HapticHead - Augmenting Reality via Tactile Cues

Information overload is increasingly becoming a challenge in today's world. Humans have only a limited amount of attention to allocate between sensory channels and tend to miss or misjudge critical sensory information when multiple activities are going on at the same time. For example, people may miss the sound of an approaching car when walking across the street while looking at their smartphones. Some sensory channels may also be impaired due to congenital or acquired conditions. Among sensory channels, touch is often experienced as obtrusive, especially when it occurs unexpectedly. Since tactile actuators can simulate touch, targeted tactile stimuli can provide users of virtual reality and augmented reality environments with important information for navigation, guidance, alerts, and notifications. In this dissertation, a tactile user interface around the head is presented to relieve or replace a potentially impaired visual channel, called \emph{HapticHead}. It is a high-resolution, omnidirectional, vibrotactile display that presents general, 3D directional, and distance information through dynamic tactile patterns. The head is well suited for tactile feedback because it is sensitive to mechanical stimuli and provides a large spherical surface area that enables the display of precise 3D information and allows the user to intuitively rotate the head in the direction of a stimulus based on natural mapping. Basic research on tactile perception on the head and studies on various use cases of head-based tactile feedback are presented in this thesis. Several investigations and user studies have been conducted on (a) the funneling illusion and localization accuracy of tactile stimuli around the head, (b) the ability of people to discriminate between different tactile patterns on the head, (c) approaches to designing tactile patterns for complex arrays of actuators, (d) increasing the immersion and presence level of virtual reality applications, and (e) assisting people with visual impairments in guidance and micro-navigation. In summary, tactile feedback around the head was found to be highly valuable as an additional information channel in various application scenarios. Most notable is the navigation of visually impaired individuals through a micro-navigation obstacle course, which is an order of magnitude more accurate than the previous state-of-the-art, which used a tactile belt as a feedback modality. The HapticHead tactile user interface's ability to safely navigate people with visual impairments around obstacles and on stairs with a mean deviation from the optimal path of less than 6~cm may ultimately improve the quality of life for many people with visual impairments.Die Informationsüberlastung wird in der heutigen Welt zunehmend zu einer Herausforderung. Der Mensch hat nur eine begrenzte Menge an Aufmerksamkeit, die er zwischen den Sinneskanälen aufteilen kann, und neigt dazu, kritische Sinnesinformationen zu verpassen oder falsch einzuschätzen, wenn mehrere Aktivitäten gleichzeitig ablaufen. Zum Beispiel können Menschen das Geräusch eines herannahenden Autos überhören, wenn sie über die Straße gehen und dabei auf ihr Smartphone schauen. Einige Sinneskanäle können auch aufgrund von angeborenen oder erworbenen Erkrankungen beeinträchtigt sein. Unter den Sinneskanälen wird Berührung oft als aufdringlich empfunden, besonders wenn sie unerwartet auftritt. Da taktile Aktoren Berührungen simulieren können, können gezielte taktile Reize den Benutzern von Virtual- und Augmented Reality Anwendungen wichtige Informationen für die Navigation, Führung, Warnungen und Benachrichtigungen liefern. In dieser Dissertation wird eine taktile Benutzeroberfläche um den Kopf herum präsentiert, um einen möglicherweise beeinträchtigten visuellen Kanal zu entlasten oder zu ersetzen, genannt \emph{HapticHead}. Es handelt sich um ein hochauflösendes, omnidirektionales, vibrotaktiles Display, das allgemeine, 3D-Richtungs- und Entfernungsinformationen durch dynamische taktile Muster darstellt. Der Kopf eignet sich gut für taktiles Feedback, da er empfindlich auf mechanische Reize reagiert und eine große sphärische Oberfläche bietet, die die Darstellung präziser 3D-Informationen ermöglicht und es dem Benutzer erlaubt, den Kopf aufgrund der natürlichen Zuordnung intuitiv in die Richtung eines Reizes zu drehen. Grundlagenforschung zur taktilen Wahrnehmung am Kopf und Studien zu verschiedenen Anwendungsfällen von kopfbasiertem taktilem Feedback werden in dieser Arbeit vorgestellt. Mehrere Untersuchungen und Nutzerstudien wurden durchgeführt zu (a) der Funneling Illusion und der Lokalisierungsgenauigkeit von taktilen Reizen am Kopf, (b) der Fähigkeit von Menschen, zwischen verschiedenen taktilen Mustern am Kopf zu unterscheiden, (c) Ansätzen zur Gestaltung taktiler Muster für komplexe Arrays von Aktoren, (d) der Erhöhung des Immersions- und Präsenzgrades von Virtual-Reality-Anwendungen und (e) der Unterstützung von Menschen mit Sehbehinderungen bei der Führung und Mikronavigation. Zusammenfassend wurde festgestellt, dass taktiles Feedback um den Kopf herum als zusätzlicher Informationskanal in verschiedenen Anwendungsszenarien sehr wertvoll ist. Am interessantesten ist die Navigation von sehbehinderten Personen durch einen Mikronavigations-Hindernisparcours, welche um eine Größenordnung präziser ist als der bisherige Stand der Technik, der einen taktilen Gürtel als Feedback-Modalität verwendete. Die Fähigkeit der taktilen Benutzerschnittstelle HapticHead, Menschen mit Sehbehinderungen mit einer mittleren Abweichung vom optimalen Pfad von weniger als 6~cm sicher um Hindernisse und auf Treppen zu navigieren, kann letztendlich die Lebensqualität vieler Menschen mit Sehbehinderungen verbessern

