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Peña, Pitarch E. (Esteve). "Virtual human hand: grasping strategy and simulation." Doctoral thesis, Universitat Politècnica de Catalunya, 2008. http://hdl.handle.net/10803/6995.
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La mano humana es una herramienta muy completa, capaz de adaptarse a diferentes superficies y formas, y también tocar y coger. Es una conexión directa entre el mundo exterior y el cerebro. I.Kant (filosofo alemán) definió la mano como una extensión del cerebro.En esta tesis, nosotros hemos construido una mano virtual para simular la mano humana lo más realísticamente posible. Basado en la anatomía de la mano, hemos diseñado una mano con 25 grados de libertad (DOF), con cuatro de esos grados de libertad localizados en la unión carpometacarpal, para el dedo anular y el meñique. Estos cuatro grados de libertad permiten la simulación de la mano humana cuando esta se arquea. El dedo gordo ha sido diseñado con 5 DOF, los dedos, índice y medio tienen 4 DOF, la unión metacarpofalangeal tiene dos, y las uniones interfalangeales próxima y distal tienen uno cada una. Para los dedos anular y meñique, los 4 DOF tienen las mismas uniones más los cuatro descritos arriba.
El método de Denavit-Hartenberg (D-H) fue aplicado, debido a que cada dedo fue considerado como un rayo, esto es, una cadena cinemática abierta, con las uniones consideradas "revolutas". Las tablas D-H para cada dedo fueron mostradas y la aplicación de la cinemática directa e inversa permitió calcular todos los ángulos para cada unión [q1 . . . q25]T .
Antes de coger cualquier objeto, nuestro sistema comprueba si el objeto esta en el espacio de la mano, mediante el análisis del espacio de trabajo.
Se ha implementado un algoritmo semi-inteligente orientado a las tareas para las cuales el objeto ha sido diseñado, con el fin de tomar una decisión, una vez el usuario ha escogido el objeto y su tarea inherente. El algoritmo para coger ha sido implementado en un escenario virtual.
The human hand is the most complete tool, able to adapt to different surfaces and shapes and to touch and grasp. It is a direct connection between the exterior world and the brain. I. Kant (German philosopher) defined how the hand is an extension of the brain.
In this dissertation, we built a virtual human hand to simulate the human hand as realistically as possible. Based on the anatomy of the hand, we designed a hand with 25 degrees of freedom (DOF), with four of these degrees located in the carpometacarpal joint for the ring and small fingers. These four degrees permit the simulation of the human hand when it is arched. The thumb was designed with 5 DOF, the index and middle fingers have 4 DOF, in the metacarpophalangeal joint has two, and in the proximal interphalangeal joint and in the distal interphalangeal joint each have one. For the ring and small fingers, the 4 DOF are in similar joints plus as the four described above.
The Denavit-Hartenberg (D-H) method was applied because each finger was considered a ray, i.e., an open chain, with joints approximated to revolute joints. The D-H tables for each finger were shown, and the application of forward and inverse kinematics permit the calculation of all angles for each joint [q1 . . . q25]T .
Before grasping any object, our system checks the reachability of the object with workspace analysis.
Semi-intelligent task-oriented object grasping was implemented for making a decision once the user chooses the object and the task inherent to the object. The grasping algorithm was implemented in a virtual environment.
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Peña, Pitarch Esteban. "Virtual Human Hand: Grasping Strategy and Simulation." Doctoral thesis, Universitat Politècnica de Catalunya, 2008. http://hdl.handle.net/10803/6995.
Full textAbstract:
La mano humana es una herramienta muy completa, capaz de adaptarse a diferentes superficies y formas, y también tocar y coger. Es una conexión directa entre el mundo exterior y el cerebro. I.Kant (filosofo alemán) definió la mano como una extensión del cerebro.En esta tesis, nosotros hemos construido una mano virtual para simular la mano humana lo más realísticamente posible. Basado en la anatomía de la mano, hemos diseñado una mano con 25 grados de libertad (DOF), con cuatro de esos grados de libertad localizados en la unión carpometacarpal, para el dedo anular y el meñique. Estos cuatro grados de libertad permiten la simulación de la mano humana cuando esta se arquea. El dedo gordo ha sido diseñado con 5 DOF, los dedos, índice y medio tienen 4 DOF, la unión metacarpofalangeal tiene dos, y las uniones interfalangeales próxima y distal tienen uno cada una. Para los dedos anular y meñique, los 4 DOF tienen las mismas uniones más los cuatro descritos arriba.El método de Denavit-Hartenberg (D-H) fue aplicado, debido a que cada dedo fue considerado como un rayo, esto es, una cadena cinemática abierta, con las uniones consideradas "revolutas". Las tablas D-H para cada dedo fueron mostradas y la aplicación de la cinemática directa e inversa permitió calcular todos los ángulos para cada unión [q1 . . . q25]T .Antes de coger cualquier objeto, nuestro sistema comprueba si el objeto esta en el espacio de la mano, mediante el análisis del espacio de trabajo.Se ha implementado un algoritmo semi-inteligente orientado a las tareas para las cuales el objeto ha sido diseñado, con el fin de tomar una decisión, una vez el usuario ha escogido el objeto y su tarea inherente. El algoritmo para coger ha sido implementado en un escenario virtual.The human hand is the most complete tool, able to adapt to different surfaces and shapes and to touch and grasp. It is a direct connection between the exterior world and the brain. I. Kant (German philosopher) defined how the hand is an extension of the brain.In this dissertation, we built a virtual human hand to simulate the human hand as realistically as possible. Based on the anatomy of the hand, we designed a hand with 25 degrees of freedom (DOF), with four of these degrees located in the carpometacarpal joint for the ring and small fingers. These four degrees permit the simulation of the human hand when it is arched. The thumb was designed with 5 DOF, the index and middle fingers have 4 DOF, in the metacarpophalangeal joint has two, and in the proximal interphalangeal joint and in the distal interphalangeal joint each have one. For the ring and small fingers, the 4 DOF are in similar joints plus as the four described above.The Denavit-Hartenberg (D-H) method was applied because each finger was considered a ray, i.e., an open chain, with joints approximated to revolute joints. The D-H tables for each finger were shown, and the application of forward and inverse kinematics permit the calculation of all angles for each joint [q1 . . . q25]T .Before grasping any object, our system checks the reachability of the object with workspace analysis.Semi-intelligent task-oriented object grasping was implemented for making a decision once the user chooses the object and the task inherent to the object. The grasping algorithm was implemented in a virtual environment.
