VRpursuits: Interaction in Virtual Reality Using Smooth Pursuit Eye Movements

Gaze-based interaction using smooth pursuit eye movements (Pursuits) is attractive given that it is intuitive and overcomes the Midas touch problem. At the same time, eye tracking is becoming increasingly popular for VR applications. While Pursuits was shown to be effective in several interaction contexts, it was never explored in-depth for VR before. In a user study (N=26), we investigated how parameters that are specific to VR settings influence the performance of Pursuits. For example, we found that Pursuits is robust against different sizes of virtual 3D targets. However performance improves when the trajectory size (e.g., radius) is larger, particularly if the user is walking while interacting. While walking, selecting moving targets via Pursuits is generally feasible albeit less accurate than when stationary. Finally, we discuss the implications of these findings and the potential of smooth pursuits for interaction in VR by demonstrating two sample use cases: 1) gaze-based authentication in VR, and 2) a space meteors shooting game

When the Elephant Trumps": A Comparative Study on Spatial Audio for Orientation in 360◦ Videos

Orientation is an emerging issue in cinematic Virtual Reality (VR), as viewers may fail in locating points of interest. Recent strategies to tackle this research problem have investigated the role of cues, specifically diegetic sound effects. In this paper, we examine the use of sound spatialization for orien tation purposes, namely by studying different spatialization conditions ("none", "partial", and "full" spatial manipulation) of multitrack soundtracks. We performed a between-subject mixed-methods study with 36 participants, aided by Cue Control, a tool we developed for dynamic spatial sound edit ing and data collection/analysis. Based on existing literature on orientation cues in 360◦ and theories on human listening, we discuss situations in which the spatialization was more ef fective (namely, "full" spatial manipulation both when using only music and when combining music and diegetic effects), and how this can be used by creators of 360◦ videos.info:eu-repo/semantics/publishedVersio

Visual complexity in human-machine interaction = Visuelle Komplexität in der Mensch-Maschine Interaktion

Visuelle Komplexität wird oft als der Grad an Detail oder Verworrenheit in einem Bild definiert (Snodgrass & Vanderwart, 1980). Diese hat Einfluss auf viele Bereiche des menschlichen Lebens, darunter auch solche, die die Interaktion mit Technologie invol-vieren. So wurden Effekte visueller Komplexität etwa im Straßenverkehr (Edquist et al., 2012; Mace & Pollack, 1983) oder bei der Interaktion mit Software (Alemerien & Magel, 2014) oder Webseiten (Deng & Poole, 2010; Tuch et al., 2011) nachgewie-sen. Obwohl die Erforschung visueller Komplexität bereits bis auf die Gestaltpsycho-logen zurückgeht, welche etwa mit dem Gestaltprinzip der Prägnanz die Bedeutung von Simplizität und Komplexität im Wahrnehmungsprozess verankerten (Koffka, 1935; Wertheimer, 1923), sind weder die Einflussfaktoren visueller Komplexität, noch die Zusammenhänge mit Blickbewegungen oder mentaler Beanspruchung bisher ab-schließend erforscht. Diese Punkte adressiert die vorliegende Arbeit mithilfe von vier empirischen Forschungsarbeiten. In Studie 1 wird anhand der Komplexität von Videos in Leitwarten sowie der Effekte auf subjektive, physiologische und Leistungsparameter mentaler Beanspruchung die Bedeutung des Konstruktes im Bereich der Mensch-Maschine Interaktion untersucht. Studie 2 betrachtet die dimensionale Struktur und die Bedeutung verschiedener Ein-flussfaktoren visueller Komplexität genauer, wobei unterschiedliches Stimulusmaterial genutzt wird. In Studie 3 werden mithilfe eines experimentellen Ansatzes die Auswir-kungen von Einflussfaktoren visueller Komplexität auf subjektive Bewertungen sowie eine Auswahl okularer Parameter untersucht. Als Stimuli dienen dabei einfache, schwarz-weiße Formenmuster. Zudem werden verschiedene computationale und oku-lare Parameter genutzt, um anhand dieser Komplexitätsbewertungen vorherzusagen. Dieser Ansatz wird in Studie 4 auf Screenshots von Webseiten übertragen, um die Aussagekraft in einem anwendungsnahen Bereich zu untersuchen. Neben vorangegangenen Forschungsarbeiten legen insbesondere die gefundenen Zusammenhänge mit mentaler Beanspruchung nahe, dass visuelle Komplexität ein relevantes Konstrukt im Bereich der Mensch-Maschine Interaktion darstellt. Dabei haben insbesondere quantitative und strukturelle, aber potentiell auch weitere Aspekte Einfluss auf die Bewertung visueller Komplexität sowie auf das Blickverhalten der Be-trachter. Die gewonnenen Ergebnisse erlauben darüber hinaus Rückschlüsse auf die Zusammenhänge mit computationalen Maßen, welche in Kombination mit okularen Parametern gut für die Vorhersage von Komplexitätsbewertungen geeignet sind. Die Erkenntnisse aus den durchgeführten Studien werden im Kontext vorheriger For-schungsarbeiten diskutiert. Daraus wird ein integratives Forschungsmodell visueller Komplexität in der Mensch-Maschine-Interaktion abgeleitet

