2009 Papers

We present recent extensions for the intelligent virtual agent development platform Pogamut 3. These extensions are: the agent coordination language StorySpeak designed for the purposes of storytelling applications, support for gestures based on BML, the visual editor of reactive plans, connection of the cognitive architecture ACT-R, an educational application aimed at orientation in urban areas and finally an emotional model. Read more

For simulating communicative behavior, realistic appearance and plausible behavior is important. Postures and mimics also reflect emotional behavior. There exist various models of emotion, like the psycho-evolutionary theory developed by Plutchik [1], or Ekman's FACS. But most models are only suited for muscular expressions. A more unattended field however, also in graphics, is the change in color. Also, other physiological symptoms like crying are left unconsidered. Read more

Authoring the AI for non-player characters (NPCs) in modern video games is an increasingly complex task. Designers and programmers must collaborate to resolve a tension between believable agents with emergent behaviours and scripted story lines. Behaviour trees (BTs) have been proposed as an expressive mechanism that let designers create complex behaviours along the lines of the story they want to tell. However, BTs are still too complex for non-programmers. In this paper, we propose the... Read more

Social relationships are fundamentally important to humans. Children are born into a family social structure and gradually they become part of a wider social structure including peers, in which each individual's relationships are affected by other relationships. To most people expressing appropriate non-verbal social behaviours when interacting with others in a virtual environment (VE) is natural and effortless as they do so daily in the physical world. There is a minority group, such as people... Read more

In this article we show how socio-psychological status theories can be formalized and used to control the expressive and communicative behavior of intelligent virtual agents. We describe Exstasis, a model that computes the status and action tendencies for all actors in a situation based on their status characteristics and behavior patterns. As a configurable software component Exstasis can be integrated in existing systems to extend the social capabilities of the virtual characters. Read more

Believable spatial behaviour is important for intelligent virtual agents acting in human-like environments, such as buildings or cities. Existing models of spatial cognition and memory for these agents are predominantly aimed at issues of navigation and learning of topology of the environment. The issue of representing information about possible objects' locations in a familiar environment, information that can evolve over long periods, has not been sufficiently studied. Here, we present a novel representation for "what-where"... Read more

Gunslinger is an interactive-entertainment application of virtual humans that transforms an iconic Wild West movie scene into a vivid semblance of reality. The project combines virtual humans technology with Hollywood storytelling and set building into an engaging, mixed-reality, story-driven experience, where a single participant can interact verbally and non-verbally with multiple virtual characters that are imbedded in a real, physical saloon. The Gunslinger project pushes the frontier of virtual humans research by combining question-answering dialogue... Read more

Users expect characters in role-playing games to be proactive and social, but these characters fail to deliver in this respect due to limitations of traditional game AI programming approaches. BDI-based approaches are suited for development of proactive systems, such as NPCs in games. This paper argues that a BDI-based approach is also highly suited for developing social NPCs in a principled way. Read more

Games and Virtual Environments populated with virtual agents are usually tested and evaluated assessing the player's experience and flow outside the game experience. However, with player enjoyment related to their sense of immersion, there is clear potential for immersing evaluation into game play. We have developed an immersive in-role evaluation approach and applied it to ORIENT (Overcoming Refugee Integration with Empathic Novel Technology), a role-playing game designed for intercultural training for 13-14 year olds.... Read more

Although there is progress in modeling and implementing affective phenomena - computation of emotion - the new direction proposed here is to model and represent irrational and subconscious processes, the hidden aspects of the human psyche as analysed by Freud and his successors, and by other disciplines in psychotherapy. The outcome will be a 'psychodynamics engine' that does not simply respond emotionally to context and interaction, but is driven by its own convoluted patterns, triggers and... Read more