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Nasser, Bilal. "A virtual hand assessment system for efficient outcome measures of hand rehabilitation." Thesis, University of Strathclyde, 2016. http://digitool.lib.strath.ac.uk:80/R/?func=dbin-jump-full&object_id=27529.
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Vulgari, Sofia Kiriaki. "Hand Gesture based Telemedicine enabled by Mobile VR." Thesis, Linnéuniversitetet, Institutionen för datavetenskap och medieteknik (DM), 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-88810.
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Virtual Reality (VR) is a highly evolving domain and is used in anincreasing number of areas in today's society. Among the technologiesassociated with VR and especially mobile VR, is hand tracking and handgesture recognition. Telemedicine is one of the elds where VR is startingto thrive, and so the concept of adding the use of hand gestures came to bein order to explore the possibilities that can come from it. This researchis conducted with the development of a prototype application that usessome of the most emerging technologies. Manomotion's hand trackingand hand gesture recognition algorithms, and Photon's servers and developerkit, which makes multi-user applications achievable, allowed theconceptual idea of the prototype to become reality. In order to test itsusability and how potential users perceive it, a user study with 24 participantswas made, 8 of which were either studying or working in themedical eld. Additional expert meetings and observations from the userstudy also contributed to ndings that helped show how hand gesturescan aect a doctor consultation in Telemedicine. Findings showed thatthe participants thought of the proposed system as a less costly and timesaving solution, and that they felt immersed in the VR. The hand gestureswere accepted and understood. The participants did not have dicultieson learning or executing them, and had control of the prototype environment.In addition, the data showed that participants considered it to beusable in the medical eld in the future.
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Chen, Hui, and 陳輝. "Building panoramas from photographs taken with a hand-held camera." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2002. http://hub.hku.hk/bib/B31242923.
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Chen, Hui. "Building panoramas from photographs taken with a hand-held camera /." Hong Kong : University of Hong Kong, 2002. http://sunzi.lib.hku.hk/hkuto/record.jsp?B23668064.
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Yang, Xibei, and 杨曦贝. "A hand input-based approach to intuitive human-computer interactions in virtual reality." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2010. http://hub.hku.hk/bib/B45160557.
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Cruea, Mark Douglas. "The Virtual Hand: Exploring the Societal Effects of Video Game Industry Business Models." Bowling Green State University / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1320430304.
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Lu, Yang. "Tour Into Painting : System Design for Virtual Exhibition of Chinese Hand-Scroll Painting." Thesis, Ecole centrale de Nantes, 2022. https://tel.archives-ouvertes.fr/tel-03921024.
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La peinture chinoise à rouleau (CHSP) est une forme de peinture chinoise typique. La manière correcte de regarder une CHSP est de la faire défiler à la main. Regarder une CHSP est considéré comme une expérience fantastique de visite dans son monde diégétique. Dans les expositions actuelles de CHSP, ces points ne sont pas bien représentées. Premièrement, la plupart des CHSP sont présentés dans des boîtes en verre. Les spectateurs ne peuvent pas les manipuler en les faisant défiler. Deuxièmement, l'expérience de la visite d'une peinture n'est interprétée que par de simples annotations. Les spectateurs ne peuvent pas acquérir une expérience complète à partir de ces annotations. Cette recherche a exploré l'utilisation de la réalité virtuelle (RV) pour combler ces lacunes. L'objectif de cette recherche est de développer un système d'exposition basé sur la RV, qui peut simuler de manière synchrone l'expérience de visualisation de l'ancien spectateur dans le monde réel et l'expérience de visite dans le monde diégétique. Le système est présenté comme une application de RV qui comprend une CHSP interactive qui peut être manipulé selon les principes originaux. De manière synchrone, l'utilisateur de la RV sera déplacé en fonction de son point de focalisation sur la CHSP virtuelle, puis un monde diégétique englobant et aléatoire sera construitThe Chinese Hand-Scroll Painting (CHSP) is a typical Chinese painting form. The proper way to view a CHSP is scrolling it by hands. Watching a CHSP is considered as a fantasy experience of touring in its diegetic world. In current exhibitions of CHSPs, these points are not well represented. First, most of CHSPs are presented in glass boxes. Viewers can not manipulate it in scrolling manner. Second, the experience of touring into painting is only interpreted by simple annotations. Viewers can not gain a full experience based on them. This research aims to implementing these shortcoings by developing a VR-based exhibition system, which can synchronously simulate the ancient viewer's viewing experience in the real world and the touring experience in the diegetic world. The system is presented as a VR application that includes an interactive CHSP that can be manipulated according to the original principles. In a synchronous way, the VR user will be moved according to his focus point on the virtual CHSP, and then, an encompassing, random diegetic world will be built
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Achibet, Merwan. "Contributions to the design of novel hand-based interaction techniques for virtual environments." Thesis, Rennes, INSA, 2015. http://www.theses.fr/2015ISAR0031/document.
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Faire directement usage de nos mains pour explorer des environnements virtuels et interagir avec leur contenu permet une interaction à la fois naturelle et convaincante. Dans ce manuscrit de thèse, nous visons à améliorer l’interaction avec les mains dans le contexte de la Réalité Virtuelle en abordant deux défis majeurs : (1) faciliter le contrôle de modèles de mains articulées et (2) fournir des sensations haptiques au travers d’interfaces accessibles. Nous abordons tout d’abord l’interaction au travers de mains virtuelles articulées et proposons deux méthodes pour faciliter leur contrôle. Premièrement, nous réduisons leurs nombreux degrés de liberté de façon à pouvoir exploiter des interfaces tactiles courantes. Le système qui en résulte permet aux utilisateurs de contrôler une main virtuelle en réalisant des gestes sur la surface de la tablette. Ensuite, nous adoptons une autre approche et séparons les degrés de liberté des mains virtuelles entre deux interfaces haptiques contrôlées en parallèle. Par cette distribution des contrôles et des retours de force, les utilisateurs sont exposés à des effets haptiques variés, autrement réservés à des interfaces haptiques coûteuses. Nous abordons ensuite le sujet du retour haptique pour différents types d’interaction avec les mains. Pour cela, nous combinons des retours passifs à des retours pseudo-haptiques en tant qu’alternative à l’usage d’interfaces actives complexes et encombrantes. Dans un premier temps, nous considérons l’interaction avec les bras et proposons une armature élastique attachés à l’utilisateur qui fournit un retour de force égocentrique tout en conservant sa mobilité. Nous abordons ensuite le sujet de la saisie d’objets virtuels et proposons un nouveau paradigme d’interaction basé sur une interface élastique qui reproduit les mouvements de préhension et fournit un retour adapté et modulable par un effet pseudo-haptique. Finalement, nous considérons la manipulation fine avec les doigts et proposons un exosquelette passif qui les contraint séparément, associé à un retour pseudo-haptique multi-doigt simulant l’interaction avec des matériaux hétérogènesDirectly using our hands to explore virtual environments and interact with their contents produces a natural and compelling interaction. In this thesis, we propose contributions to improve hand-based interaction in the context of Virtual Reality by considering two main challenges: (1) improving the control of articulated hand models, and (2) providing haptic sensations with accessible techniques. We first address the challenge of interacting through realistic, articulated virtual hands and propose two methods for easing their control. As a first step, we reduce the degrees of freedom of complex hand models in order to make multi-finger interaction possible with common multi-touch interfaces. The resulting system allows users to control a virtual hand by performing gestures over a tactile tablet. Then, we take another approach and separate the degrees of freedom of one virtual hand between two haptic interfaces handled in parallel. Through this distribution of controls and feedback, users are exposed to a variety of haptic effects, otherwise restricted to complex haptic workstations. We then address the challenge of providing haptic sensations during hand-based interaction. To do so, we introduce different techniques that combine passive haptic feedback and pseudo-haptics as an alternative to complex and cumbersome active interfaces. We consider various types of interaction at different scales, starting with coarse interaction with the arm through an elastic armature that provides an egocentric and mobile haptic feedback. We then focus on object grasping and manipulation and propose an interaction paradigm that relies on elastic input devices for reproducing grasping gestures and perceiving modulable haptic properties through crossmodal feedback. Finally, we consider fine multi-finger manipulation and we propose a passive exoskeleton that constrains the digits individually, associated to a multi-finger pseudo-haptic feedback for simulating complex interaction with heterogeneous materials
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Georgiadis, Abraham. "VR Gaming - Hands On : The use and effects of bare hand gestures as an interaction method in multiplayer Virtual Reality Games." Thesis, Linnéuniversitetet, Institutionen för medieteknik (ME), 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-66863.
