Investigating Embodied Interaction in Near-Field Perception-Action Re-Calibration on Performance in Immersive Virtual Environments

Immersive Virtual Environments (IVEs) are becoming more accessible and more widely utilized for training. Previous research has shown that the matching of visual and proprioceptive information is important for calibration. Many state-of-the art Virtual Reality (VR) systems, commonly known as Immersive Virtual Environments (IVE), are created for training users in tasks that require accurate manual dexterity. Unfortunately, these systems can suffer from technical limitations that may force de-coupling of visual and proprioceptive information due to interference, latency, and tracking error. It has also been suggested that closed-loop feedback of travel and locomotion in an IVE can overcome compression of visually perceived depth in medium field distances in the virtual world [33, 47]. Very few experiments have examined the carryover effects of multi-sensory feedback in IVEs during manual dexterous 3D user interaction in overcoming distortions in near-field or interaction space depth perception, and the relative importance of visual and proprioceptive information in calibrating users\u27 distance judgments. In the first part of this work, we examined the recalibration of movements when the visually reached distance is scaled differently than the physically reached distance. We present an empirical evaluation of how visually distorted movements affects users\u27 reach to near field targets in an IVE. In a between subjects design, participants provided manual reaching distance estimates during three sessions; a baseline measure without feedback (open-loop distance estimation), a calibration session with visual and proprioceptive feedback (closed-loop distance estimation), and a post-interaction session without feedback (open-loop distance estimation). Subjects were randomly assigned to one of three visual feedbacks in the closed-loop condition during which they reached to target while holding a tracked stylus: i) Minus condition (-20% gain condition) in which the visual stylus appeared at 80\% of the distance of the physical stylus, ii) Neutral condition (0% or no gain condition) in which the visual stylus was co-located with the physical stylus, and iii) Plus condition (+20% gain condition) in which the visual stylus appeared at 120% of the distance of the physical stylus. In all the conditions, there is evidence of visuo-motor calibration in that users\u27 accuracy in physically reaching to the target locations improved over trials. Scaled visual feedback was shown to calibrate distance judgments within an IVE, with estimates being farthest in the post-interaction session after calibrating to visual information appearing nearer (Minus condition), and nearest after calibrating to visual information appearing further (Plus condition). The same pattern was observed during closed-loop physical reach responses, participants generally tended to physically reach farther in Minus condition and closer in Plus condition to the perceived location of the targets, as compared to Neutral condition in which participants\u27 physical reach was more accurate to the perceived location of the target. We then characterized the properties of human reach motion in the presence or absence of visuo-haptic feedback in real and IVEs within a participant\u27s maximum arm reach. Our goal is to understand how physical reaching actions to the perceived location of targets in the presence or absence of visuo-haptic feedback are different between real and virtual viewing conditions. Typically, participants reach to the perceived location of objects in the 3D environment to perform selection and manipulation actions during 3D interaction in applications such as virtual assembly or rehabilitation. In these tasks, participants typically have distorted perceptual information in the IVE as compared to the real world, in part due to technological limitations such as minimal visual field of view, resolution, latency and jitter. In an empirical evaluation, we asked the following questions; i) how do the perceptual differences between virtual and real world affect our ability to accurately reach to the locations of 3D objects, and ii) how do the motor responses of participants differ between the presence or absence of visual and haptic feedback? We examined factors such as velocity and distance of physical reaching behavior between the real world and IVE, both in the presence or absence of visuo-haptic information. The results suggest that physical reach responses vary systematically between real and virtual environments especially in situations involving presence or absence of visuo-haptic feedback. The implications of our study provide a methodological framework for the analysis of reaching motions for selection and manipulation with novel 3D interaction metaphors and to successfully characterize visuo-haptic versus non-visuo-haptic physical reaches in virtual and real world situations. While research has demonstrated that self-avatars can enhance ones\u27 sense of presence and improve distance perception, the effects of self-avatar fidelity on near field distance estimations has yet to be investigated. Thus, we investigated the effect of visual fidelity of the self-avatar in enhancing the user\u27s depth judgments, reach boundary perception and properties of physical reach motion. Previous research has demonstrated that self-avatar representation of the user enhances the sense of presence [37] and even a static notion of an avatar can improve distance estimation in far distances [59, 48]. In this study, performance with a virtual avatar was also compared to real-world performance. Three levels of fidelity were tested; 1) an immersive self-avatar with realistic limbs, 2) a low-fidelity self-avatar showing only joint locations, and 3) end-effector only. There were four primary hypotheses; First, we hypothesize that just the existence of self-avatar or end-effector position would calibrate users\u27 interaction space depth perception in an IVE. Therefore, participants\u27 distance judgments would be improved after the calibration phase regardless of self-avatars\u27 visual fidelity. Second, the magnitude of the changes from pre-test to post-test would be significantly different based on the visual details of the self-avatar presented to the participants (self-avatar vs low-fidelity self-avatar and end-effector). Third, we predict distance estimation accuracy would be the highest in immersive self-avatar condition and the lowest in end-effector condition. Forth, we predict that the properties of physical reach responses vary systematically between different visual fidelity conditions. The results suggest that reach estimations become more accurate as the visual fidelity of the avatar increases, with accuracy for high fidelity avatars approaching real-world performance as compared to low-fidelity and end-effector conditions. There was also an effect of the phase where the reach estimate became more accurate after receiving feedback in calibration phase. Overall, in all conditions reach estimations became more accurate after receiving feedback during a calibration phase. Lastly, we examined factors such as path length, time to complete the task, average velocity and acceleration of physical reach motion and compared all the IVEs conditions with real-world. The results suggest that physical reach responses vary systematically between the VR viewing conditions and real-world

