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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
121

Labyrinth psychotica : simulating psychotic phenomena

Kanary Nikolova, Jennifer January 2016 (has links)
This thesis forms a valuable tool of analysis, as well as an important reference guide to anyone interested in communicating, expressing, representing, simulating and or imagining what it is like to experience psychotic phenomena. Understanding what it is like to experience psychotic phenomena is difficult. Those who have experience with it find it hard to describe, and those who do not have that experience find it hard to envision. Yet, the ability to understand is crucial to the interaction with a person struggling with psychotic experiences, and for this help is needed. In recent years, the psychosis simulation projects Mindstorm, Paved with Fear, Virtual Hallucinations and Living With Schizophrenia have been developed as teaching and awareness tools for mental health workers, police, students and family members, so that they can better understand psychotic phenomena. These multimedia projects aim to improve understanding of what a person in psychosis is going through. This thesis represents a journey into taking a closer look at their designs and comparing them to biographical and professional literature. In doing so, throughout the chapters, a set of considerations and design challenges have been created that need to be taken into account when simulating psychosis. After a series of artistic case study labyrinths, Suicide Pigeon, Intruder, and Intruder 2.0, two final ‘do-it-yourself-psychosis’ projects have been created that have taken the aspects collected into account: The Labyrinth and The Wearable. Together these two projects form experiences that may be considered analogous to psychotic experiences. My original contribution to knowledge lies, on the one hand, within the function that both The Labyrinth and The Wearable have on a person’s ability to gain a better understanding of what it feels like to be in psychosis, and on the other hand within the background information provided on the context and urgency of psychosis simulation, how the existing simulations may be improved, and how labyrinthine installation art may contribute to these improvements.
122

Augmented virtuality:transforming real human activity into virtual environments

Pouke, M. (Matti) 11 August 2015 (has links)
Abstract The topic of this work is the transformation of real-world human activity into virtual environments. More specifically, the topic is the process of identifying various aspects of visible human activity with sensor networks and studying the different ways how the identified activity can be visualized in a virtual environment. The transformation of human activities into virtual environments is a rather new research area. While there is existing research on sensing and visualizing human activity in virtual environments, the focus of the research is carried out usually within a specific type of human activity, such as basic actions and locomotion. However, different types of sensors can provide very different human activity data, as well as lend itself to very different use-cases. This work is among the first to study the transformation of human activities on a larger scale, comparing various types of transformations from multiple theoretical viewpoints. This work utilizes constructs built for use-cases that require the transformation of human activity for various purposes. Each construct is a mixed reality application that utilizes a different type of source data and visualizes human activity in a different way. The constructs are evaluated from practical as well as theoretical viewpoints. The results imply that different types of activity transformations have significantly different characteristics. The most distinct theoretical finding is that there is a relationship between the level of detail of the transformed activity, specificity of the sensors involved and the extent of world knowledge required to transform the activity. The results also provide novel insights into using human activity transformations for various practical purposes. Transformations are evaluated as control devices for virtual environments, as well as in the context of visualization and simulation tools in elderly home care and urban studies. / Tiivistelmä Tämän väitöskirjatyön aiheena on ihmistoiminnan muuntaminen todellisesta maailmasta virtuaalitodellisuuteen. Työssä käsitellään kuinka näkyvästä ihmistoiminnasta tunnistetaan sensoriverkkojen avulla erilaisia ominaisuuksia ja kuinka nämä ominaisuudet voidaan esittää eri tavoin virtuaaliympäristöissä. Ihmistoiminnan muuntaminen virtuaaliympäristöihin on kohtalaisen uusi tutkimusalue. Olemassa oleva tutkimus keskittyy yleensä kerrallaan vain tietyntyyppisen ihmistoiminnan, kuten perustoimintojen tai liikkumisen, tunnistamiseen ja visualisointiin. Erilaiset anturit ja muut datalähteet pystyvät kuitenkin tuottamaan hyvin erityyppistä dataa ja siten soveltuvat hyvin erilaisiin käyttötapauksiin. Tämä työ tutkii ensimmäisten joukossa ihmistoiminnan tunnistamista ja visualisointia virtuaaliympäristössä laajemmassa mittakaavassa ja useista teoreettisista näkökulmista tarkasteltuna. Työssä hyödynnetään konstrukteja jotka on kehitetty eri käyttötapauksia varten. Konstruktit ovat sekoitetun todellisuuden sovelluksia joissa hyödynnetään erityyppistä lähdedataa ja visualisoidaan ihmistoimintaa eri tavoin. Konstrukteja arvioidaan sekä niiden käytännön sovellusalueen, että erilaisten teoreettisten viitekehysten kannalta. Tulokset viittaavat siihen, että erilaisilla muunnoksilla on selkeästi erityyppiset ominaisuudet. Selkein teoreettinen löydös on, että mitä yksityiskohtaisemmasta toiminnasta on kyse, sitä vähemmän tunnistuksessa voidaan hyödyntää kontekstuaalista tietoa tai tavanomaisia datalähteitä. Tuloksissa tuodaan myös uusia näkökulmia ihmistoiminnan visualisoinnin hyödyntämisestä erilaisissa käytännön sovelluskohteissa. Sovelluskohteina toimivat ihmiskehon käyttäminen ohjauslaitteena sekä ihmistoiminnan visualisointi ja simulointi kotihoidon ja kaupunkisuunnittelun sovellusalueilla.
123

