Behavioral programming of autonomous characters based on probabilistic automata and personality

This paper presents a system for realistic behavioral programming of virtual characters, based on personality and probabilistic automata. We describe personality by using the Five‐Factor Model and achieve autonomy through a goal‐oriented approach. Each character perceives the surrounding world, decides how to behave and acts on the environment according to its personality and to its goals. The chief idea explored by the proposed approach is that personality has a probabilistic influence on behavior selection instead of a deterministic one. Different behavior sequences available to achieve a goal are modeled using probabilistic automata and making probability dependent on character personality. This leads to non‐repetitive behaviors, whose evolution is not foreseeable. The paper first motivates the approach in the context of cybertherapy. Then, it summarizes related work and illustrates in detail the proposed approach. Finally, it presents obtained results and discusses the main limitations of the implemented system. Copyright © 2004 John Wiley & Sons, Ltd.

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