Semantics for virtual humans

Population of Virtual Worlds with Virtual Humans is increasing rapidly by people who want to create a virtual life parallel to the real one (i.e. Second Life). The evolution of technology is smoothly providing the necessary elements to increase realism within these virtual worlds by creating believable Virtual Humans. However, creating the amount of resources needed to succeed this believability is a difficult task, mainly because of the complexity of the creation process of Virtual Humans. Even though there are many existing available resources, their reusability is difficult because there is not enough information provided to evaluate if a model contains the desired characteristics to be reused. Additionally, the knowledge involved in the creation of Virtual Humans is not well known, nor well disseminated. There are several different creation techniques, different software components, and several processes to carry out before having a Virtual Human capable of populating a virtual environment. The creation of Virtual Humans involves: a geometrical representation with an internal control structure, the motion synthesis with different animation techniques, higher level controllers and descriptors to simulate human-like behavior such individuality, cognition, interaction capabilities, etc. All these processes require the expertise from different fields of knowledge such as mathematics, artificial intelligence, computer graphics, design, etc. Furthermore, there is neither common framework nor common understanding of how elements involved in the creation, development, and interaction of Virtual Humans features are done. Therefore, there is a need for describing (1) existing resources, (2) Virtual Human's composition and features, (3) a creation pipeline and (4) the different levels/fields of knowledge comprehended. This thesis presents an explicit representation of the Virtual Humans and their features to provide a conceptual framework that will interest to all people involved in the creation and development of these characters. This dissertation focuses in a semantic description of Virtual Humans. The creation of a semantic description involves gathering related knowledge, agreement among experts in the definition of concepts, validation of the ontology design, etc. In this dissertation all these procedures are presented, and an Ontology for Virtual Humans is described in detail together with the validations that conducted to the resulted ontology. The goal of creating such ontology is to promote reusability of existing resources; to create a shared knowledge of the creation and composition of Virtual Humans; and to support new research of the fields involved in the development of believable Virtual Humans and virtual environments. Finally, this thesis presents several developments that aim to demonstrate the ontology usability and reusability. These developments serve particularly to support the research on specialized knowledge of Virtual Humans, the population of virtual environments, and improve the believability of these characters

Migrating characters: effective user guidance in instrumented environments

The work at hand deals with the conceptual design as well as with the realization of virtual characters, which, unlike previous works in this research area, are not limited to a use in virtual worlds. The presented Migrating Character approach on the contrary allows virtual characters to act and interact with the physical world. Different technical solutions allowing a Migrating Character to move throughout physical space, either completely autonomously or in conjunction with a user, are introduced and discussed as well as resulting implications for the characters behavior. While traditional virtual characters are acting in a well defined virtual world, Migrating Characters need to adapt to changing environmental setups in a very flexible way. A Migrating Character must be capable of determining these environmental changes by means of sensors. Furthermore, based on this data, an adequate adaptation of the characters behavior has to be realized. Apart from a theoretical discussion of the necessary enhancements of a virtual character when taking the step from virtual to real worlds, different exemplary Migrating Character implementations are introduced in the course of the work.Die vorliegende Arbeit beschäftigt sich mit dem konzeptuellen Entwurf und der technischen Realisierung von virtuellen Charakteren, die im Gegensatz zu bisherigen Arbeiten auf diesem Gebiet nicht auf den Einsatz in virtuellen Welten beschränkt sind. Der vorgestellte Migrating Character Ansatz erlaubt virtuellen Charakteren vielmehr in der physikalischen Welt zu agieren und zu interagieren. Verschiedene technische Lösungen, welche es einem Migrating Character ermöglichen sich in der physikalischen Welt autonom bzw. in Abhängigkeit vom Benutzer zu bewegen, sind ebenso Gegenstand der Arbeit wie eine ausführliche Diskussion der daraus für das Verhalten des virtuellen Charakters resultierenden Implikationen. Während sich traditionelle virtuelle Charaktere in einer wohl definierten virtuellen Umgebung bewegen, muss ein Migrating Character flexibel auf sich ändernde Umgebungsbedingungen reagieren. Aus sensorischer Sicht benötigt ein Migrating Character also die Fähigkeit eine sich ändernde physikalische Situation zu erkennen. Basierend auf diesen Daten muss weiterhin eine adäquate Anpassung des Verhaltens des Migrating Characters geschehen. Neben einer theoretischen Diskussion der notwendigen Erweiterungen eines virtuellen Charakters beim übergang von virtueller zu realer Umgebung werden auch exemplarische Migrating Character Implementierungen vorgestellt

Emotions, behaviour and belief regulation in an intelligent guide with attitude

Abstract unavailable please refer to PD

Human-Computer Interaction

In this book the reader will find a collection of 31 papers presenting different facets of Human Computer Interaction, the result of research projects and experiments as well as new approaches to design user interfaces. The book is organized according to the following main topics in a sequential order: new interaction paradigms, multimodality, usability studies on several interaction mechanisms, human factors, universal design and development methodologies and tools