Kinematics and Dynamics for Computer Animation

Abstract

In the first phase of computer animation the traditional techniques of animation were brought to the computer resulting in computer animated films where the keyframes were linked by image-based and parametric interpolation. Especially when trying to compute aesthetic human movement it soon became obvious that a more realistic computer animation has to take into account the basic physical properties of the objects and the fundamental physical principles that govern their movement. In algorithmic animation the evolution of the state of a system of objects is not determined by interpolation, but by physical laws given either as algebraic formulae in the simple case or more complicated as set of coupled nonlinear differential equations. In kinematic animation the objects are moved according to a set of given equations for the velocities or the accelerations at certain points of the objects. This procedure results in a realistic animation only if the prescribed velocities and accelerations were derived from a complete dynamic physical model. Therefore, the most general approach for generating physically correct animation sequences is to perform a full dynamical simulation of the given model taking into account all external and internal forces and torques.