Artificial Mind for Virtual Characters

This chapter discusses guidelines and models of Mind from Cognitive Sciences in order to generate an integrated architecture for an artificial mind that allows various behavior aspects to be simulated in a coherent and harmonious way, showing believability and computational processing viability. Motivations are considered the quantitative, driving forces of the action selection mechanism that guides behavior. The proposed architecture is based on a multi-agent structure, where reactive agents represent motivations (Motivation Agents) or actions (Execution Agents), and cognitive agents (Cognition Agents) embody knowledge-based attention, goal-oriented perception and decision-making processes. Motivation Agents compete for priority, and only winners can activate their corresponding Cognition Agents, thus filtering knowledge processing. Active Cognition Agents negotiate with each other to trigger a specific Execution Agent, which then may change internal and external states, displaying the corresponding animation. If no motivation satisfaction occurs, frustration is expressed by a discharge procedure. Motivations intensities are then accordingly decreased.