Exploring a Cognitive Basis for Learning Spatial Relationships with Augmented Reality

Augmented reality (AR) is an emergent class of interface that presents compelling possibilities for advancing spatial visualization. We offer a brief overview of AR technology and current research with in the educational realm. AR interfaces appear to provide a unique combination of visual display properties, modes of user manipulation, and interaction with spatial information. Drawing upon aspects of proprioception and sensorimotor function, we discuss how AR may have a unique and powerful link to spatial knowledge acquisition through visuo-motor involvement in the processing of information. We identify key properties of AR interfaces and how they differ from conventional visualization interfaces, followed by a discussion of theoretical perspectives that make a case for learning spatial relationships using first person manipulative AR.Recent research provides evidence that this form of AR holds cognitive advantages for learning when compared with traditional desktop 2D interfaces. We review the visual-physical connections to learning using first person manipulative AR within educational contexts. We then provide some suggestions for building future research in this area and explore its significance in the realm of spatial knowledge acquisition

Examining the Effects of Altered Avatars on Perception-Action in Virtual Reality

In virtual reality avatars are animated graphical representation of a person embedded in a virtual environment. Previous research has illustrated the benefits of having an avatar when perceiving aspects of virtual reality. We studied the effect that a non-faithful, or altered, avatar had on the perception of one\u27s action capabilities in VR. In Experiment 1, one group of participants acted with a normal, or faithful, avatar and the other group of participants used an avatar with an extended arm, all in virtual reality. In Experiment 2, the same methodology and procedure was used as in Experiment 1, except only the calibration phase occurred in VR, while the remaining reaches were completed in the real world. All participants performed reaches to various distances. The results of these studies show that calibration to altered dimensions of avatars is possible after receiving feedback while acting with the altered avatar. Further, calibration occurred more quickly when feedback was initially used to transition from a normal avatar to an altered avatar than when later transitioning from the altered avatar arm back to the normal avatar arm without feedback. The implications of these findings for training in virtual reality simulations and transfer back to the real world are also discussed