[en] IMMERSIVE VIDEO AND 3D VIRTUAL REALITY: A PATH FOR IMMERSIVE DESIGN / [pt] O VÍDEO IMERSIVO E A REALIDADE VIRTUAL 3D: UM CAMINHO PARA O DESIGN DE IMERSÃO

MARCOS LUIS BARBATO 15 December 2017 (has links)
[pt] Este trabalho disserta sobre características subjetivas e técnicas do Vídeo Imersivo (VI) e da Realidade Virtual 3D (3DVR). Observa, particularmente, aspectos de uma estratégia do design realista com que ambientes são concebidos e produzidos em projetos de Realidade Virtual (VR). O Uncanny Valley (UV) é um corolário do processo criativo de personagens, representado por uma curva conceitual em que a conexão emocional ou empatia entre audiência e personagens varia de forma não linear e não diretamente proporcional em função do realismo com que estes personagens são concebidos. Dado o protagonismo dos ambientes em projetos VR, haveria um Uncanny Valley of Places? Lugares, ambientes, espaços e a cenografia virtual estão sujeitos a uma estranheza em Realidade Virtual? Neste trabalho, são apresentados dados de três ciclos de pesquisa a partir três experimentos VR que buscam responder a estas questões: 1) O experimento Immersive Bike (IB), que integra estímulos visuais em VI com estímulos hapticos sinestésicos passivos; 2) A aplicação Rio 360 VR; aplicativo imersivo; 3) Pesquisa centrada no usuário, que compara diretamente aplicações VI e 3DVR. Este trabalho aponta caminhos para apoiar o processo criativo do Designer de Interação, demonstrando que sensação de imersão não é função direta do maior ou menor realismo com que as imagens são produzidas e sim é potencializada a partir da conexão multimodal do repertório de sensações dos usuários e sua conexão com as histórias propostas pelas aplicações imersivas. / [en] This dissertation aims to present subjective and technical characteristics of Immersive Video (IV) and 3D Virtual Reality (3DVR). Observes, particularly, aspects related to a realism approach design strategy for VR environment s conception. The Uncanny Valley (UV) is a corollary of illustrated character s creative process, a conceptual curve that represents the variation of the emotional connection with characters related to its realistic properties conception. The UV refers to the base of a parabolic positive curve of this dynamic relation between empathy and realism, on which is detected a weirdness or an uncanny as much realistic the character seams. Does VR environments are subjected to an analog UV? Is there an Uncanny Valley of Places? Do places, ambients, spaces and virtual scenography is subjected to an uncanny in Virtual Reality? This work presents results of three cycles of research based on three VR experiments that aim to respond these questions: 1) The Immersive Bike experiment, which design integrates IV with kinesthetic haptics; 2) Rio 360 VR0, an immersive aplication for mobile interaction; 3) Human-centered research that compares IV and 3DVR applications. This work points a path to the Interaction Designer creative process, proposing that the immersive sensation is not directly proportional of how realistic an immersive image is produced, but is potentiated by the multimodal user s connection with the storytelling of the immersive aplication.
124

