Physically-based Animation of Volumetric Objects

This paper presents a voxel-based animation technique which employs either a massspring model or a nite elementmodel. The voxel-based mesh is generated in a pre-processing step. Two volumetric objects, a voxelized chair and scanned muscle are used as case studies with di erent models. The mass-spring model is used to show an animation sequence of a falling and bouncing chair. Wireframe display and volume rendering are used to display a real-time animation of the process. In addition, a real-time simulation is carried out by Finite Element Method (FEM) of a voxel-based multi-resolution muscle mesh. Two techniques, a direct integration and a simpli ed modal analysis method are discussed in the context of applying FEM for muscle deformation. Local deformation optimization with modal analysis for higher resolution muscle volumetric animation, which allows accurate prediction of muscle deformation changes, has been applied. The physiological muscle force has been considered and a biomechanically-based 3D FEM muscle model has been implemented. Realistic animations have been produced based on the FEM simulation with various graphics techniques.