Advancing proxy-based haptic feedback in virtual reality

This thesis advances haptic feedback for Virtual Reality (VR). Our work is guided by Sutherland's 1965 vision of the ultimate display, which calls for VR systems to control the existence of matter. To push towards this vision, we build upon proxy-based haptic feedback, a technique characterized by the use of passive tangible props. The goal of this thesis is to tackle the central drawback of this approach, namely, its inflexibility, which yet hinders it to fulfill the vision of the ultimate display. Guided by four research questions, we first showcase the applicability of proxy-based VR haptics by employing the technique for data exploration. We then extend the VR system's control over users' haptic impressions in three steps. First, we contribute the class of Dynamic Passive Haptic Feedback (DPHF) alongside two novel concepts for conveying kinesthetic properties, like virtual weight and shape, through weight-shifting and drag-changing proxies. Conceptually orthogonal to this, we study how visual-haptic illusions can be leveraged to unnoticeably redirect the user's hand when reaching towards props. Here, we contribute a novel perception-inspired algorithm for Body Warping-based Hand Redirection (HR), an open-source framework for HR, and psychophysical insights. The thesis concludes by proving that the combination of DPHF and HR can outperform the individual techniques in terms of the achievable flexibility of the proxy-based haptic feedback.Diese Arbeit widmet sich haptischem Feedback für Virtual Reality (VR) und ist inspiriert von Sutherlands Vision des ultimativen Displays, welche VR-Systemen die Fähigkeit zuschreibt, Materie kontrollieren zu können. Um dieser Vision näher zu kommen, baut die Arbeit auf dem Konzept proxy-basierter Haptik auf, bei der haptische Eindrücke durch anfassbare Requisiten vermittelt werden. Ziel ist es, diesem Ansatz die für die Realisierung eines ultimativen Displays nötige Flexibilität zu verleihen. Dazu bearbeiten wir vier Forschungsfragen und zeigen zunächst die Anwendbarkeit proxy-basierter Haptik durch den Einsatz der Technik zur Datenexploration. Anschließend untersuchen wir in drei Schritten, wie VR-Systeme mehr Kontrolle über haptische Eindrücke von Nutzern erhalten können. Hierzu stellen wir Dynamic Passive Haptic Feedback (DPHF) vor, sowie zwei Verfahren, die kinästhetische Eindrücke wie virtuelles Gewicht und Form durch Gewichtsverlagerung und Veränderung des Luftwiderstandes von Requisiten vermitteln. Zusätzlich untersuchen wir, wie visuell-haptische Illusionen die Hand des Nutzers beim Greifen nach Requisiten unbemerkt umlenken können. Dabei stellen wir einen neuen Algorithmus zur Body Warping-based Hand Redirection (HR), ein Open-Source-Framework, sowie psychophysische Erkenntnisse vor. Abschließend zeigen wir, dass die Kombination von DPHF und HR proxy-basierte Haptik noch flexibler machen kann, als es die einzelnen Techniken alleine können

All Hands on Deck: Choosing Virtual End Effector Representations to Improve Near Field Object Manipulation Interactions in Extended Reality

Extended reality, or XR , is the adopted umbrella term that is heavily gaining traction to collectively describe Virtual reality (VR), Augmented reality (AR), and Mixed reality (MR) technologies. Together, these technologies extend the reality that we experience either by creating a fully immersive experience like in VR or by blending in the virtual and real worlds like in AR and MR. The sustained success of XR in the workplace largely hinges on its ability to facilitate efficient user interactions. Similar to interacting with objects in the real world, users in XR typically interact with virtual integrants like objects, menus, windows, and information that convolve together to form the overall experience. Most of these interactions involve near-field object manipulation for which users are generally provisioned with visual representations of themselves also called self-avatars. Representations that involve only the distal entity are called end-effector representations and they shape how users perceive XR experiences. Through a series of investigations, this dissertation evaluates the effects of virtual end effector representations on near-field object retrieval interactions in XR settings. Through studies conducted in virtual, augmented, and mixed reality, implications about the virtual representation of end-effectors are discussed, and inferences are made for the future of near-field interaction in XR to draw upon from. This body of research aids technologists and designers by providing them with details that help in appropriately tailoring the right end effector representation to improve near-field interactions, thereby collectively establishing knowledge that epitomizes the future of interactions in XR

Presence 2005: the eighth annual international workshop on presence, 21-23 September, 2005 University College London (Conference proceedings)