CREAME: CReation of Educative Affordable Multi-surface Environments

García Sanjuan, Fernando 06 April 2019 (has links)
Los juegos serios colaborativos tienen un impacto positivo en el comportamiento y el aprendizaje, pero siguen desarrollándose para plataformas tecnológicas tradicionales como videoconsolas y ordenadores de sobremesa o portátiles, los cuales han sido identificados como sub-óptimos para niños en diversos estudios. En su lugar, el uso de dispositivos móviles como tabletas y teléfonos inteligentes presenta diversas ventajas: son económicamente asequibles, están ampliamente distribuidos, y pueden ser transportados, lo cual permite la actividad física y poder iniciar un juego sin necesitar que los usuarios se trasladen a una localización fija, especialmente dedicada para tal fin. Además, combinar varios de estos dispositivos y coordinar la interacción entre ellos en lo que se denomina Entorno Multi-Pantalla (EMP) proporciona beneficios adicionales para la colaboración tales como una mayor escalabilidad, conciencia del espacio de trabajo, paralelismo y fluidez de las interacciones. La interacción en estos entornos multi-tableta es por tanto un aspecto crítico. Los dispositivos móviles están diseñados para ser interactuados mediante el toque de los dedos principalmente, lo cual es muy sencillo y directo, pero está normalmente limitado a la pequeña dimensión de las pantallas, lo que puede conllevar la oclusión de la pantalla y la infrautilización del espacio periférico. Por esta razón, esta tesis se centra en la exploración de otro mecanismo de interacción que puede complementar al táctil: interacciones tangibles alrededor del dispositivo. Las interacciones tangibles están basadas en la manipulación de objetos físicos, lo que presenta un valor adicional en la educación de los niños puesto que resuena con los manipulativos educativos tradicionales y permite la exploración del mundo físico. Por otra parte, la explotación del espacio que envuelve a las pantallas tiene diversos beneficios adicionales para actividades educativas colaborativas: reducida oclusión de la pantalla (lo cual puede incrementar la conciencia del espacio de trabajo), el uso de objetos tangibles como contenedores de información digital que puede ser transportada de forma continua entre dispositivos, y la identificación de un determinado estudiante a través de la codificación de su ID en un operador tangible (lo cual facilita el seguimiento de sus acciones y progreso durante el juego). Esta tesis describe dos enfoques distintos para construir juegos educativos colaborativos en EMPs utilizando interacciones tangibles alrededor de los dispositivos. Una, denominada MarkAirs, es una solución óptica aérea que no necesita ningún hardware adicional aparte de las tabletas excepto diversas tarjetas de cartón impresas. La otra, Tangibot, introduce un robot tangiblemente controlado y otro atrezo físico en el entorno, y se basa en tecnología RFID. Ambas interacciones son respectivamente evaluadas, y se observa que MarkAirs es usable y poco exigente tanto para adultos como para niños, y que se pueden realizar con éxito gestos de grano fino encima de las tabletas con ella. Además, al aplicarse en juegos colaborativos, puede ayudar a reducir la oclusión de las pantallas y la interferencia entre las distintas acciones de los usuarios, lo cual es un problema que puede surgir en este tipo de escenarios cuando solamente se dispone de interacciones táctiles. Se evalúa un juego educativo colaborativo con MarkAirs con niños de educación primaria, y se concluye que este mecanismo es capaz de crear experiencias de aprendizaje colaborativo y de presentar un valor añadido en términos de experiencia de usuario, aunque no en eficiencia. Con respecto a Tangibot, se muestra que controlar colaborativamente un robot móvil mediante unas palas tangibles con cierta precisión