Smiling Virtual Characters Corpora

To create smiling virtual characters, the different morphological and dynamic characteristics of the virtual characters smiles and the impact of the virtual characters smiling behavior on the users need to be identified. For this purpose, we have collected two corpora: one directly created by users and the other resulting from the interaction between virtual characters and users. We present in details these two corpora in the article.

Virtual characters designed for forensic assessment and rehabilitation of sex offenders: standardized and made-to-measure

This paper presents two studies pertaining to the use of virtual characters applied in clinical forensic rehabilitation of sex offenders. The first study is about the validation of the perceived age of virtual characters designed to simulate primary and secondary sexual character of typical adult and child individuals. The second study puts to use these virtual characters in comparing a group of sex offenders and a group of non deviant individuals on their sexual arousal responses as recorded in virtual immersion. Finally, two clinical vignettes illustrating the use of made-to-measure virtual characters to more closely fit sexual preferences are presented in Discussion.

XSAMPL3D: An Action Description Language for the Animation of Virtual Characters

In this paper we present XSAMPL3D, a novel language for the high-level representation of actions performed on objects by (virtual) humans. XSAMPL3D was designed to serve as action representation language in an imitation-based approach to character animation: First, a human demonstrates a sequence of object manipulations in an immersive Virtual Reality (VR) environment. From this demonstration, an XSAMPL3D description is automatically derived that represents the actions in terms of high-level action types and involved objects. The XSAMPL3D action description can then be used for the synthesis of animations where virtual humans of different body sizes and proportions reproduce the demonstrated action. Actions are encoded in a compact and human-readable XML-format. Thus, XSAMPL3D describtions are also amenable to manual authoring, e.g. for rapid prototyping of animations when no immersive VR environment is at the animator's disposal. However, when XSAMPL3D descriptions are derived from VR interactions, they can accomodate many details of the demonstrated action, such as motion trajectiories,hand shapes and other hand-object relations during grasping. Such detail would be hard to specify with manual motion authoring techniques only. Through the inclusion of language features that allow the representation of all relevant aspects of demonstrated object manipulations, XSAMPL3D is a suitable action representation language for the imitation-based approach to character animation.

Knowledgeable Feedback via a Cast of Virtual Characters with Different Competences

DynaLearn (http://www.DynaLearn.eu) develops a cognitive artefact that engages learners in an active learning by modelling process to develop conceptual system knowledge. Learners create external representations using diagrams. The diagrams capture conceptual knowledge using the Garp3 Qualitative Reasoning (QR) formalism [2]. The expressions can be simulated, confronting learners with the logical consequences thereof. To further aid learners, DynaLearn employs a sequence of knowledge representations (Learning Spaces, LS), with increasing complexity in terms of the modelling ingredients a learner can use [1]. An online repository contains QR models created by experts/teachers and learners. The server runs semantic services [4] to generate feedback at the request of learners via the workbench. The feedback is communicated to the learner via a set of virtual characters, each having its own competence [3]. A specific feedback thus incorporates three aspects: content, character appearance, and a didactic setting (e.g. Quiz mode). In the interactive event we will demonstrate the latest achievements of the DynaLearn project. First, the 6 learning spaces for learners to work with. Second, the generation of feedback relevant to the individual needs of a learner using Semantic Web technology. Third, the verbalization of the feedback via different animated virtual characters, notably: Basic help, Critic, Recommender, Quizmaster & Teachable agen

Intelligent system for interaction with virtual characters based on volumetric sensors

Dissertação de Mestrado, Engenharia Elétrica e Eletrónica, Instituto Superior de Engenharia, Universidade do Algarve, 2015

A Framework for Human-like Behavior in an Immersive Virtual World

Just as readers feel immersed when the story line adheres to their experiences, users will more easily feel immersed in a virtual environment if the behavior of the characters in that environment adheres to their expectations, based on their lifelong observations in the real world. This paper introduces a framework that allows authors to establish natural, human-like behavior, physical interaction and emotional engagement of characters living in a virtual environment. Represented by realistic virtual characters, this framework allows people to feel immersed in an Internet based virtual world in which they can meet and share experiences in a natural way as they can meet and share experiences in real life. Rather than just being visualized in a 3D space, the virtual characters (autonomous agents as well as avatars representing users) in the immersive environment facilitate social interaction and multi-party collaboration, mixing virtual with real.

Security issues within virtual worlds such as second life

The advancement in Internet and bandwidth has resulted in a number of new applications to be developed. An area of advancement has been in the development of virtual worlds, where people can interact together via virtual characters. Virtual World systems have been so complex that virtual lives can be lived, including all aspect of life such as education, commerce, social activities etc. Not surprisingly, the problems that exist in the real world such as theft, fraud, vandalism and terrorism, also exist in the virtual worlds. The more developed these virtual worlds become the greater the breaches of security will be in the virtual as well as the real world.This paper explores and categorises several security issues within the Virtual World of Second Life. It contributes to practice and research by emphasising the importance of security awareness for businesses and the general public in Virtual Worlds.