Peripheral Notifications: Effects of Feature Combination and Task Interference

Visual notifications are integral to interactive computing systems. The design of visual notifications entails two main considerations: first, visual notifications should be noticeable, as they usually aim to attract a user`s attention to a location away from their main task; second, their noticeability has to be moderated to prevent user distraction and annoyance. Although notifications have been around for a long time on standard desktop environments, new computing environments such as large screens add new factors that have to be taken into account when designing notifications. With large displays, much of the content is in the user's visual periphery, where human capacity to notice visual effects is diminished. One design strategy for enhancing noticeability is to combine visual features, such as motion and colour. Yet little is known about how feature combinations affect noticeability across the visual field, or about how peripheral noticeability changes when a user is working on an attention-demanding task. We addressed these questions by conducting two studies. We conducted a laboratory study that tested people's ability to detect popout targets that used combinations of three visual variables. After determining that the noticeability of feature combinations were approximately equal to the better of the individual features, we designed an experiment to investigate peripheral noticeability and distraction when a user is focusing on a primary task. Our results suggest that there can be interference between the demands of primary tasks and the visual features in the notifications. Furthermore, primary task performance is adversely affected by motion effects in the peripheral notifications. Our studies contribute to a better understanding of how visual features operate when used as peripheral notifications. We provide new insights, both in terms of combining features, and interactions with primary tasks

Smart Assistive Technology for People with Visual Field Loss

Visual field loss results in the lack of ability to clearly see objects in the surrounding environment, which affects the ability to determine potential hazards. In visual field loss, parts of the visual field are impaired to varying degrees, while other parts may remain healthy. This defect can be debilitating, making daily life activities very stressful. Unlike blind people, people with visual field loss retain some functional vision. It would be beneficial to intelligently augment this vision by adding computer-generated information to increase the users' awareness of possible hazards by providing early notifications. This thesis introduces a smart hazard attention system to help visual field impaired people with their navigation using smart glasses and a real-time hazard classification system. This takes the form of a novel, customised, machine learning-based hazard classification system that can be integrated into wearable assistive technology such as smart glasses. The proposed solution provides early notifications based on (1) the visual status of the user and (2) the motion status of the detected object. The presented technology can detect multiple objects at the same time and classify them into different hazard types. The system design in this work consists of four modules: (1) a deep learning-based object detector to recognise static and moving objects in real-time, (2) a Kalman Filter-based multi-object tracker to track the detected objects over time to determine their motion model, (3) a Neural Network-based classifier to determine the level of danger for each hazard using its motion features extracted while the object is in the user's field of vision, and (4) a feedback generation module to translate the hazard level into a smart notification to increase user's cognitive perception using the healthy vision within the visual field. For qualitative system testing, normal and personalised defected vision models were implemented. The personalised defected vision model was created to synthesise the visual function for the people with visual field defects. Actual central and full-field test results were used to create a personalised model that is used in the feedback generation stage of this system, where the visual notifications are displayed in the user's healthy visual area. The proposed solution will enhance the quality of life for people suffering from visual field loss conditions. This non-intrusive, wearable hazard detection technology can provide obstacle avoidance solution, and prevent falls and collisions early with minimal information

A Smart Context-Aware Hazard Attention System to Help People with Peripheral Vision Loss

