Conference Paper

On the beat!: timing and tension for dynamic characters.

DOI: 10.1145/1272690.1272723 Conference: Proceedings of the 2007 ACM SIGGRAPH/Eurographics Symposium on Computer Animation, SCA 2007, San Diego, California, USA, August 2-4, 2007
Source: DBLP

ABSTRACT Dynamic simulation is a promising complement to kinematic motion synthesis, pa rticularly in cases where sim- ulated characters need to respond to unpredictable interactions. Moving b eyond simple rag-doll effects, though, requires dynamic control. The main issue with dynamic control is that there are no standardized techniques that allow an animator to precisely specify the timing of the motion while still providing na tural response to exter- nal disturbances. The few proposed techniques that address this prob lem are based on heuristically or manually tuning proportional-derivative (PD) control parameters and do not gen eralize easily. We propose an approach to dynamic character control that is able to hon or timing constraints, to provide natural- looking motion and to allow for realistic response to perturbations. Our appro ach uses traditional PD control to interpolate between key-frames. The key innovation is that the parameter s of the PD controllers are computed for each joint analytically. By continuously updating these parameters over time, the controller is able to respond naturally to both external perturbations and changes in the state of the char acter.

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