es factible para niños a partir de los tres años de edad, e incluso para personas mayores con un deterioro cognitivo leve. Además, proporciona una experiencia divertida / Collaborative serious games have a positive impact on behavior and learning, but the majority are still being developed for traditional technological platforms, e.g., video consoles and desktop/laptop computers, which have been deemed suboptimal for children by several studies. Instead, the use of handheld devices such as tablets and smartphones presents several advantages: they are affordable, very widespread, and mobile---which enables physical activity and being able to engage in a game without requiring users to gather around a fixed, dedicated, location. Plus, combining several of these devices and coordinating interactions across them in what is called a Multi-Display Environment (MDE) brings on additional benefits to collaboration like higher scalability, awareness, parallelism, and fluidity of the interaction. How to interact with these multi-tablet environments is therefore a critical issue. Mobile devices are designed to be interacted mainly via touch, which is very straightforward but usually limited to the small area of the displays, which can lead to the occlusion of the screen and the underuse of the peripheral space. For this reason, this thesis focuses on the exploration of another interaction mechanism that can complement touch: tangible around-device interactions. Tangible interactions are based on the manipulation of physical objects, which have an added value in childhood education as they resonate with traditional learning manipulatives and enable the exploration of the physical world. On the other hand, the exploitation of the space surrounding the displays has several potential benefits for collaborative-learning activities: reduced on-screen occlusion (which may increase workspace awareness), the use of tangible objects as containers of digital information that can be seamlessly moved across devices, and the identification of a given student through the encoding of their ID in a tangible manipulator (which facilitates the tracking of their actions and progress throughout the game). This thesis describes two different approaches to build collaborative-learning games for MDEs using tangible around-device interactions. One, called MarkAirs, is a mid-air optical solution relying on no additional hardware besides the tablets except for several cardboard printed cards. The other, Tangibot, introduces a tangible-mediated robot and other physical props in the environment and is based on RFID technology. Both interactions are respectively evaluated, and it is observed that MarkAirs is usable and undemanding both for adults and for children, and that fine-grained gestures above the tablets can be successfully conducted with it. Also, when applied to collaborative games, it can help reduce screen occlusion and interference among the different users' actions, which is a problem that may arise in such settings when only touch interactions are available. A collaborative learning game with MarkAirs is evaluated with primary school children, revealing this mechanism as capable of creating collaborative learning experiences and presenting an added value in user experience, although not in performance. With respect to Tangibot, we show how collaboratively controlling a mobile robot with tangible paddles and achieving certain precision with it is feasible for children from 3 years of age, and even for elderly people with mild cognitive impairment. Furthermore, it provides a fun experience for children and maintains them in a constant state of flow. / Els jocs seriosos col·laboratius tenen un impacte positiu en el comportament i l'aprenentatge, però continuen sent desenvolupats per a plataformes tecnològiques tradicionals com videoconsoles