LEMAN: A System for Constructing and Animating Layered Elastic Characters

An interactive animation system is presented for constructing layered character models with simulated elastic components. The system, called LEMAN (Layered Elastic Model ANimation), allows three-dimensional animated characters to be built up from successive layers of skeleton, muscle, fat and skin in a completely interactive, direct-manipulation environment, using a variety of input devices. Using an artist's anatomical approach, the character is represented as a simulated elastically deformable skin surface which is wrapped around a kinematically modeled articulated figure. It may then be animated by moving the underlying articulated figure, either interactively using forward or inverse kinematics, or by interpolating a sequence of key postures. Once a motion sequence has been specified, the entire simulation can be recalculated at a higher surface resolution for better visual results. Although the system is most practical for animating relatively simple cartoon-like characters, the realistic-looking shapes and movements resulting from the physical simulation make it well-suited for research into naturalistic human and animal animation.