Peripheral vision loss results in the inability to detect objects in the peripheral visual field which affects the ability to evaluate and avoid potential hazards. A different number of assistive navigation systems have been developed to help people with vision impairments using wearable and portable devices. Most of these systems are designed to search for obstacles and provide safe navigation paths for visually impaired people without any prioritisation of the degree of danger for each hazard. This paper presents a new context-aware hybrid (indoor/outdoor) hazard classification assistive technology to help people with peripheral vision loss in their navigation using computer-enabled smart glasses equipped with a wide-angle camera. Our proposed system augments users’ existing healthy vision with suitable, meaningful and smart notifications to attract the user’s attention to possible obstructions or hazards in their peripheral field of view. A deep learning object detector is implemented to recognise static and moving objects in real time. After detecting the objects, a Kalman Filter multi-object tracker is used to track these objects over time to determine the motion model. For each tracked object, its motion model represents its way of moving around the user. Motion features are extracted while the object is still in the user’s field of vision. These features are then used to quantify the danger using five predefined hazard classes using a neural network-based classifier. The classification performance is tested on both publicly available and private datasets and the system shows promising results with up to 90% True Positive Rate (TPR) associated with as low as 7% False Positive Rate (FPR), 13% False Negative Rate (FNR) and an average testing Mean Square Error (MSE) of 8.8%. The provided hazard type is then translated into a smart notification to increase the user’s cognitive perception using the healthy vision within the visual field. A participant study was conducted with a group of patients with different visual field defects to explore their feedback about the proposed system and the notification generation stage. The real-world outdoor evaluation of human subjects is planned to be performed in our near future work

Leveraging eXtented Reality & Human-Computer Interaction for User Experi- ence in 360◦ Video

EXtended Reality systems have resurged as a medium for work and entertainment. While 360o video has been characterized as less immersive than computer-generated VR, its realism, ease of use and affordability mean it is in widespread commercial use. Based on the prevalence and potential of the 360o video format, this research is focused on improving and augmenting the user experience of watching 360o video. By leveraging knowledge from Extented Reality (XR) systems and Human-Computer Interaction (HCI), this research addresses two issues affecting user experience in 360o video: Attention Guidance and Visually Induced Motion Sickness (VIMS). This research work relies on the construction of multiple artifacts to answer the de- fined research questions: (1) IVRUX, a tool for analysis of immersive VR narrative expe- riences; (2) Cue Control, a tool for creation of spatial audio soundtracks for 360o video, as well as enabling the collection and analysis of captured metrics emerging from the user experience; and (3) VIMS mitigation pipeline, a linear sequence of modules (including optical flow and visual SLAM among others) that control parameters for visual modi- fications such as a restricted Field of View (FoV). These artifacts are accompanied by evaluation studies targeting the defined research questions. Through Cue Control, this research shows that non-diegetic music can be spatialized to act as orientation for users. A partial spatialization of music was deemed ineffective when used for orientation. Addi- tionally, our results also demonstrate that diegetic sounds are used for notification rather than orientation. Through VIMS mitigation pipeline, this research shows that dynamic restricted FoV is statistically significant in mitigating VIMS, while mantaining desired levels of Presence. Both Cue Control and the VIMS mitigation pipeline emerged from a Research through Design (RtD) approach, where the IVRUX artifact is the product of de- sign knowledge and gave direction to research. The research presented in this thesis is of interest to practitioners and researchers working on 360o video and helps delineate future directions in making 360o video a rich design space for interaction and narrative.Sistemas de Realidade EXtendida ressurgiram como um meio de comunicação para o tra- balho e entretenimento. Enquanto que o vídeo 360o tem sido caracterizado como sendo menos imersivo que a Realidade Virtual gerada por computador, o seu realismo, facili- dade de uso e acessibilidade significa que tem uso comercial generalizado. Baseado na prevalência e potencial do formato de vídeo 360o, esta pesquisa está focada em melhorar e aumentar a experiência de utilizador ao ver vídeos 360o. Impulsionado por conhecimento de sistemas de Realidade eXtendida (XR) e Interacção Humano-Computador (HCI), esta pesquisa aborda dois problemas que afetam a experiência de utilizador em vídeo 360o: Orientação de Atenção e Enjoo de Movimento Induzido Visualmente (VIMS). Este trabalho de pesquisa é apoiado na construção de múltiplos artefactos para res- ponder as perguntas de pesquisa definidas: (1) IVRUX, uma ferramenta para análise de experiências narrativas imersivas em VR; (2) Cue Control, uma ferramenta para a criação de bandas sonoras de áudio espacial, enquanto permite a recolha e análise de métricas capturadas emergentes da experiencia de utilizador; e (3) canal para a mitigação de VIMS, uma sequência linear de módulos (incluindo fluxo ótico e SLAM visual entre outros) que controla parâmetros para modificações visuais como o campo de visão restringido. Estes artefactos estão acompanhados por estudos de avaliação direcionados para às perguntas de pesquisa definidas. Através do Cue Control, esta pesquisa mostra que música não- diegética pode ser espacializada para servir como orientação para os utilizadores. Uma espacialização parcial da música foi considerada ineficaz quando usada para a orientação. Adicionalmente, os nossos resultados demonstram que sons diegéticos são usados para notificação em vez de orientação. Através do canal para a mitigação de VIMS, esta pesquisa mostra que o campo de visão restrito e dinâmico é estatisticamente significante ao mitigar VIMS, enquanto mantem níveis desejados de Presença. Ambos Cue Control e o canal para a mitigação de VIMS emergiram de uma abordagem de Pesquisa através do Design (RtD), onde o artefacto IVRUX é o produto de conhecimento de design e deu direcção à pesquisa. A pesquisa apresentada nesta tese é de interesse para profissionais e investigadores tra- balhando em vídeo 360o e ajuda a delinear futuras direções em tornar o vídeo 360o um espaço de design rico para a interação e narrativa