i ordinadors de sobretaula o portàtils, els quals han sigut identificats com sub-òptims per a xiquets en diversos estudis. D'altra banda, l'ús de dispositius mòbils com ara tabletes i telèfons intel·ligents presenta diversos avantatges: són econòmicament assequibles, estan àmpliament distribuïts i poden ser transportats, la qual cosa permet l'activitat física i poder iniciar un joc sense necessitat de què els usuaris es traslladen a una localització fixa i especialment dedicada per a eixa finalitat. A més, combinar diversos d'estos dispositius i coordinar la interacció entre ells en el que es denomina Entorn Multi-Pantalla (EMP) proporciona beneficis addicionals per a la col·laboració tals com una major escalabilitat, consciència de l'espai de treball, paral·lelisme i fluïdesa de les interaccions. La interacció amb estos entorns multi-tableta és per tant crítica. Els dispositius mòbils estan dissenyats per a ser interactuats mitjançant tocs de dit principalment, mecanisme molt senzill i directe, però està normalment limitat a la reduïda dimensió de les pantalles, cosa que pot ocasionar l'oclusió de la pantalla i la infrautilització de l'espai perifèric. Per aquesta raó, la present tesi se centra en l'exploració d'un altre mecanisme d'interacció que pot complementar al tàctil: interaccions tangible al voltant dels dispositius. Les interaccions tangibles estan basades en la manipulació d'objectes físics, cosa que presenta un valor addicional en l'educació dels xiquets ja que ressona amb els manipulatius tradicionals i permet l'exploració del món físic. D'altra banda, l'explotació de l'espai que envolta a les pantalles té diversos beneficis addicionals per a activitats educatives col·laboratives: reduïda oclusió de la pantalla (la qual cosa pot incrementar la consciència de l'espai de treball), l'ús d'objectes tangibles com a contenidors d'informació digital que pot ser transportada de forma continua entre dispositius, i la identificació d'un estudiant determinat a través de la codificació de la seua identitat en un operador tangible (cosa que facilita el seguiment de les seues accions i progrés durant el joc). Aquesta tesi descriu dos enfocaments distints per a construir jocs educatius col·laboratius en EMPs utilitzant interaccions tangibles al voltant dels dispositius. Una, denominada MarkAirs, és una solució òptica aèria que no precisa de cap maquinari addicional a banda de les tabletes, exceptuant diverses targetes de cartró impreses. L'altra, Tangibot, introdueix un robot controlat tangiblement i attrezzo físic addicional en l'entorn, i es basa en tecnologia RFID. Ambdues interaccions són avaluades respectivament, i s'observa que MarkAirs és usable i poc exigent tant per a adults com per a xiquets, i que es poden realitzar gestos de granularitat fina dalt de les tabletes amb ella. A més a més, en aplicar-se a jocs col·laboratius, pot ajudar a reduir l'oclusió de les pantalles i la interferència entre les distintes accions dels usuaris, problema que pot aparèixer en este tipus d'escenaris quan solament es disposa d'interaccions tàctils. S'avalua un joc educatiu col·laboratiu amb MarkAirs amb xiquets d'educació primària, i es conclou que aquest mecanisme és capaç de crear experiències d'aprenentatge col·laboratiu i de presentar un valor afegit en termes d'experiència d'usuari, tot i que no en eficiència. Respecte a Tangibot, es mostra que controlar conjuntament un robot mòbil mitjançant unes pales tangibles amb certa precisió és factible per a xiquets a partir de tres anys i inclús per a persones majors amb un lleu deteriorament cognitiu. A més, proporciona una experiència divertida per als xiquets i els manté en un estat constant de flow. / García Sanjuan, F. (2018). CREAME: CReation of Educative Affordable Multi-surface Environments [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/101942 / TESIS
125