Gaze behavior nonlinear dynamics assessed in virtual immersion as a diagnostic index of sexual deviancy: preliminary results

This paper presents preliminary results about the use of virtual characters, penile plethysmography and gaze behaviour dynamics to assess deviant sexual preferences. Pedophile patients’ responses are compared to those of non-deviant subjects while they were immersed with virtual characters depicting relevant sexual features.

Learning Data-Driven Models of Non-Verbal Behaviors for Building Rapport Using an Intelligent Virtual Agent

There is a growing societal need to address the increasing prevalence of behavioral health issues, such as obesity, alcohol or drug use, and general lack of treatment adherence for a variety of health problems. The statistics, worldwide and in the USA, are daunting. Excessive alcohol use is the third leading preventable cause of death in the United States (with 79,000 deaths annually), and is responsible for a wide range of health and social problems. On the positive side though, these behavioral health issues (and associated possible diseases) can often be prevented with relatively simple lifestyle changes, such as losing weight with a diet and/or physical exercise, or learning how to reduce alcohol consumption. Medicine has therefore started to move toward finding ways of preventively promoting wellness, rather than solely treating already established illness. Evidence-based patient-centered Brief Motivational Interviewing (BMI) interven- tions have been found particularly effective in helping people find intrinsic motivation to change problem behaviors after short counseling sessions, and to maintain healthy lifestyles over the long-term. Lack of locally available personnel well-trained in BMI, however, often limits access to successful interventions for people in need. To fill this accessibility gap, Computer-Based Interventions (CBIs) have started to emerge. Success of the CBIs, however, critically relies on insuring engagement and retention of CBI users so that they remain motivated to use these systems and come back to use them over the long term as necessary. Because of their text-only interfaces, current CBIs can therefore only express limited empathy and rapport, which are the most important factors of health interventions. Fortunately, in the last decade, computer science research has progressed in the design of simulated human characters with anthropomorphic communicative abilities. Virtual characters interact using humans’ innate communication modalities, such as facial expressions, body language, speech, and natural language understanding. By advancing research in Artificial Intelligence (AI), we can improve the ability of artificial agents to help us solve CBI problems. To facilitate successful communication and social interaction between artificial agents and human partners, it is essential that aspects of human social behavior, especially empathy and rapport, be considered when designing human-computer interfaces. Hence, the goal of the present dissertation is to provide a computational model of rapport to enhance an artificial agent’s social behavior, and to provide an experimental tool for the psychological theories shaping the model. Parts of this thesis were already published in [LYL+12, AYL12, AL13, ALYR13, LAYR13, YALR13, ALY14].

Learning data-driven models of non-verbal behaviors for building rapport using an intelligent virtual agent

There is a growing societal need to address the increasing prevalence of behavioral health issues, such as obesity, alcohol or drug use, and general lack of treatment adherence for a variety of health problems. The statistics, worldwide and in the USA, are daunting. Excessive alcohol use is the third leading preventable cause of death in the United States (with 79,000 deaths annually), and is responsible for a wide range of health and social problems. On the positive side though, these behavioral health issues (and associated possible diseases) can often be prevented with relatively simple lifestyle changes, such as losing weight with a diet and/or physical exercise, or learning how to reduce alcohol consumption. Medicine has therefore started to move toward finding ways of preventively promoting wellness, rather than solely treating already established illness.^ Evidence-based patient-centered Brief Motivational Interviewing (BMI) interventions have been found particularly effective in helping people find intrinsic motivation to change problem behaviors after short counseling sessions, and to maintain healthy lifestyles over the long-term. Lack of locally available personnel well-trained in BMI, however, often limits access to successful interventions for people in need. To fill this accessibility gap, Computer-Based Interventions (CBIs) have started to emerge. Success of the CBIs, however, critically relies on insuring engagement and retention of CBI users so that they remain motivated to use these systems and come back to use them over the long term as necessary.^ Because of their text-only interfaces, current CBIs can therefore only express limited empathy and rapport, which are the most important factors of health interventions. Fortunately, in the last decade, computer science research has progressed in the design of simulated human characters with anthropomorphic communicative abilities. Virtual characters interact using humans’ innate communication modalities, such as facial expressions, body language, speech, and natural language understanding. By advancing research in Artificial Intelligence (AI), we can improve the ability of artificial agents to help us solve CBI problems.^ To facilitate successful communication and social interaction between artificial agents and human partners, it is essential that aspects of human social behavior, especially empathy and rapport, be considered when designing human-computer interfaces. Hence, the goal of the present dissertation is to provide a computational model of rapport to enhance an artificial agent’s social behavior, and to provide an experimental tool for the psychological theories shaping the model. Parts of this thesis were already published in [LYL+12, AYL12, AL13, ALYR13, LAYR13, YALR13, ALY14].^

Avatars and the «Imitation Game» – can machines smile?

