Research During the course of studying at the University of Toronto, I conducted research in the area of computer animation and artificial life. My research is mainly concerned with physics-based modelling, modelling and control of reactive behaviour and behavioural animation. (For more information about behavioural animation, see the home page of Craig Reynolds . Craig pioneered this field of research and I was fortunate to have the chance to work with him at SGI for a year).

Through exploring the interplay of locomotion, perception, and behaviour in animals, I developed an animation framework that can achieve the intricacy of motion evident in certain natural ecosystems with minimal input from the animator. The realistic appearance, movement, and behaviour of individual animals, as well as the patterns of behaviour evident in groups of animals fall within the scope of this framework.

The framework is validated by a virtual marine world inhabited by a variety of artificial fishes with a repertoire of realistic behaviour. These artificial fishes are autonomous agents with deformable bodies actuated by internal muscles, with eyes, and with minds including perception, motor control and intention/behaviour centres. They explore their habitat in search of food, navigate around obstacles, contend with predators, and indulge in courtship rituals to secure mates. Their behavioral repertoires rely on simulated visual perception in a highly unpredictable and sometimes hostile world.

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This artificial fish system has been further expanded by incorporating active vision and locomotion learning abilities to the fish.
The fishes have earned some fame and were reported in several newspaper and magazine articles, and books. To name a few:
"Fishes of the Silicon Sea" , an articleby Gene Levinson, was published in the June 1995 issue of The World and I .
"These fish swim, feed, flee danger and indulge in courtship; yet they exist only in a computer", was in The Daily Telegraph , England, August, 22ed, 1994.
"Artificial Fish: Virtual fish are the catch of the day" was in The Globe and Mail , Canada, Sept., 10th, 1994.
"Fishes and silicon chips", description and color plates of our work in " Frontiers of Complexity: The Search for Order in a Chaotic World " , by P. Coveney and R. Highfield, Ballantine Books, New York, 1995.
Description and images in Climbing Mount Improbable , by R. Dawkins, Viking, 1996.

Xiaoyuan Tu