Photometric registration of indoor real scenes using an RGB-D camera with application to mixed reality / Recalage photométrique de scènes réelles d’intérieurs à l’aide d’une caméra RGB-D avec application à la réalité mixte

Jiddi, Salma 11 January 2019 (has links)
L'objectif principale de la Réalité Mixte (RM) est de donner aux utilisateurs l'illusion que les objets virtuels et réels coexistent indistinctement dans le même espace. Une illusion efficace nécessite un recalage précis entre les deux mondes. Ce recalage doit être cohérent du point de vue géométrique et photométrique. Dans cette thèse, nous proposons de nouvelles méthodes de recalage photométrique pour estimer l'illumination et la réflectance de scènes réelles. Plus précisément, nous proposons des approches en nous attaquant à trois grands défis : (1) utilisation d'une seule caméra RGB-D. (2) estimation des propriétés de réflectance diffuse et spéculaire. (3) estimation de la position 3D et de la couleur de sources lumineuses dynamiques multiples. Dans notre première contribution, nous considérons des scènes réelles d’intérieurs où la géométrie et l'éclairage sont statiques. En observant la scène à partir d’une caméra mobile, des réflexions spéculaires peuvent être détectées tout au long de la séquence d'images RGB-D. Ces indices visuels sont très instructifs sur l'éclairage et la réflectance des surfaces des scènes. Par conséquent, nous les modélisons pour estimer à la fois les propriétés de réflectance diffuse et spéculaire ainsi que la position 3D de sources lumineuses multiples. Notre algorithme permet d'obtenir des résultats de RM convaincants tels que des ombres virtuelles réalistes ainsi qu'une suppression correcte de la spécularité réelle. Les ombres sont omniprésentes et représentent l’occultation de la lumière par la géométrie existante. Elles représentent donc des indices intéressants pour reconstituer les propriétés photométriques de la scène. La présence de texture dans ce contexte est un scénario critique. En effet, la séparation de la texture et des effets d'éclairage est souvent gérée par des approches qui nécessitent l’intervention de l'utilisateur ou qui ne répondent pas aux exigences du temps de traitement de la réalité mixte. Nous abordons ces limitations et proposons une méthode d'estimation de la position et de l'intensité des sources lumineuses. L'approche proposée gère les lumières dynamiques et fonctionne en temps quasi-réel. L'existence d'une source lumineuse est plus probable si elle est soutenue par plus d'un indice visuel. Nous abordons donc le problème de l'estimation des propriétés d’éclairage et de réflectance en analysant conjointement les réflexions spéculaires et les ombres projetées. L'approche proposée tire parti de l'information apportée par les deux indices pour traiter une grande variété de scènes. Notre approche est capable de traiter n'importe quelle surface texturée et tient compte à la fois des sources lumineuses statiques et dynamiques. Son efficacité est démontrée par une gamme d'applications, incluant la réalité mixte et la re-texturation. La détection des ombres projetées et des réflexions spéculaires étant au cœur de cette thèse, nous proposons finalement une méthode d'apprentissage approfondi pour détecter conjointement les deux indices visuels dans des scènes réelles d’intérieurs. / The overarching goal of Mixed Reality (MR) is to provide the users with the illusion that virtual and real objects coexist indistinguishably in the same space. An effective illusion requires an accurate registration between both worlds. This registration must be geometrically and photometrically coherent. In this thesis, we propose novel photometric registration methods to estimate the illumination and reflectance of real scenes. Specifically, we propose new approaches which address three main challenges: (1) use of a single RGB-D camera. (2) estimation of both diffuse and specular reflectance properties. (3) estimation of the 3D position and color of multiple dynamic light sources. Within our first contribution, we consider indoor real scenes where both geometry and illumination are static. As the sensor browses the scene, specular reflections can be observed throughout a sequence of RGB-D images. These visual cues are very informative about the illumination and reflectance of scene surfaces. Hence, we model these cues to recover both diffuse and specular reflectance properties as well as the 3D position of multiple light sources. Our algorithm allows convincing MR results such as realistic virtual shadows and correct real specularity removal. Shadows are omnipresent and result from the occlusion of light by existing geometry. They therefore represent interesting cues to reconstruct the photometric properties of the scene. Presence of texture in this context is a critical scenario. In fact, separating texture from illumination effects is often handled via approaches which require user interaction or do not satisfy mixed reality processing time requirements. We address these limitations and propose a method which estimates the 3D position and intensity of light sources. The proposed approach handles dynamic light sources and runs at an interactive frame rate. The existence of a light source is more likely if it is supported by more than one cue. We therefore address the problem of estimating illumination and reflectance properties by jointly analysing specular reflections and cast shadows. The proposed approach takes advantage of information brought by both cues to handle a large variety of scenes. Our approach is capable of handling any textured surface and considers both static and dynamic light sources. Its effectiveness is demonstrated through a range of applications including real-time mixed reality and retexturing. Since the detection of cast shadows and specular reflections are at the heart of this thesis, we further propose a deep-learning framework to jointly detect both cues in indoor real scenes.
126

