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Practical Character Physics for Animators
July/August 2011 (vol. 31 no. 4)
pp. 45-55
Ari Shapiro, Institute for Creative Technologies
Sung-Hee Lee, Gwangju Institute of Science and Technology
Web Extra: View Supplemental Video
To significantly improve the visual quality of certain types of animated 3D character motion, a proposed graphics system infers physical properties and corrects the results by using dynamics. The system visualizes these physical characteristics and provides information not normally available to traditional 3D animators, such as the center of mass, angular momentum, and zero moment point. By comparing the original path generated by an animator to a proper physically based path generated by the system, animators can interactively modify the original path to more closely match the system-generated path. This often produces better character motion. Users can adjust two types of motion: animations involving ballistic paths, such as falling and jumping, and animations involving movement requiring balance and posture, such as walking or running. A professional software system integrates this method for use in a visual effects studio that incorporates live action with 3D animated characters in feature films. Research shows that from 10 to 16 percent of the shots of a character-heavy feature film will incorporate ballistic motions that the system might improve. The Web extra is a video demonstrating an interactive system that helps animators create physically plausible character motions. You can also view the video on YouTube here: http://www.youtube.com/watch?v=-0OhS6Y5YX4

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Index Terms:
physical simulation, character animation, computer graphics, graphics and multimedia
Citation:
Ari Shapiro, Sung-Hee Lee, "Practical Character Physics for Animators," IEEE Computer Graphics and Applications, vol. 31, no. 4, pp. 45-55, July-Aug. 2011, doi:10.1109/MCG.2010.22
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