3D Multimodal Interaction with Physically-based Virtual Environments

The virtual has become a huge field of exploration for researchers: it could assist the surgeon, help the prototyping of industrial objects, simulate natural phenomena, be a fantastic time machine or entertain users through games or movies. Far beyond the only visual rendering of the virtual environment, the Virtual Reality aims at -literally- immersing the user in the virtual world. VR technologies simulate digital environments with which users can interact and, as a result, perceive through different modalities the effects of their actions in real time. The challenges are huge: the user's motions need to be perceived and to have an immediate impact on the virtual world by modifying the objects in real-time. In addition, the targeted immersion of the user is not only visual: auditory or haptic feedback needs to be taken into account, merging all the sensory modalities of the user into a multimodal answer. The global objective of my research activities is to improve 3D interaction with complex virtual environments by proposing novel approaches for physically-based and multimodal interaction. I have laid the foundations of my work on designing the interactions with complex virtual worlds, referring to a higher demand in the characteristics of the virtual environments. My research could be described within three main research axes inherent to the 3D interaction loop: (1) the physically-based modeling of the virtual world to take into account the complexity of the virtual object behavior, their topology modifications as well as their interactions, (2) the multimodal feedback for combining the sensory modalities into a global answer from the virtual world to the user and (3) the design of body-based 3D interaction techniques and devices for establishing the interfaces between the user and the virtual world. All these contributions could be gathered in a general framework within the 3D interaction loop. By improving all the components of this framework, I aim at proposing approaches that could be used in future virtual reality applications but also more generally in other areas such as medical simulation, gesture training, robotics, virtual prototyping for the industry or web contents.Le virtuel est devenu un vaste champ d'exploration pour la recherche et offre de nos jours de nombreuses possibilités : assister le chirurgien, réaliser des prototypes de pièces industrielles, simuler des phénomènes naturels, remonter dans le temps ou proposer des applications ludiques aux utilisateurs au travers de jeux ou de films. Bien plus que le rendu purement visuel d'environnement virtuel, la réalité virtuelle aspire à -littéralement- immerger l'utilisateur dans le monde virtuel. L'utilisateur peut ainsi interagir avec le contenu numérique et percevoir les effets de ses actions au travers de différents retours sensoriels. Permettre une véritable immersion de l'utilisateur dans des environnements virtuels de plus en plus complexes confronte la recherche en réalité virtuelle à des défis importants: les gestes de l'utilisateur doivent être capturés puis directement transmis au monde virtuel afin de le modifier en temps-réel. Les retours sensoriels ne sont pas uniquement visuels mais doivent être combinés avec les retours auditifs ou haptiques dans une réponse globale multimodale. L'objectif principal de mes activités de recherche consiste à améliorer l'interaction 3D avec des environnements virtuels complexes en proposant de nouvelles approches utilisant la simulation physique et exploitant au mieux les différentes modalités sensorielles. Dans mes travaux, je m'intéresse tout particulièrement à concevoir des interactions avec des mondes virtuels complexes. Mon approche peut être décrite au travers de trois axes principaux de recherche: (1) la modélisation dans les mondes virtuels d'environnements physiques plausibles où les objets réagissent de manière naturelle, même lorsque leur topologie est modifiée ou lorsqu'ils sont en interaction avec d'autres objets, (2) la mise en place de retours sensoriels multimodaux vers l'utilisateur intégrant des composantes visuelles, haptiques et/ou sonores, (3) la prise en compte de l'interaction physique de l'utilisateur avec le monde virtuel dans toute sa richesse : mouvements de la tête, des deux mains, des doigts, des jambes, voire de tout le corps, en concevant de nouveaux dispositifs ou de nouvelles techniques d'interactions 3D. Les différentes contributions que j'ai proposées dans chacun de ces trois axes peuvent être regroupées au sein d'un cadre plus général englobant toute la boucle d'interaction 3D avec les environnements virtuels. Elles ouvrent des perspectives pour de futures applications en réalité virtuelle mais également plus généralement dans d'autres domaines tels que la simulation médicale, l'apprentissage de gestes, la robotique, le prototypage virtuel pour l'industrie ou bien les contenus web

Understanding Hand Interactions and Mid-Air Haptic Responses within Virtual Reality and Beyond.

Hand tracking has long been seen as a futuristic interaction, firmly situated into the realms of sci-fi. Recent developments and technological advancements have brought that dream into reality, allowing for real-time interactions by naturally moving and positioning your hand. While these developments have enabled numerous research projects, it is only recently that businesses and devices are truly starting to implement and integrate the technology into their different sectors. Numerous devices are shifting towards a fully self- contained ecosystem, where the removal of controllers could significantly help in reducing barriers to entry. Prior studies have focused on the effects or possible areas for implementation of hand tracking, but rarely focus on the direct comparisons of technologies, nor do they attempt to reproduce lost capabilities. With this prevailing background, the work presented in this thesis aims to understand the benefits and negatives of hand tracking when treated as the primary interaction method within virtual reality (VR) environments. Coupled with this, the implementation and usage of novel mid-air ultrasound-based haptics attempt to reintroduce feedback that would have been achieved through conventional controller interactions. Two unique user studies were undertaken, testing core underlying interactions within VR that represent common instances found throughout simulations. The first study focuses on the interactions presented within 3D VR user interfaces, with a core topic of buttons. While the second study directly compares input and haptic modalities within two different fine motor skill tasks. These studies are coupled with the development and implementation of a real-time user study recording toolkit, allowing for significantly heightened user analysis and visual evaluation of interactions. Results from these studies and developments make valuable contributions to the research and business knowledge of hand tracking interactions, as well as providing a uniquely valuable open-source toolkit for other researchers to use. This thesis covers work undertaken at Ultraleap over varying projects between 2018 and 2021

Musical Haptics

Haptic Musical Instruments; Haptic Psychophysics; Interface Design and Evaluation; User Experience; Musical Performanc

Virtual Reality Games for Motor Rehabilitation

This paper presents a fuzzy logic based method to track user satisfaction without the need for devices to monitor users physiological conditions. User satisfaction is the key to any product’s acceptance; computer applications and video games provide a unique opportunity to provide a tailored environment for each user to better suit their needs. We have implemented a non-adaptive fuzzy logic model of emotion, based on the emotional component of the Fuzzy Logic Adaptive Model of Emotion (FLAME) proposed by El-Nasr, to estimate player emotion in UnrealTournament 2004. In this paper we describe the implementation of this system and present the results of one of several play tests. Our research contradicts the current literature that suggests physiological measurements are needed. We show that it is possible to use a software only method to estimate user emotion

Musical Haptics

Haptic Musical Instruments; Haptic Psychophysics; Interface Design and Evaluation; User Experience; Musical Performanc