over 30 classes on physics as it applies to animation at the Department of Artistic Development at DreamWorks Animation SKG. His SIGGRAPH course, taking place on Sunday, 5th August from 2pm to 5pm, covers essential topics from physical mechanics to basic bio-mechanics that apply specifically to character animation.

Diagrams mentioned in the podcast

(Left) Even weight on each foot when the center of gravity is centered above them. (Center and Right) Weight shift due to shift of center of gravity towards screen left. Click to enlarge.

Weight force plate graph.

An examples of the Odd Rule for slowing out.
The 'Fourth Down at Half Time' rule in the graph editor.

Momentum changes more slowly so the force is softer, the impact is less jarring.

Elements of a jump from start to apex; the second half, from apex to settle, is similar. The character’s position is measured from its center of gravity.
Forces during a jump when landing.

Example of action-reaction force: Mr. Alpha punching Mr. Beta.

Maintaining balance on an accelerating train.
Rotation in a back somersault.

More information can be found at Alejandro Garcia's Home Page. You can also preview Garcia's SIGGRAPH course notes in this PDF.


Thanks so much for reading our article.

We've been a free service since 1999 and now rely on the generous contributions of readers like you. If you'd like to help support our work, please join the hundreds of others and become an fxinsider member.