Title	Physically Based Modelling and Animation of Rigid Body Systems
Detail	Physical modelling and simulation of bodies is an attractive and increasingly popular method of producing realistic animations. The kinematics and dynamics of particles and rigid bodies are presented in this thesis in a coherent and comprehensive manner, covering all of the classical mechanics necessary to implement a physically based modelling system for either particles or rigid bodies. This basis in physics enables us to solve the forward-dynamics problem of determining the motion of bodies under known forces. Numerical integration techniques are described that are used to solve the equations of motion of the bodies being modelled. Various ways of describing the state of rigid bodies are discussed, with particular reference to the suitability of the methods for use in numerical integration. Methods for detecting collisions between bodies are discussed briefly, and the correct physical response of rigid bodies to colliding contact is described in more detail. Constraints, that restrict the allowed motions of bodies, are discussed, and suitable constraint functions to specify a number of different types of constraint are derived. A general method for finding the forces necessary to maintain a system of constraints is then developed, first for systems of particles, and then for systems of rigid bodies. This is an example of the inverse-dynamics problem of determining the forces required to produce a desired or known motion. Constraints of the form described here are used to provide joints between rigid bodies. All these aspects of rigid body modelling are implemented in a simulation system to demonstrate how animations can be produced using physically based modelling instead of more traditional animation methods.
Authors:	Former member: Robin Otte
Year	1999
URL	http://www.cs.auckland.ac.nz/GG/robin_otte.html

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