Biblio

Embodied conversational agents are changing the way humans interact with technology. In order to develop humanlike ECAs they need to be able to perform natural gestures that are used in day-to-day conversation. Gestures can give insight into an ECAs personality trait of extraversion, but what factors into it is still being explored. Our study focuses on two aspects of gesture: amplitude and frequency. Our goal is to find out whether agents should use specific gestures more frequently than others depending on the personality type they have been designed with. We also look to quantify gesture amplitude and compare it to a previous study on the perception of an agent's naturalness of its gestures. Our results showed some indication that introverts and extraverts judge the agent's naturalness similarly. The larger the amplitude our agent used, the more natural its gestures were perceived. The frequency of gestures between extraverts and introverts seem to contain hardly any difference, even in terms of types of gesture used.

This paper describes a system for embodied conversational agents developed by Inmerssion and one of the applications—Young Merlin: Trial by Fire —built with this system. In the Merlin application, the ECA and a human interact with speech in virtual reality. The goal of this application is to provide engaging VR experiences that build rapport through storytelling and verbal interactions. The agent is fully automated, and his attitude towards the user changes over time depending on the interaction. The conversational system was built through a declarative approach that supports animations, markup language, and gesture recognition. Future versions of Merlin will implement multi-character dialogs, additional actions, and extended interaction time.