Enhanced Virtuality: Increasing the Usability and Productivity of Virtual Environments

Mit stetig steigender Bildschirmauflösung, genauerem Tracking und fallenden Preisen stehen Virtual Reality (VR) Systeme kurz davor sich erfolgreich am Markt zu etablieren. Verschiedene Werkzeuge helfen Entwicklern bei der Erstellung komplexer Interaktionen mit mehreren Benutzern innerhalb adaptiver virtueller Umgebungen. Allerdings entstehen mit der Verbreitung der VR-Systeme auch zusätzliche Herausforderungen: Diverse Eingabegeräte mit ungewohnten Formen und Tastenlayouts verhindern eine intuitive Interaktion. Darüber hinaus zwingt der eingeschränkte Funktionsumfang bestehender Software die Nutzer dazu, auf herkömmliche PC- oder Touch-basierte Systeme zurückzugreifen. Außerdem birgt die Zusammenarbeit mit anderen Anwendern am gleichen Standort Herausforderungen hinsichtlich der Kalibrierung unterschiedlicher Trackingsysteme und der Kollisionsvermeidung. Beim entfernten Zusammenarbeiten wird die Interaktion durch Latenzzeiten und Verbindungsverluste zusätzlich beeinflusst. Schließlich haben die Benutzer unterschiedliche Anforderungen an die Visualisierung von Inhalten, z.B. Größe, Ausrichtung, Farbe oder Kontrast, innerhalb der virtuellen Welten. Eine strikte Nachbildung von realen Umgebungen in VR verschenkt Potential und wird es nicht ermöglichen, die individuellen Bedürfnisse der Benutzer zu berücksichtigen. Um diese Probleme anzugehen, werden in der vorliegenden Arbeit Lösungen in den Bereichen Eingabe, Zusammenarbeit und Erweiterung von virtuellen Welten und Benutzern vorgestellt, die darauf abzielen, die Benutzerfreundlichkeit und Produktivität von VR zu erhöhen. Zunächst werden PC-basierte Hardware und Software in die virtuelle Welt übertragen, um die Vertrautheit und den Funktionsumfang bestehender Anwendungen in VR zu erhalten. Virtuelle Stellvertreter von physischen Geräten, z.B. Tastatur und Tablet, und ein VR-Modus für Anwendungen ermöglichen es dem Benutzer reale Fähigkeiten in die virtuelle Welt zu übertragen. Des Weiteren wird ein Algorithmus vorgestellt, der die Kalibrierung mehrerer ko-lokaler VR-Geräte mit hoher Genauigkeit und geringen Hardwareanforderungen und geringem Aufwand ermöglicht. Da VR-Headsets die reale Umgebung der Benutzer ausblenden, wird die Relevanz einer Ganzkörper-Avatar-Visualisierung für die Kollisionsvermeidung und das entfernte Zusammenarbeiten nachgewiesen. Darüber hinaus werden personalisierte räumliche oder zeitliche Modifikationen vorgestellt, die es erlauben, die Benutzerfreundlichkeit, Arbeitsleistung und soziale Präsenz von Benutzern zu erhöhen. Diskrepanzen zwischen den virtuellen Welten, die durch persönliche Anpassungen entstehen, werden durch Methoden der Avatar-Umlenkung (engl. redirection) kompensiert. Abschließend werden einige der Methoden und Erkenntnisse in eine beispielhafte Anwendung integriert, um deren praktische Anwendbarkeit zu verdeutlichen. Die vorliegende Arbeit zeigt, dass virtuelle Umgebungen auf realen Fähigkeiten und Erfahrungen aufbauen können, um eine vertraute und einfache Interaktion und Zusammenarbeit von Benutzern zu gewährleisten. Darüber hinaus ermöglichen individuelle Erweiterungen des virtuellen Inhalts und der Avatare Einschränkungen der realen Welt zu überwinden und das Erlebnis von VR-Umgebungen zu steigern