Representing and Visualizing Articulated Movement

Abstract

This thesis develops a representation and system of operations for articulated limb movement which can be used to describe both specific and general movements. A movement primitive in the representation can be described by the angle, axis, and accelerations of a joint rotation and may be combined with other movement primitives to create a new primitive or a sequence of primitives that simultaneously operate on the joints of a limb. The movement representation in this thesis provides a system for defining symbolic representations of movements. This system includes structured types for a single joint rotation, the sequencing of multiple joint rotations, and a limb model. To validate the system, an interactive environment with an integrated visualization of a body model has been developed. The environment is embedded in the Clojure programming language, a Lisp dialect that runs on the Java Virtual Machine. The jME scene graph based graphics engine is used to render the body model and visualize movement. The body model is constructed of mesh cylinders for body segments and graph nodes as joints. The environment allows a user to define movements, perform operations on movements, and apply a movement to the body model and view the effect in real time. Two complex movement examples are provided.