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The field of virtual reality (VR) is getting increasing attention from the scientific community and it is being portrayed by advertisements as the user interface (UI) of the future. This is a fair statement since the prior uses of VR that used to exist only in fiction movies and books are now widely available in many forms and settings to the public. One of the most interesting outcomes from this technological evolution is that now VR can be experienced through the use of a mobile phone and the addition of some inexpensive means typically in a form of a headset. The combination of the phone’s screen as attached to the headset creates a form of Head Mounted Display (HMD) which can be utilized in order for the user to be immersed within a virtual environment (VE). The argument here is that even if the means to get access to VR are cheap, this should not be the case with the experience as well. On the contrary, the low entry requirements in combination with a high quality experience are the basis for the medium's success and further adoption by the users. More specifically, the capability of utilizing a three dimensional space (3D) should not limit the medium’s use on just that but instead, this space should be used in order to offer immersive environments which make the user feel as if he is there. There are many factors that contribute to that result and significant progress has been made to some such as the quality of screen or other hardware parts that allow the user get immersed into the virtual scenery, however, little progress has been made towards the conceptual means that allow the user of better experiencing this VE. Most of the VR applications so far are specifically designed for a single user session. This creates an isolation of the user from any other type of communities which further increases the stigma of VR being a solitary experience. Another issue is the interaction method that is available to users in order to interact with the VE. The use of buttons in most of the available headsets is a counter intuitive method for a person to interact with an environment that wants to be called real. The technological advancements in the field of image processing have resulted in many new methods of interaction and multimodal manipulation within VE and it would be worthy of exploring their effects on the user experience (UX) when used as an interaction method. For these reasons, this thesis used the case of VR games as a setting to study how UX can be enhanced from its current state by introducing a bare hand gesture interaction method and expanding the VR setting in order to host two users in shared VE. Two individual studies were conducted where user feedback was collected in order to describe the effects of this approach in both a qualitative and quantitative manner. As results indicate, by utilizing gesture analysis on a headset equipped with a smartphone, it is possible to offer a natural and engaging solution for VR interaction capable of rich UXs while maintaining a low entry level for the end users. Finally, the addition of another player significantly affected the experience by influencing the emotional state of the participants in the game and further enforcing their feeling of presence within the VE.
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Gasparyan, Arsen. "Cost-Efficient Video Interactions for Virtual Training Environment." Bowling Green State University / OhioLINK, 2007. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1182533924.
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Richter, Fabian [Verfasser], and Rainer [Akademischer Betreuer] Lienhart. "Virtual Reconstruction of Hand-Torn Documents using Discriminative Models / Fabian Richter. Betreuer: Rainer Lienhart." Augsburg : Universität Augsburg, 2015. http://d-nb.info/1080772928/34.
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Günther, Tobias, Erich Querner, and Rainer Groh. "A head-in-hand metaphor for user-centric direct camera control in virtual reality." ACM, 2020. https://tud.qucosa.de/id/qucosa%3A74888.
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The explorative examination of constructed 3D models in immersive environments requires suitable user-centric interaction methods. Especially novel concepts for virtual camera control can offer advantages, e.g. for the analysis of model details. We extend the known concept of the camera-in-hand metaphor and implement a multidimensional viewport control technique that can be used with common head-mounted displays and VR-controllers. With our head-in-hand view the user is able to control the virtual camera directly by hand without losing the flexibility of head movements. To ensure convenient operation, the method restricts special rotation parameters and smoothes jerky gestures of the user hand. Inaddition, we discuss implications and improvement potential of the proposed concept as well as adverse effects on the user, such as motion sickness.
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Abi-Rached, Habib. "Stereo-based hand gesture tracking and recognition in immersive stereoscopic displays /." Thesis, Connect to this title online; UW restricted, 2006. http://hdl.handle.net/1773/6012.
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Dahlgren, Mikael. "Object Selection by Relative Hand to Cursor Mapping : Design and Evaluation of a 2D-Object Selection Technique for Hand Tracking in Virtual Environments." Thesis, KTH, Skolan för elektroteknik och datavetenskap (EECS), 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-292107.
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Hand and tracker jitter negatively affect performance with ray-casting in virtual environments, making it difficult to acquire small objects which require high levels of precision. This study evaluates an alternative target acquisition technique for 2D-interfaces in virtual environments with relative hand-to-cursor mapping. Trade-offs between the relative hand-to-cursor mapping and ray-casting are explored in comparative evaluation, utilizing Fitts's law, SUS-surveys and interviews. The results demonstrate that relative hand-to-cursor mapping performs equal to ray-casting while also allowing higher precision in certain selection tasks.Strålföljning påverkas negativt av darrning i händer och spårteknik i virtuella miljöer vilket gör det svårt att markera objekt som kräver hög precision. Denna studie utvärderar en alternativ teknik till strålföljning for objektmarkering i 2D-granssnitt i virtuella miljöer kallad relativ hand till musmarkör mappning. Avvägning mellan dessa två tekniker utvärderas i en jämförande studie med hjälp av Fitts's lag, SUS-undersökning och intervjuer. Resultaten demonstrerar att relativ hand till murmarkor mappning presterar jämförbart med strålföljning och tillåter samtidigt högre precision i särskilda objektmarkeringsuppgifter.
