ELVA: Conversational agent in an interactive virtual world

Abstract

The technology of Embodied Conversational Agents (ECAs) offers great promise for natural and realistic human-computer interaction. The interaction design in this domain needs to be handled sensitively in order for verbal and nonverbal signals conveyed by the agent to be understood by human users. This thesis describes an integrative approach for building an ECA that is able to engage conversationally with human users, and that is capable of behaving according to social norms in terms of facial display and gestures. The research focuses on the attributes of the agenta??s autonomy and believability. To achieve autonomy, we present a three-layered architectural design to ensure appropriate coupling between the agenta??s perception and action, and to hide the internal mechanism from users. In regard to agent believability, we utilize the notion of a??schemaa?? to support structured and coherent verbal behaviors. We also present our approaches to generate and coordinate the agenta??s nonverbal behaviors, so as to establish social interactions within a virtual world.Using the above approach, we developed Elva, an embodied tour guide that inhabits an interactive art gallery to offer guidance to human users. A user study was performed to assess user satisfaction and agent believability when interacting with Elva. Future work will address the area of affective computing to achieve greater believability.