Considering Alan Turing’s challenge in «Computing Machinery and Intelligence» (1950) – can machines play the «imitation game»? – it is proposed that the requirements of the Turing test are already implicitly being used for checking the credibility of virtual characters and avatars. Like characters, Avatars aim to visually express emotions (the exterior signs of the existence of feeling) and its creators have to resort to emotion codes. Traditional arts have profusely contributed for this field and, together with the science of anatomy, shaped the grounds for current Facial Action Coding System (FACS) and their databases. However, FACS researchers have to improve their «instruction tables» so that the machines will be able, in a near future, to be programmed to carry out the operation of recognizing human expressions (face and body) and classify them adequately. For the moment, the reproductions have to resort to the copy of real life expressions, and the presente smile of avatars comes from mirroring their human users.

L'apport des personnages virtuels simulant différentes dispositions affectives à l'évaluation des intérêts sexuels

La pléthymographie pénienne est considérée comme la méthode la plus objective pour évaluer les intérêts sexuels d'hommes adultes. Par contre, un nombre grandissant de chercheurs déplorent le manque de correspondance qui existe entre les stimuli présentés dans ce type d'évaluation et la réalité. Il est proposé de tenter de remédier à cette lacune en utilisant des personnages virtuels générés par ordinateur et présentant une variété de dispositions affectives lors d'évaluations pléthysmographiques. Ces stimuli n'ont jamais été utilisés dans l'évaluation des intérêts sexuels auprès d’agresseurs sexuels d'enfants. Cette thèse est composée de deux articles qui visent à soutenir le recours à ce type de stimuli lors d'évaluations pléthysmographiques. Afin d'atteindre cet objectif, des hommes ayant eu ou non des contacts sexuels avec des enfants ont été recrutés dans le but de les comparer. Une première étude empirique est bipartite. Elle vise en premier lieu à déterminer auprès d'une population étudiante si les dispositions affectives simulées par les personnages virtuels sont identifiables. Elle cherche ensuite à déterminer la capacité des personnages virtuels à générer un profil d'excitation sexuelle propre à un groupe d'individus n'ayant pas de problématique sexuelle. La seconde étude expérimentale porte sur la comparaison des profils de réponses érectiles issus de la présentation des personnages virtuels et évalue leur capacité à discriminer les individus selon qu'ils possèdent ou non des antécédents en matière de délinquance sexuelle envers les enfants. Dans l'ensemble, les résultats soutiennent l'utilisation de ces stimuli lors d'évaluations pléthysmographiques. Ils démontrent que les personnages virtuels simulent les dispositions affectives prévues et qu'ils génèrent des profils d'excitation sexuelle et des indices de déviance permettant de discriminer entre les groupes à l'étude. Ce projet de recherche présente les avantages associés à la présentation des personnages virtuels simulant différentes dispositions affectives lors de l'évaluation des intérêts sexuels chez les agresseurs d'enfants et propose des avenues intéressantes en termes d'évaluation et de traitement auprès de cette population.

Sexual presence and intentional dynamics: deviant and non-deviant sexual self-regulation from the first person stance

Child molesters (n=13) and sexually non-deviant subjects (n=29) were immersed with virtual characters depicting relevant sexual features while their sexual arousal and gaze behaviour were assessed to characterize their sexual preferences and intentional dynamics. Sexual arousal was measured using circumferential penile plethysmography (PPG). Gaze behaviour dynamics was derived from average gaze radial angular deviation (GRAD) and GRAD coefficient of variation (GRADCV). Results show distinct sexual arousal profiles according to sexual preferences and point towards the existence of specific gaze behaviour dynamics guided by sexual intentions. Theoretical interpretations are based on the ecological psychology of J.J. Gibson and the integrated theory of sexual offending (Ward, 2009; Ward & Beech, 2006). Theoretical underpinnings coming from these approaches are advocated as being especially well suited to explain how virtual reality can help probing into child molesters’ phenomenology as lived from the first-person stance.

ARBOT: augmented reality system for teaching logic algorithmic

This article purposes the ARBot, a system that has as main objective the presentation of concepts of logic for students of elementary and secondary education. The system was developed using the technology known as Augmented Reality (AR), which allows complement the actual environment where the user is, by adding virtual objects. In this scenario the RA created from a virtual game interface is used, through which cognitive challenges are presented. To solve these challenges, users must set up three-dimensional virtual characters using visual language. As a result it follows that, in a playful way, concepts of algorithms and programming are assimilated by users. In addition, the system enables two users to interact in a cooperative game mode. In cooperative mode, the system focuses on collaborative learning, since it allows users to jointly solve the cognitive challenge presented by the system.

Interactive Augmentation of Live Images using a HDR Stereo Camera

Adding virtual objects to real environments plays an important role in todays computer graphics: Typical examples are virtual furniture in a real room and virtual characters in real movies. For a believable appearance, consistent lighting of the virtual objects is required. We present an augmented reality system that displays virtual objects with consistent illumination and shadows in the image of a simple webcam. We use two high dynamic range video cameras with fisheye lenses permanently recording the environment illumination. A sampling algorithm selects a few bright parts in one of the wide angle images and the corresponding points in the second camera image. The 3D position can then be calculated using epipolar geometry. Finally, the selected point lights are used in a multi pass algorithm to draw the virtual object with shadows. To validate our approach, we compare the appearance and shadows of the synthetic objects with real objects.