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Ma, Sha. "Development and evaluation of an electromyography biofeedback-based virtual reality system for hand motion rehabilitation." Thesis, University of Central Lancashire, 2010. http://clok.uclan.ac.uk/19302/.
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Individuals who have upper limb movement problems include people with cerebral palsy (CP) and stroke victim . Both thes conditions lead to difficulties in daily activities such as reaching, gra ping etc. Loss of motor function can be improved or recovered via relevant target specific movement rehabilitation. This r search aims to d velop and evaluate an electromyography (EMG) biofeedback based virtual reality (VR) system targeted towards CP and stroke patients that could provide an engaging and effective way to practice and improve hand and arm motion functions. VR, which could provide a repetitive multimodal taskorient d r habilitation environment for patients to undertake elf-training in safety, is con id red to be a suitabl tool for medical health rehabilitation. Using EMG biofeedback in rehabilitation could provide pati nts with opportunities to improve their ability by ass ssing th ir muscle activity r spons and learning self-control of mov m nt during specific training tasks. Th syst m development incorporat s concepts f om motor learning, visual art and programming, and provid s visual and audio feedback that guides the us r' movem nt to becom smoother and more fficient. Using compo ite multiple feedback in upp r limb r habilitation enables th individual with upp r limb probl m to perceiv similar r al-world p rformanc in th virtual world. Howev r, it i r cognised that such fe dback might cause information overload, 1 ading to the individual feeling confused and distract d during training. The necessity of involving healthy subject in f asibility tudies is also recognised. Therefore, thi study focuses on healthy subjects to investigate the effectiveness of separate function-specific fe dback training exercises in order to overcome the information overload problem. Two s ts of xp riments based on 2D display and 3D display were carried out in thi research. A total of sixty healthy subjects participated in the experiments, thirty for the 2D display tests and thirty for the 3D display tests. The developed EMG biof edback based VR system provided the participants with position, orientation, and muscle activity response information. This allow d combined task-oriented multiple feedback which aimed to improve the performance in the virtual environment. In order to preempt and deal with the information overload problem, three prior individual fe dback pre-training game-like tasks were designed based on the distinctive functions of the individual VR interactive interfaces (magnetic track r and EMG system). As in video games, where preparative modes are provided, and the player can learn the key functions and the game scenario through prior practice, so as to improve their performance in the full game. This allows the multimodal and multiform fe dback training exercises are broken down into individual function-specific feedback exercises. The training tasks were designed in the form of gam -like tasks, which could offer better motivation and allow easier hierarchical delivery. Candle lighting, ball balancing and cup grasping game-like tasks, which are position movement, orientation movement and muscle contraction pre-training tasks respectively, were designed based on th distinctive function of magnetic tracking and EMG systems. The balloon shooting main game, which is re-engineered ba ed on a tutorial provided by th XNA game studio, was developed for th multiform feedback training task. The d veloped game-like VR rehabilitation tasks could make th information from the biological level visible to participant with multimodal and multiform feedback. In both 2D and 3D display tests, th r are two experimental groups with pre-training prior to th main game and a control group with th main task only. The empirical results of both 2D and 3D display t t indicate that the developed EM G biofe d back based VR system and tasks are useful to improv the ability of ome of th upp r limb activitie , and th prior individual feedback pre-training tasks are h lpful for b tt r performance in the main multiform fe dback task . This tudy show d that the information ov rload occurring in th integrat d VR syst m with multiple forms of£ edback can b ov rcom with prop rly design pre -training tasks.
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Sidenmark, Ludwig. "Immersive Eye Tracking Calibration in Virtual Reality Using Interactions with In-game Objects." Thesis, KTH, Skolan för datavetenskap och kommunikation (CSC), 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-209431.
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This thesis aims to investigate an eye tracking calibration method in virtual reality where users’ visual attention from eye-hand coordination is used when interacting with in-game items. This could potentially allow eye tracking calibration without interrupting the virtual experience, in comparison with traditional eye tracking calibration which is cumbersome, disruptive, and requires the user’s full attention. A user study was conducted with 15 participants in which they were tasked to complete three different interactions. The interactions tested were a knob, a slider and a liftable cube. Where in the virtual environment the participants were looking during the interactions was recorded and processed to enable comparison. The processed data was analysed to find factors that influenced the calibration method. Additionally, the results was analysed to find at what point during the interactions that has the most consistent eye tracking fixations on the interacted item, and therefore most potential for eye tracking calibration. The results showed that when the participant is interacting with the item and the interacted item is stationary, we received a fixation for around 60% of all trials at any time. When the interacted item was moving the results indicated a lower percentage. To increase this number, the gaze data should be filtered instead of using raw gaze data in order to avoid flickering from the eye tracker. Regarding factors that influence the calibration method, the choice of interaction has a big impact on the method’s success where interactions in which the interacted item is stationary has more potential. Additionally, interactions that take longer time and requires precision in order to complete the interaction positively influences the potential of the calibration method. The surrounding virtual environment also has an influence, as a more distracting environment can negatively impact the calibration method.Denna avhandling ämnar att att undersöka en kalibreringsmetod för ögonspårning i virtuell verklighet där användarnas visuella uppmärksamhet från ögon och hand koordination används när man interagerar med objekt i den virtuella verkligheten. Detta kan möjliggöra kalibrering av ögonspårning utan att avbryta den virtuella upplevelsen, i jämförelse med traditionell kalibrering som är besvärlig, störande och kräver användarens fulla uppmärksamhet. En användarstudie genomfördes med 15 deltagare där de hade till uppgift att slutföra tre olika interaktioner. De testade interaktionerna var en knopp, en slider och en lyftbar kub. Deltagarnas blick spelades in under interaktionerna och analyserades för att möjliggöra jämförelse. Den bearbetade data analyserades för att hitta faktorer som påverkar kalibreringsmetoden. Dessutom analyserades resultaten för att hitta vid vilken tidpunkt under interaktionerna som hade de mest konsekventa ögonfixeringarna på objektet de interagerade med och därmed störst potential för kalibrering av ögonspårning. Resultaten visade att när deltagaren interagerar med objektet och det interaktiva objektet är stillastående, fick vi en fixering för omkring 60% av alla försök under godtycklig tidpunkt. När det interaktiva objektet rörde sig, visade resultaten en lägre procentandel. För att öka antalet, ska blickdatan filtreras i stället för att använda rå blickdata för att undvika att flicker från ögonspåraren. När det gäller faktorer som påverkar kalibreringsmetoden har valet av interaktion stor inverkan på metodens framgång, där interaktioner där det interaktiva objektet är stationärt har större potential. Dessutom påverkar interaktioner som tar längre tid och kräver precision för att slutföra interaktionen kalibreringsmetodens potential positivt. Den omgivande virtuella miljön har också inflytande, eftersom en mer distraherande miljö kan negativt påverka kalibreringsmetoden.