OVERVIEW (taken from the CALL FOR PAPERS) Academics and practitioners with an interest in the concept of (tele)presence are invited to submit their work for presentation at PRESENCE 2005 at University College London in London, England, September 21-23, 2005. The eighth in a series of highly successful international workshops, PRESENCE 2005 will provide an open discussion forum to share ideas regarding concepts and theories, measurement techniques, technology, and applications related to presence, the psychological state or subjective perception in which a person fails to accurately and completely acknowledge the role of technology in an experience, including the sense of 'being there' experienced by users of advanced media such as virtual reality. The concept of presence in virtual environments has been around for at least 15 years, and the earlier idea of telepresence at least since Minsky's seminal paper in 1980. Recently there has been a burst of funded research activity in this area for the first time with the European FET Presence Research initiative. What do we really know about presence and its determinants? How can presence be successfully delivered with today's technology? This conference invites papers that are based on empirical results from studies of presence and related issues and/or which contribute to the technology for the delivery of presence. Papers that make substantial advances in theoretical understanding of presence are also welcome. The interest is not solely in virtual environments but in mixed reality environments. Submissions will be reviewed more rigorously than in previous conferences. High quality papers are therefore sought which make substantial contributions to the field. Approximately 20 papers will be selected for two successive special issues for the journal Presence: Teleoperators and Virtual Environments. PRESENCE 2005 takes place in London and is hosted by University College London. The conference is organized by ISPR, the International Society for Presence Research and is supported by the European Commission's FET Presence Research Initiative through the Presencia and IST OMNIPRES projects and by University College London

Novel supports to the assessment of cognitive functions through the combined use of technologies and subjective and objective measurements