Motion Capture mit optisch-magnetischem Trackingsystem in VR-Applikationen

Steger, Daniel 25 July 2004 (has links)
Motion capture is the process to record the movement of a human. To accomplish this, a hybrid tracking system is used. It combines an optic tracking system with a magnetic one to compensate shortcomings and effectively use their advantages. Another part of this work copes with the conversion of the tracking data into skeletal information and related topics like skeleton definition, skeleton fitting or parameterization of joint rotations. / Mittels Motion Capture werden die Bewegungen eines Menschen in computerlesbare Form überführt. Dazu wird ein hybrides Trackingsystem verwendet, das durch Kombination eines optischen mit einem magnetischen System entsteht und die Schwächen der Einzelsysteme kompensiert. Neben der Realisierung dieses Hybridsystems steht die Übertragung der gewonnenen Bewegungsdaten auf ein Skelettmodell und damit verbundene Fragen, wie Skelettdefinition, Skelettanpassung oder Beschränkung der Gelenkrotationen im Vordergrund.
127

A HOPE FOR STROKE REHABILITATION : EXPLORING THE REHATT MIXED REALITY APPLICATION

Widengren, Mattias January 2021 (has links)
Unilateral spatial neglect (USN) is a common disorder after stroke. An application especially developed for stroke rehabilitation, the RehAtt Mixed Reality (MR) intends to train cognitive and motor functions that are affected by USN, by the means of interactive 3D games played in mixed reality, through smart glasses. The present study targets one specific cognitive function, namely spatial attention, and compares individual performances in one of the games (scenarios) to performances in a widely used test for detection of deficits in spatial attention – the Posner test. The hypothesis is that user reaction times in the RehAtt MR scenario correlates with user reaction times in the Posner test. Another test, including a questionnaire, to validate the usability of the RehAtt MR is also conducted. The sample for the usability test and questionnaire includes a total of 74 participants (47 women, 27 men, M = 39.6 years of age), of which 29 individuals (13 women, 16 men, M = 35 years of age) carried out the experimental part of the study. The results suggest that there is a significant correlation, r(27) = .411, p = .027, between reaction times in the Posner test and the scenario in the RehAtt MR, and that the product usability shows high quality. It is concluded that the results support that the scenario explored in the RehAtt MR trains spatial attention, although further research is needed for full validation. / Unilateraltspatialt neglekt (USN) är en vanlig funktionsnedsättning efter stroke. En applikation som utvecklats speciellt för strokerehabilitering - RehAtt Mixed Reality (MR) - har som mål att träna kognitiva och motoriska funktioner som är påverkade av USN, med hjälp av 3D-spel som spelas i mixed reality, genom smarta glasögon. Den aktuella studien siktar in sig på en specifik kognitiv funktion – spatial uppmärksamhet – och jämför individuella prestationer i ett av spelen i RehAtt MR med prestationer i ett vanligt, ofta använt test för att upptäcka nedsättningar i spatial uppmärksamhet – Posner-testet. Hypotesen är att användares reaktionstider i spelet i RehAtt MR korrelerar med användares reaktionstider i Posner-testet. Ett annat test, inklusive en enkät, görs också, för att validera användbarheten i RehAtt MR. 74 deltagare (47 kvinnor, 27 män, M = 39.6 år) finns med i användbarhetstestet och enkäten, av vilka 29 individer (13 kvinnor, 16 män, M = 35 år) medverkade i den experimentella delen av studien. Resultaten indikerar att det är en signifikant korrelation, r(27) = .411, p = .027, mellan reaktionstiderna i Posner-testet och spelet i RehAtt MR, och att användbarheten hos produktenvisar hög kvalitet. Slutsatsen är att vad som hittats i den aktuella studien stödjer idéen att spelet i RehAtt MR tränar spatial uppmärksamhet, även om vidare studier krävs för en full validering.
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Driving in Virtual Reality : Investigations in Effects of Latency and Level of Virtuality