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Olofsson, Jakob. "Input and Display of Text for Virtual Reality Head-Mounted Displays and Hand-held Positionally Tracked Controllers." Thesis, Luleå tekniska universitet, Institutionen för system- och rymdteknik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-64620.
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The recent increase of affordable virtual reality (VR) head-mounted displays has led to many new video games and applications being developed for virtual reality environments. The improvements to VR technology has introduced many new possibilities, but has also introduced new problems to solve in order to make VR software as comfortable and as effective as possible. In this report, different methods of displaying text and receiving text input in VR environments are investigated and measured. An interactive user study was conducted to evaluate and compare the performance and user opinion of three different text display methods and four separate virtual keyboard solutions. Results revealed that the distance between text and user, with the same relative text size, significantly affected the ease of reading the text, and that designing a good virtual keyboard for VR requires a good balance of multiple factors. An example of such factors is the balance between precise control and the amount of physical exertion required. Additionally, the results suggest that the amount of previous experience with virtual reality equipment, and typing skill with regular physical keyboards, can meaningfully impact which solution is most appropriate.Den senaste tidens ökning av prisvärda virtual reality (VR) glasögon har lett till en ökning av spel och applikationer som utvecklas för virtual reality miljöer. Förbättringarna av VR tekniken har introducerat många nya möjligheter, men även nya problem att lösa för att skapa VR mjukvara som är så bekväm och effektiv som möjligt. I den här rapporten undersöks och mäts olika metoder för att visa samt ta emot text i VR miljöer. Detta undersöktes genom utförandet av en interaktiv användarstudie som utvärderade och jämförde effektiviteten och användaråsikter kring tre olika metoder för att visa text samt fyra olika virtuella tangentbordslösningar. Resultatet visade att avståndet mellan användaren och texten, med samma relativa textstorlek, avsevärt påverkade lättheten att läsa texten, samt att designen av ett bra virtuellt tangentbord för VR kräver en bra balans mellan flera faktorer. Ett exempel på sådana faktorer är balansen mellan noggrann kontroll och den fysiska ansträngning som krävs. Resultatet tyder även på att mängden av tidigare erfarenhet med virtual reality utrustning samt skicklighet att skriva med vanliga fysiska tangentbord betydligt kan påverka vilka lösningar som är mest passande för situationen.
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Marangoni, Matthew J. "Low Cost Open Source Modal Virtual Environment Interfaces Using Full Body Motion Tracking and Hand Gesture Recognition." Wright State University / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=wright1369256636.
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Mishra, Sankalp. "Use Of Virtual Reality Technology In Medical Training And Patient Rehabilitation." Wright State University / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=wright1559144258671291.
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Moore, Charles H. "Grasping Embodiment: Haptic Feedback for Artificial Limbs." University of Cincinnati / OhioLINK, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1617107153868166.
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Bales, Delaney M. "An Ergonomics Investigation of the Application of Virtual Reality on Training for a Precision Task." DigitalCommons@CalPoly, 2017. https://digitalcommons.calpoly.edu/theses/1757.
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Virtual reality is rapidly expanding its capabilities and accessibility to consumers. The application of virtual reality in training for precision tasks has been limited to specialized equipment such as a haptic glove or a haptic stylus, but not studied for handheld controllers in consumer-grade systems such as the HTC Vive. A straight-line precision steadiness task was adopted in virtual reality to emulate basic linear movements in industrial operations and disability rehabilitation. This study collected the total time and the error time for the straight-line task in both virtual reality and a physical control experiment for 48 participants. The task was performed at four different gap widths, 4mm, 5mm, 6mm, and 7mm, to see the effects of virtual reality at different levels of precision. Average error ratios were then calculated and analyzed for strong associations to various factors. The results indicated that a combination of Environment x Gap Width factors significantly affected average error ratios, with a p-value of 0.000.
This human factors study also collected participants’ ratings of user experience dimensions, such as difficulty, comfort, strain, reliability, and effectiveness, for both physical and virtual environments in a questionnaire. The results indicate that the ratings for difficulty, reliability, and effectiveness were significantly different, with virtual reality rating consistently rating worse than the physical environment. An analysis of questionnaire responses indicates a significant association of overall environment preference (physical or virtual) with performance data, with a p-value of 0.027.
In general, virtual reality yielded higher error among participants. As the difficulty of the task increased, the performance in virtual reality degraded significantly. Virtual reality has great potential for a variety of precision applications, but the technology in consumer-grade hardware must improve significantly to enable these applications. Virtual reality is difficult to implement without previous experience or specialized knowledge in programming, which makes the technology currently inaccessible for many people. Future work is needed to investigate a larger variety of precision tasks and movements to expand the body of knowledge of virtual reality applications for training purposes.
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Voth, Elizabeth Christine. "Your (virtual) trainer in the palm of your hand : efficacy of a theory-based exercise application to enhance exercise adherence." Thesis, University of British Columbia, 2015. http://hdl.handle.net/2429/54789.
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Background: Use of mobile health (mHealth) technology is on an exponential rise. mHealth applications (apps) have the capability to reach a large number of individuals, but until now have lacked the integration of evidence-based theoretical constructs to increase exercise behaviour in users.
Objective: The purpose of this study was to assess the effectiveness of a theory-based, self- monitoring app on exercise and self-monitoring behaviour over 8-weeks.
Methods: Fifty-six adults (Mage = 40 years ± 13) were randomly assigned to either receive the mHealth app (experimental; n = 28), or control (control; n = 28). All participants engaged in an exercise goal setting session at baseline. Experimental condition participants received weekly SMS (short-messaging service) text messages grounded in social cognitive theory and were encouraged to self-monitor exercise bouts on the app on a daily basis. Exercise behaviour, frequency of self-monitoring exercise behaviour, self-efficacy to self-monitor, and self- management of exercise behaviour was collected at baseline and post-testing.
