Model of facial expressions management for an embodied conversational agent

In this paper we present a model of facial behaviour encompassing interpersonal relations for an Embodied Conversational Agent (ECA). Although previous solutions of this problem exist in ECA's domain, in our approach a variety of facial expressions (i.e. expressed, masked, inhibited, and fake expressions) is used for the first time. Moreover, our rules of facial behaviour management are consistent with the predictions of politeness theory as well as the experimental data (i.e. annotation of the video-corpus). Knowing the affective state of the agent and the type of relations between interlocutors the system automatically adapts the facial behaviour of an agent to the social context. We present also the evaluation study we have conducted of our model. In this experiment we analysed the perception of interpersonal relations from the facial behaviour of our agent. © Springer-Verlag Berlin Heidelberg 2007.