Adaptation and Learning in Animated Creatures �

This paper is concerned with synthetic agents in� teracting with virtual environments � called ani� mated creatures. The animated creatures are ar� ticulated graphical �gures that are equipped with a set of primitive behavioral patterns. These pat� terns qualitatively specify which body modules will move concurrently � hence forming a motion group � and which group will move prior to an� other. The parameterization of these patterns is carried out by the creatures given certain exter� nal stimuli. The key to such behavioral adapta� tion lies in an embedded evolution strategy based selection mechanism. Two examples will be given where this selection mechanism enables a bipedal creature and a six�legged creature to dynamically search for the exact positions as well as dura� tion of body joints as constrained by the quali� tatively de�ned gait patterns. The acquired new stimulus�response pairs are recorded and inserted into a behavioral conditioning network which can be reused and re�ned during future movements