Results: Engagement in exercise bouts was greater in the experimental condition (M = 7.24, SD = 3.40) as compared to the control condition (M = 4.74, SD = 3.70, P = .03, d = .70) at week-8 post-testing. Frequency of self-monitoring increased significantly over the 8-week investigation between the experimental and control conditions (P < .001, partial η² = .599), with the experimental condition self-monitoring significantly more at post (M = 6.00, SD = 0.93) in comparison to the control condition (M = 1.95, SD = 2.58, P < .001, d = 2.10). Self-efficacy to self-monitor, and perceived self-management of exercise behaviour were unaffected by this intervention.
Conclusions: The successful integration of social cognitive theory into an mHealth exercise self- monitoring app provides support for future research to: i) feasibly integrate theoretical constructs into existing exercise apps, and ii) increase self-monitoring and exercise behaviour.Graduate Studies, College of (Okanagan)
Graduate
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Forsberg, Erik. "Interacting with information visualizations in virtual reality : Motion tracked hand controller interaction for common filtering operations in a VR information visualization application." Thesis, KTH, Skolan för datavetenskap och kommunikation (CSC), 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-210043.
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As we are heading into immersive virtual reality environments for different purposes - entertainment being the most prominent lately - we should consider how we design interactive information visualizations for VR. Is it wise to hold onto the same elements of interaction with which we are familiar from contemporary web-based interfaces? The study explores this question along with others, to explore ways to conduct familiar filtering operations known from web environments, in VR. An interactive information visualization application in VR was created to evaluate two web-inspired interaction methods used for filtering data. Thirteen users participated in the tests, in which each participant worked through eight predetermined tasks as well as one open-ended task. Qualitative feedback was gathered both through think-alouds during the tasks and in semi-structured interviews when the test had been concluded. Quantitative data was gathered in the application, containing logs of usage statistics. Results show that using web-inspired interaction methods to carry out filtering operations in VR helped the participants to understand the functionality of the interactions. By implementing haptic and visual feedback, natural interactions can be imitated which according to the results of the study generally is perceived as helpful while making the interactions feel more natural. Designing the interaction methods to function like previously known interactions (such as ones found in web interfaces) helped the participants to understand the functionality of the filters.I och med framfarten av VR och dess olika användningsområden – där underhållning gått i bräschen på senare tid – borde vi fundera på hur vi designar interaktiva informationsvisualiseringar för VR. Är det klokt att hålla fast vid samma interaktionselement som vi känner igen från webbaserade gränssnitt? Studien utforskar denna fråga tillsammans med andra, för att utforska sätt att genomföra bekanta filtreringsoperationer som känns igen från webbmiljöer, i VR. En interaktiv informationsvisualiseringsapplikation i VR skapades för att utvärdera två webbinspirerade interaktionsmetoder som användes för att filtrera data. Tretton användare deltog i studien, där varje deltagare tog sig igenom åtta förbestämda uppgifter samt en öppen uppgift. Kvalitativ återkoppling samlades in både via think-alouds under uppgifterna samt i semistrukturerade intervjuer när testet hade avslutats. Kvantitativa data samlades in i applikationen och innehöll användningsstatistik. Resultaten visar att användandet av webbinspirerade interaktionsmetoder för att genomföra filtreringsoperationer i VR hjälpte deltagarna att förstå interaktionens funktionalitet. Genom att implementera haptisk och visuell feedback kan naturliga interaktioner efterliknas, vilket enligt studiens resultat uppfattas som hjälpsamt samtidigt som interaktionerna kändes mer naturliga. Att utforma interaktionsmetoderna för att efterlikna de som återfinns i webbgränssnitt hjälpte deltagarna att förstå filtrens funktionalitet.
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Neshaug, Vegar. "Computerised Methods and Device for Intuitive Use of the Human Hand for Touching and Re-shaping of Three-Dimensional Virtual Objects." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for datateknikk og informasjonsvitenskap, 2010. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-12606.
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Today, the use of the mouse and keyboard input devices to interfacewith the computer is common almost regardless for what end the computeris used. This is no less true for users who daily work in three-dimensionalmodelling. Because of this, there is a signicant threshold for individualsbeginning three-dimensional modelling before being able to form even themost rudimentary of objects. A possible approach to lowering this thresh-old is to bridge the gap between traditional sculpting and virtual sculptingby utilizing the full range of human hand motion when interfacing withthe computer. This work review the status of Human-Computer Interaction devicesand methods, and set out to design and implement a low-cost data gloveprototype. A polygon mesh deformation method is developed which demonstratesthe functionality of the glove and system design. The work constitutes a useful platform for further academic work inthis eld.
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Karlsson, Fredrik, and Marcus Lundberg. "Designriktlinjer för handinteraktion för att stödja immersion i VR : En studie om att skapa riktlinjer för design av handinteraktion för VR för att stödja immersion." Thesis, Högskolan i Halmstad, Akademin för informationsteknologi, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-35373.
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Virtuell verklighet (VR) har börjat användas i större utsträckning av människor inomområden som utbildning och underhållning. För att VR ska uppfattas som en seriösplattform för att skapa utbildnings- och underhållningstjänster, är en känsla avimmersion en viktig del av användarupplevelsen. Det finns idag olika metoder för attinteragera med VR men de saknar upplevelsen av att vara naturliga och realistiska.Handinteraktion anses vara ett naturligt sätt för människor att interagera med VR och harförutsättningar för att stödja immersion. Trots att handinteraktion anses vara ett bra sättatt interagera med VR finns det idag inga riktlinjer som underlättar för att designa tjänstermed handinteraktion. För att undersöka hur handinteraktion kan designas för att stödjaimmersion i VR, har vi utgått från frågan:Hur kan handinteraktion designas för virtuell verklighet för att stödja immersion?Genom vår studie har vi identifierat aspekter som är viktiga för att handinteraktion skastödja immersion. Frågan studeras genom en designorienterad ansats med kvalitativadatainsamlingsmetoder som deltagartester, intervjuer och observationer. Testdeltagarnasom deltagit i studien är rekryterade baserat på deras tidigare erfarenheter av VR ochspel. Studien bidrar med kunskap om vad som är viktigt för att handinteraktion skauppfattas som naturligt och realistiskt för att stödja immersion när det används i VR.Virtual reality (VR) is becoming more commonly used by people in areas like educationand entertainment. However, for VR to be a serious platform for creating education andentertainment services, the sense of immersion is an important part of the userexperience. Today there are several methods to interact with VR, but they often lack thefeeling of being natural and realistic. Hand interaction is seen as a natural way for peopleto interact with VR and has potential to create immersion. However, even though handinteraction is seen to be a natural way of interacting with VR there’s no guidelinesavailable to facilitate the design of VR-services with hand interaction. To study how handinteraction can be designed to support immersion in VR, we’ve asked the question:“How can hand interaction be designed for virtual reality to support immersion?”Through our study, we have identified aspects that are important for hand interaction tobe able to support immersion. The question has been studied through a design orientedapproach with qualitative data gathering methods such as participant test, interviews andobservations. The test participants were recruited based on their previous experience ofVR and games. The study contributes with knowledge regarding what is important for
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Numfu, Manoch. "Une approche pour la préparation de formations aux gestes de la main en maintenance basées sur la réalité virtuelle." Thesis, Université Grenoble Alpes, 2020. http://www.theses.fr/2020GRALI071.