Tesis por compendio[ES] Las funciones cognitivas incluyen todos los procesos a través de los cuales un individuo percibe, registra, mantiene, manipula, usa y expresa información que está involucrada en cualquier actividad cotidiana. Las principales herramientas estandarizadas se pueden dividir en tres grupos principales: escalas cortas de pruebas de seguimiento cognitivo: cuestionarios, baterías neuropsicológicas generales y pruebas específicas. Estas herramientas están bien validadas y son confiables, pero, en la última década, varias investigaciones han demostrado que algunos pacientes pueden realizar bien estas pruebas neuropsicológicas, incluso cuando tienen dificultades significativas para adaptar sus comportamientos a las actividades de la vida diaria. De acuerdo con esto, más recientemente, un nuevo enfoque ha aumentado sustancialmente, lo que podría proporcionar una mayor validez ecológica en la evaluación de las capacidades cognitivas funcionales que el enfoque estandarizado: el uso de sistemas tecnológicos avanzados para la evaluación neuropsicológica (STAEN). STAEN se refiere a un conjunto de dispositivos y aplicaciones de software tales como pruebas computarizadas, juegos divertidos e interactivos de fantasía (JS) y / o sistemas de realidad virtual simulada (RV) y / o aumentada (RA) que van más allá de las pruebas de evaluación tradicionales y que Brindar la posibilidad de entregar estímulos controlados y dinámicos, en entornos ecológicamente válidos y seguros. Partiendo de estas premisas, el objetivo principal de la tesis era diseñar, desarrollar y validar un SG 2D no inmersivo versus un JS 3D inmersivo y una actividad de la vida diaria en un entorno 3D RV inmersivo versus un RA para la evaluación de funciones cognitivas, comparando la eficacia y efectividad de ellos. El primer estudio 2D incluyó 354 sujetos sanos y se encontraron correlaciones entre el juego y los métodos tradicionales, lo que sugiere que el juego podría ser una herramienta válida para evaluar las funciones cognitivas en adultos. El segundo estudio, comparó la versión 2D versus una versión 3D STAEN, involucró a 94 sujetos sanos y mostró que la versión 3D fue capaz de generar tiempos más bajos y respuestas correctas más altas que la 2D, lo que sugiere evidencia inicial de la eficacia de un sistema más inmersivo en comparación con un sistema no-inmersivo. Aunque este resultado destaca una posible limitación en el uso de diferentes sistemas tecnológicos debido a las diferencias en los dos métodos de interacción (el sistema 2D aplicó el mouse y el teclado; los controladores de dos manos virtuales 3D) y el registro de datos de latencia de hardware y software. Con respecto a la variabilidad individual en edad, género y educación, los hallazgos mostraron consistencia con la literatura de referencia. Específicamente, los más jóvenes mostraron un mayor rendimiento que los mayores; niveles educativos más altos reflejados en una mejor puntuación y sobre género, los resultados mostraron un panorama más compuesto. Además, para mejorar la validez ecológica de la evaluación, el último estudio de esta tesis comparó el rendimiento conductual y las respuestas fisiológicas, durante una tarea de cocina ecológica, entre un sistema virtual y un sistema aumentado en 50 sujetos sanos. La tarea de cocinar consistió en 4 niveles que aumentaron en dificultad. A medida que el nivel aumentó, aparecieron actividades adicionales. Los resultados de comportamiento mostraron que los tiempos son siempre más bajos en realidad virtual que en RA, aumentando constantemente de acuerdo con la dificultad de las tareas. Con respecto a las respuestas fisiológicas, los hallazgos mostraron que la condición RA produjo más excitación y activación individual que la realidad virtual. Para concluir, STAEN está demostrando ser herramientas confiables y efectivas para la evaluación de las funciones cognitivas en adultos, proporcionando más validez ec[CA] Les funcions cognitives inclouen tots els processos a través dels quals un individu percep, registra, manté, manipula, usa i expressa informació que està involucrada en qualsevol activitat quotidiana. Les principals ferramentes estandarditzades es poden dividir en tres grups principals: escales curtes de proves de seguiment cognitiu: qüestionaris, bateries neuropsicológiques generals i proves específiques. Estes ferramentes estan ben validades i són confiables, però, en l'última dècada, diverses investigacions han demostrat que alguns pacients poden realitzar bé estes proves neuropsicológiques, inclús quan tenen dificultats significatives per a adaptar els seus comportaments a les activitats de la vida diària. D'acord amb açò, més recentment, un nou enfocament ha augmentat substancialment, la qual cosa podria proporcionar una major validesa ecològica en l'avaluació de les capacitats cognitives funcionals que l'enfocament estandarditzat: l'ús de sistemes tecnològics avançats per a l'avaluació neuropsicológica (STAEN). STAEN es referix a un conjunt de dispositius i aplicacions de software com ara proves computaritzades, jocs divertits i interactius de fantasia (JS) i / o sistemes de realitat virtual simulada (RV) i / o augmentada (RA) que van més enllà de les proves d'avaluació tradicionals i que brinden la possibilitat de presentar estímuls controlats i dinàmics, en entorns ecològicament vàlids i segurs. Partint d'estes premisses, l'objectiu principal de la tesi era dissenyar, desenrotllar i validar un SG 2D no inmersiu versus un JS 3D inmersiu i una activitat de la vida diària en un entorn 3D RV inmersiu versus un RA per a l'avaluació de funcions cognitives, comparant l'eficàcia i efectivitat d'ells. El primer estudi 2D va incloure 354 subjectes sans i es van trobar correlacions entre el joc i els mètodes tradicionals, la qual cosa suggerix que el joc podria