Blissing, Björn January 2016 (has links)
When developing new active safety systems or improving existing systems, conducting performance evaluations is necessary. By performing these evaluations during early development stages, potential problems can be identified and mitigated before the system moves into the production phase. Testing active safety systems can be difficult since the characteristic scenarios may have complex interactions. Using real vehicles for performing these types of scenarios is difficult, expensive, and potentially dangerous. Alternative methods, such as using inflatable targets, scale models, computer simulations or driving simulators, also suffer from drawbacks. Consequently, using virtual reality as an alternative to the traditional methods has been proposed. In this case, a real vehicle is driven while wearing a head-mounted display that presents the scenario to the driver. This research aims to investigate the potential of such technology. Specifically, this work investigates how the chosen technology affects the driver. This investigation has been conducted through a literature review. A test platform was constructed, and two user studies using normal drivers were performed. The first study focused on the effects of visual time delays on driver behavior. This study revealed that lateral behavior changes with added time delays, whereas longitudinal behavior appears unaffected. The second study investigated how driver behavior is affected by different modes of virtuality. This study demonstrated that drivers perceived mixed reality as more difficult than virtual reality. The main contribution of this work is the detailed understanding of how time delays and different modes of virtuality affect drivers. This is important knowledge for selecting which scenarios are suitable for evaluation using virtual reality. / <p>The series name <em>Linköping Studies in Science and Technology Licentiate Thesis</em> is incorrect. The correct series name is <em>Linköping Studies in Science and Technology Thesis</em>.</p>
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Human Systems Integration of an Extravehicular Activity Space Suit Augmented Reality Display System

Mitra, Paromita 10 August 2018 (has links)
During an extravehicular activity (EVA), the role of an astronaut involves a multitude of complex tasks. Whether that task is a science experiment aboard the International Space Station, or traversing extraterrestrial terrain – attention, communication, and instruction are essential. As an aid, augmented reality (AR) can portray suit informatics and procedures within line-of-sight while minimizing attentional loss. Currently, there exists little research highlighting the human systems considerations to qualify AR systems for space suit applications. This study quantifies user interface (UI) and human performance measures for an AR prototype on the Mark III space suit. For user testing, 21 military pilots and personnel (11 men, 10 women) evaluated UI search tasks and completed a series of AR-instructed EVA dexterity tasks in an elevated luminosity, background clutter, and workload scenario. UI results suggest correlations for readability and usability; whereas, human performance results provide situational awareness, workload, and task performance data.
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Peripheral visual cues and their effect on the perception of egocentric depth in virtual and augmented environments

Jones, James Adam 09 December 2011 (has links)
The underestimation of depth in virtual environments at mediumield distances is a well studied phenomenon. However, the degree by which underestimation occurs varies widely from one study to the next, with some studies reporting as much as 68% underestimation in distance and others with as little as 6% (Thompson et al. [38] and Jones et al. [14]). In particular, the study detailed in Jones et al. [14] found a surprisingly small underestimation effect in a virtual environment (VE) and no effect in an augmented environment (AE). These are highly unusual results when compared to the large body of existing work in virtual and augmented distance judgments [16, 31, 36–38, 40–43]. The series of experiments described in this document attempted to determine the cause of these unusual results. Specifically, Experiment I aimed to determine if the experimental design was a factor and also to determine if participants were improving their performance throughout the course of the experiment. Experiment II analyzed two possible sources of implicit feedback in the experimental procedures and identified visual information available in the lower periphery as a key source of feedback. Experiment III analyzed distance estimation when all peripheral visual information was eliminated. Experiment IV then illustrated that optical flow in a participant’s periphery is a key factor in facilitating improved depth judgments in both virtual and augmented environments. Experiment V attempted to further reduce cues in the periphery by removing a strongly contrasting white surveyor’s tape from the center of the hallway, and found that participants continued to significantly adapt even when given very sparse peripheral cues. The final experiment, Experiment VI, found that when participants’ views are restricted to the field-of-view of the screen area on the return walk, adaptation still occurs in both virtual and augmented environments.

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