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Au cours de la dernière décennie, la technologie de la réalité virtuelle (RV) a évolué rapidement. Les environnements et appareils de la RV sont de plus en plus puissants et permettent des expériences utilisateur exceptionnelles. De tels environnements et dispositifs ont un potentiel énorme dans une grande variété d'applications industrielles, en particulier dans la formation à la maintenance. L'industrie, cependant, a encore des difficultés à obtenir des résultats de formation satisfaisants, principalement en raison de choix et de configurations inappropriés d'infrastructures de formation basées sur la RV. Afin de soutenir systématiquement le processus de préparation des formations de maintenance basées sur la réalité virtuelle, cette thèse propose un concept holistique pour la préparation de séquences de formation sur la maintenance basée sur la réalité virtuelle en mettant l'accent sur l'expérimentation, l'évaluation et la comparaison de différentes configurations de réalité virtuelle. Ce concept est appelé « Processus de préparation des formations basées sur la technologie de réalité virtuelle » (VR-TPP), et il a été mis en œuvre pour la validation dans des configurations non immersives et entièrement immersives. Parmi celles-ci, trois études de cas différentes montrent comment cette approche systématique aide les apprenants à trouver le processus de travail et les gestes de la main appropriés, ainsi que les formateurs à déterminer l'environnement de formation, la séquence et les instructions de travail les plus appropriés. Afin de tenir compte des spécificités des opérations de formation à la maintenance, un accent particulier a été mis sur la bonne saisie des gestes de la main et leur association avec différents types d'articulations mécaniques et le démontage des pièces mécaniques en fonction de leur adéquation. Ceci est considéré comme une contribution importante à la mise à niveau, au complément ou même au remplacement des instructions de travail traditionnelles sans participation active de l'utilisateur à des instructions de travail virtuelles offrant une expérience utilisateur. De plus, l'utilisation du concept VR-TPP permet également de révéler la cause des erreurs commises par les utilisateurs lorsqu'ils travaillent dans un environnement virtuel. Ces connaissances peuvent être réinjectées dans la conception du processus de formation ainsi que dans l'infrastructure. Outre les formations à la maintenance industrielle (donc au montage et au démontage), le concept peut être facilitateur pour de nombreuses autres applicationsOver the last decade, Virtual Reality (VR) technology has been evolving rapidly. VR environments and devices are more and more powerful and enable exceptional user experiences. Such environments and devices have a huge potential in a wide variety of industrial applications, in particular in maintenance training. Industry, however, still has difficulties achieving satisfactory training results, mainly due to inappropriate choices and setups of VR-based training infrastructures. In order to systematically support the preparation process of VR-based maintenance trainings, this thesis proposes a holistic concept for preparing VR-based maintenance training sequences with a focus on experimenting with, and evaluating and comparing different VR setups and configurations. This concept is called “Virtual Reality technology for Training Preparation Process” (VR-TPP), and it has been implemented for validation in both non-immersive and fully-immersive setups. Within those, three different case studies demonstrate how this systematic approach supports trainees in finding out the appropriate working process and hand gestures, as well as trainers in determining the most appropriate training environment, sequence and work instructions. In order to account for specificities in maintenance training operations, a particular focus has been directed on properly capturing hand gestures and associating them with different types of mechanical joints and the disassembly of mechanical parts according to their appropriateness. This is considered an important contribution to upgrading, complementing or even replacing traditional work instructions without active user involvement to virtual work instructions providing user experience. Furthermore, the use of the VR-TPP concept also helps revealing the cause of mistakes that users make when working in a virtual environment. From these insights, the learnings can be fed back into the design of the training process as well as the infrastructure. Apart from industrial maintenance (therefore assembly- and disassembly-) trainings, the concept enables and supports numerous other applications
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Wille, David-Alexander Ernst-Friedrich. "Virtual reality-based paediatric interactive therapy system (PITS) for improvement of arm and hand function in children with motor impairment : a pilot study /." [S.l.] : [s.n.], 2009. http://opac.nebis.ch/cgi-bin/showAbstract.pl?sys=000299326.
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Normand, Erwan. "Study of the perception and manipulation of virtual objects in augmented reality using wearable haptics." Electronic Thesis or Diss., Université de Rennes (2023-....), 2025. http://www.theses.fr/2025URENS002.
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Les dispositifs haptiques portables procurent des sensations tactiles tout en restant compacts. Ils ont été peu utilisés en réalité augmentée (RA), où le contenu virtuel est intégré à la perception du monde réel. Dans cette thèse, nous étudions leur utilisation pour améliorer les interactions de la main avec des objets virtuels et augmentés en RA. Nous commençons par étudier l'impact du rendu visuel sur la perception des textures vibrotactiles virtuelles qui augmentent des surfaces réelles touchées directement par le doigt. Nous proposons un système d’augmentation de textures visuo-haptiques à l'aide d'un casque de RA et d'un dispositif vibrotactile portable. Nous évaluons ensuite comment la rugosité perçue des textures augmentées diffère lorsqu'elles sont touchées via une main virtuelle, en réalité virtuelle (RV) et en RA, ou par sa propre main. Nous étudions alors le réalisme et la cohérence de la combinaison des textures augmentées visuelles et haptiques en RA. Nous étudions ensuite comment des retours sensoriels visuo-haptiques augmentant la main améliorent les performances et l’expérience utilisateur lors de la manipulation d'objets virtuels en RA. Nous commençons par étudier l'effet de six retours visuels de la main virtuelle comme augmentation de la main réelle. Nous évaluons ensuite deux techniques de contact vibrotactile à quatre endroits différents sur la main et nous les comparons à deux augmentations visuelles de la mainWearable haptic devices provide tactile sensations in a compact form. They have been little used in augmented reality (AR), where virtual content is integrated into real world perception. In this thesis, we investigate their use to enhance direct hand interaction with virtual and augmented objects in AR. First, we investigate how visual rendering affects the perception of vibrotactile texture augmentations of real surfaces directly touched by the finger. To this end, we propose a system for rendering visuo-haptic texture augmentations using an AR headset and a wearable vibrotactile device. Next, we evaluate how the perceived roughness of virtual textures differs when touched via a virtual hand vs. one's own hand, and in AR vs. virtual reality (VR). We then investigate the realism and coherence of combining visual and haptic texture augmentations in AR. Second, we investigate how visuo-haptic feedback as a hand augmentation improves the direct manipulation of virtual objects with the hand in AR, in terms of performance and usability. We study the effect of six visual feedback of the virtual hand as augmentation of the real hand. We then evaluate two vibrotactile contact techniques, provided at four different positions on the real hand and compare them to two visual hand augmentations
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Wang, Huiting. "How Will Different Control/Display Ratios Influence Muscle Fatigue and Game Experience in Virtual Reality Games?" Thesis, KTH, Skolan för datavetenskap och kommunikation (CSC), 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-192838.