ser una ferramenta vàlida per a avaluar les funcions cognitives en adults. El segon estudi, va comparar la versió 2D versus una versió 3D STAEN, va involucrar a 94 subjectes sans i va mostrar que la versió 3D va ser capaç de generar temps més baixos i respostes correctes més altes que la 2D, la qual cosa suggerix evidència inicial de l'eficàcia d'un sistema més inmersiu en comparació amb un sistema no-inmersiu. Encara que este resultat destaca una possible limitació en l'ús de diferents sistemes tecnològics a causa de les diferències en els dos mètodes d'interacció (el sistema 2D va aplicar el ratolí i el teclat; els controladors de dos mans virtuals 3D) i el registre de dades de latència de hardware i software. Respecte a la variabilitat individual en edat, gènere i educació, les troballes van mostrar consistència amb la literatura de referència. Específicament, els més jóvens van mostrar un major rendiment que els majors; nivells educatius més alts reflectits en una millor puntuació i sobre gènere, els resultats van mostrar un panorama més compost. A més, per a millorar la validesa ecològica de l'avaluació, l'últim estudi d'esta tesi va comparar el rendiment conductual i les respostes fisiològiques, durant una tasca de cuina ecològica, entre un sistema virtual i un sistema augmentat en 50 subjectes sans. La tasca de cuinar va consistir en 4 nivells que van augmentar en dificultat. A mesura que el nivell va augmentar, van aparéixer activitats addicionals. Els resultats de comportament van mostrar que els temps són sempre més baixos en realitat virtual que en RA, augmentant constantment d'acord amb la dificultat de les tasques. Respecte a les respostes fisiològiques, les troballes van mostrar que la condició RA va produir més excitació i activació individual que la realitat virtual. Per a concloure, STAEN està demostrant ser ferramentes confiables i efectives per a l'avaluació de les funcions cognitives en adults, proporcionant més validesa ecològica i objectivitat que els mètodes tradicio[EN] Cognitive functions include all the processes through which an individual perceives, records, maintains, manipulates, uses and expresses information that are involved in any everyday activity. The main standardized tools can be divided in three main groups: short scales of cognitive tracking tests - questionnaires, general neuropsychological batteries, and specific tests. These tools are well-validated and reliable but, in the last decade, several research have shown that some patients can perform these neuropsychological tests well, even when they have significant difficulties in adapting their behaviours to daily life activities. According to this, more recently, a new approach has substantially increased, potentially providing a higher ecological validity in functional cognitive abilities assessment than standardized approach: the use of advanced technological systems for neuropsychological assessment (ATSNA). ATSNA refer to a set of devices and software applications such as computerized tests, fun and interactive fantasy serious games (SG), and/or simulated virtual (VR) and/or augmented (AR) reality systems that go beyond traditional assessment tests and that supply the possibility to deliver controlled and dynamic stimuli, in ecologically valid, and secure environments. Starting from these premises, the main objective of the thesis was to design, develop, and validate a non-immersive 2D SG versus an immersive 3D SG and a daily life activity in an immersive 3D VR environment versus an AR for the assessment of cognitive functions, comparing the efficacy and effectiveness of them. The first 2D study involved 354 healthy subjects and correlations were found between the game and traditional methods, suggesting that the game could be a valid tool for assessing cognitive functions in adults. The second study, compared 2D versus a 3D ATSNA version, it involved 94 healthy subjects and showed that 3D version was able to generate lower times and higher correct answers that the 2D, suggesting initial evidence of efficacy of a more immersive system compared to a non-immersive system. Although this result highlights a potential limitation on using different technological systems due to the differences on the two interaction methods (the 2D system applied mouse and keyboard; the 3D two virtual hands' controllers) and hardware and software latency data recording. Regarding individual variability on age, gender, and education, the findings showed consistency with the reference literature. Specifically, younger showed higher performance that older; higher educational levels reflected on a better score and about gender, results showed a more composite panorama. Furthermore, to enhance the ecological validity of assessment, the last study of this thesis compared the behavioural performance and physiological responses, during an ecological cooking task, between a virtual and an augmented system on 50 healthy subjects. The cooking task consisted of 4 levels that increased in difficulty. As the level increased, additional activities appeared. The behavioural results showed that times are always lower in VR than in AR, increasing constantly in accordance with the difficulty of the tasks. Regarding physiological responses, the findings showed that AR condition produced more individual excitement and activation than VR. To conclude, ATSNA are proving to be reliable and effective tools for the assessment of cognitive functions in adults, providing more ecological validity and objectivity than traditional methods of assessment.Chicchi Giglioli, IAM. (2020). Novel supports to the assessment of cognitive functions through the combined use of technologies and subjective and objective measurements [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/139075TESISCompendi