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

Coordinated Eye and Head Movements for Gaze Interaction in 3D Environments

Gaze is attractive for interaction, as we naturally look at objects we are interested in. As a result, gaze has received significant attention within human-computer interaction as an input modality. However, gaze has been limited to only eye movements in situations where head movements are not expected to be used or as head movements in an approximation of gaze when an eye tracker is unavailable. From these observations arise an opportunity and a challenge: we propose to consider gaze as multi-modal in line with psychology and neuroscience research to more accurately represent user movements. The natural coordination of eye and head movements could then enable the development of novel interaction techniques to further the possibilities of gaze as an input modality. However, knowledge of the eye and head coordination in 3D environments and its usage for interaction design is limited. This thesis explores eye and head coordination and their potential for interaction in 3D environments by developing interaction techniques that aim to tackle established gaze-interaction issues. We study fundamental eye, head, and body movements in virtual reality during gaze shifts. From the study results, we design interaction techniques and applications that avoid the Midas touch issue, allow expressive gaze- based interaction, and handle eye tracking accuracy issues. We ground the evaluation of our interaction techniques through empirical studies. From the techniques and study results, we define three design principles for coordinated eye and head interaction from these works that distinguish between eye- only and head-supported gaze shifts, eye-head alignment as input, and distinguishing head movements for gestures and head movements that naturally occur to support gaze. We showcase new directions for gaze-based interaction and present a new way to think about gaze by taking a more comprehensive approach to gaze interaction and showing that there is more to gaze than just the eyes

La città, il viaggio, il turismo: Percezione, produzione e trasformazione

[English]:The city as a destination of the journey in his long evolution throughout history: a basic human need, an event aimed at knowledge, to education, to business and trade, military and religious conquests, but also related to redundancies for the achievement of mere physical or spiritual salvation. In the frame of one of the world's most celebrated historical city, the cradle of Greek antiquity, myth and beauty, travel timeless destination for culture and leisure, and today, more than ever, strongly tending to the conservation and development of their own identity, this collection of essays aims to provide, in the tradition of AISU studies, a further opportunity for reflection and exchange between the various disciplines related to urban history./ [Italiano]:La città come meta del viaggio nella sua lunga evoluzione nel corso della storia: un bisogno primario dell'uomo, un evento finalizzato alla conoscenza, all'istruzione, agli affari e agli scambi commerciali, alle conquiste militari o religiose, ma anche legato agli esodi per il conseguimento della mera salvezza fisica o spirituale. Nella cornice di una delle città storiche più celebrate al mondo, culla dell'antichità greca, del mito e della bellezza, meta intramontabile di viaggi di cultura e di piacere, e oggi, più che mai, fortemente protesa alla conservazione e alla valorizzazione della propria identità, questa raccolta di saggi intende offrire, nel solco della tradizione di studi dell'AISU, un'ulteriore occasione di riflessione e di confronto tra i più svariati ambiti disciplinari attinenti alla storia urbana