Scripting Facial Expressions for X3D/VRML-based Embodied Agents

This paper proposes a scripting approach to facial animations for embodied agents, in particular for X3D/VRML-based web agents. The use of a scripting technology to control facial expressions has the advantage that it results in highly flexible components; not only can scripts be re-used to define a wide range of facial animation scenarios, but they can also be applied with appropriate parameterization for different application contexts and different agents, despite the fact that agents may have different 3D facial geometrical data. The proposed approach has been implemented as an extention of STEP, a scripting language for embodied agents, by using the distributed logic programming language DLP. In the DLP language framework, a facial model as well as the animation engine are webbased and animation results can be viewed locally in a browser. In addition, facial animations in STEP can be generated on-the-fly, which is a requirement for web-based embodied agents that need to interact with users and other agents in real time. CR Categories: H.5.1 [Multimedia Information Systems]: Animations; H.5.3 [Group and Organization Interfaces]: Web-based interaction; I.2.11 [Distributed Artificial Intelligence]: Intelligent agents