Simulating the Emotion Dynamics of a Multimodal Conversational Agent

We describe an implemented system for the simulation and visualisation of the emotional state of a multimodal conversational agent called Max. The focus of the presented work lies on modeling a coherent course of emotions over time. The basic idea of the underlying emotion system is the linkage of two interrelated psychological concepts: an emotion axis – representing short-time system states – and an orthogonal mood axis that stands for an undirected, longer lasting system state. A third axis was added to realize a dimension of boredom. To enhance the believability and lifelikeness of Max, the emotion system has been integrated in the agent’s architecture. In result, Max’s facial expression, gesture, speech, and secondary behaviors as well as his cognitive functions are modulated by the emotional system that, in turn, is affected by information arising at various levels within the agent’s architecture.