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The dramatic evolvement of Virtual Reality (VR) technique in recent years has enabled a rapid growth of VR games. In order to provide intuitive interaction with a virtual world, VR hand controllers were developed. Since this kind of controller is based on hand movement, the risk of getting fatigued becomes very high. However, little current research has addressed the impact of fatigue generated by VR hand controllers. In this study, the influence of different Control/Display (C/D) ratios of hand controllers on muscle fatigue and the game experience in VR games was explored. Based on an established mobile VR fishing game, a test scenario was developed which uses Oculus Rift and Oculus Touch hand controller. A user study was conducted with 24 participants. The between subjects design was applied which spans three groups experiencing fishing with different C/D ratios (1.0, 0.5, 0.1 respectively). During the test, self- perceived fatigue data as well as game experience data was collected. The results showed that the fatigue was reduced gradually along with the decreasing of the C/D ratio, while different C/D ratios produced an impact on game experience depending on the margin between the exact ratio and 1.0. Based on the results, some implications for the design of VR games were introduced.De senaste årens stora intresse och fokuserade utveckling av tekniken för virtual reality (VR) har resulterat i en motsvarande utveckling av VR-spel. De tidigare använda kontrollerna (såsom mus/tangentbord eller spelkontroll) har visat sig inte vara tillräckliga utan det har utvecklats särskilda handkontroller för just VR för att intuitivt kunna interagera med en virtuell värld. Eftersom en sådan typ av kontroll baseras på handrörelser finns det en stor risk för att användarna att drabbas av muskeltrötthet. Det finns däremot mycket lite aktuell forskning med just detta fokus. I denna studie undersöks hur olika Control/Display (C/D)-förhållanden för VR-handkontroller påverkar muskeltröttheten och spelupplevelsen av VR-spel. Baserat på ett etablerat fiskespel i VR, skapades ett test-scenario som använde Oculus Rift och Oculus Touch (handkontrollen). Därefter genomfördes en användarstudie med 24 deltagare. Deltagarna var uppdelade i tre grupper och varje grupp testade spelet med olika C/D förhållanden (1.0, 0.5 och 0.1). Deltagarens egen uppfattning av trötthet, samt spelupplevelse, samlades in under användartesten. Resultaten visar att tröttheten minskar med minskande C/D-förhållande, samt att spelupplevelsen påverkas av C/D- förhållandet beroende på relationen mellan det exakta förhållandet och 1.0. Utifrån resultaten ges också några förslag för design av VR-spel.
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Shields, Christopher. "2D vs 3D in a touch-free hand gesture based interface : An exploration of how 2D and 3D visual aids affect a user’s ability to learn a new interface." Thesis, Linnéuniversitetet, Institutionen för medieteknik (ME), 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-37748.
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3D is a popular topic as an increasing amount of media and technology begin to support 3D interaction. With the rise of interest in 3D interaction, the question of why there is a demand and desire for 3D over 2D interaction becomes relevant. This thesis compares the differences between a 3D heads up display and a 2D heads up display for a touch free gesture based virtual keyboard. The gesture interface used in the tests is a way of communicating with a system using gestures of the hands tracked by a motion sensor. This thesis tested 16 users where half of the users used a 2D version of a heads up display and the other half used a 3D version of a heads up display. Both user groups were tested with identical conditions and in an identical environment. Raw statistical data was gathered from a logging mechanism in the interface and qualitative data was gathered from questionnaires and observation notes. The results from the experiment showed that the 2D and 3D heads up display gave very similar results. However, results also showed slightly better qualitative results from the 3D heads up display observation and questionnaire data. The conclusion indicated no clear advantage for the 2D version or the 3D version. The discussion shows that many other factors in the design process and selection of users, play a large role in the comparison of 2D vs 3D visualizations. Factors such as age and familiarity with different levels of technology are indicated to be contributing factors when comparing 2D vs 3D. The results and discussion hope to provide a starting point for future comparison research in the field of 2D compared to 3D visualization.
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Savallampi, Mattias. "The Role of Vision in Attributing the Sense of Part- and Full-Body Ownership During Anomalous Conditions." Thesis, Högskolan i Skövde, Institutionen för biovetenskap, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:his:diva-11363.
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Our bodies are arguably one of the most intimate things we will ever know. But the comfort of our own physical boundaries can be altered in various ways. In this analysis, we will look at how vision contributes to the sense of owning a body by analysing six abnormal conditions: the rubber hand illusion, phantom limbs, somatoparaphrenia, the body-swap illusion, out-of-body experiences, and heautoscopy. Examinations of these experimental or pathological conditions has granted a greater understanding of body-ownership. It was discovered that vision plays different modulatory roles, being more intricately involved in full-body ownership than in part-body ownership. Vision appears to be highly connected to self-location and first-person perspective, which both are contributing factors in projecting the sense of ownership to an external location. In part-body ownership, however, vision can be overruled by other senses, such as proprioception. Though it is still able to contribute to the illusion of projecting ownership and proprioceptive displacement to a rubber hand.
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Svedberg, Jonnie Juhani. "Reality Check : A review of design principles within emergent XR artefacts." Thesis, Umeå universitet, Institutionen för informatik, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-175019.
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With the advent of novel digital interfaces such as augmented, mixed and virtual reality, the way we interact with digital artefacts is changing at a nearly reckless pace. The adoption rate within enterprise applications is racing, with mass adoption among consumers soon to follow. This paper aims to iterate a key question sometimes hidden within these rapid developments; are the practices used to develop these artefacts properly tested and evaluated as the best possible ones? In order to answer this, we will explore and evaluate how existing best practices adhere to empirical evidence, but also to experiment with potential avenues of alternative design methodologies. Once adequate conclusions are reached, they will be utilized to design a prototype/proof of concept to showcase just how aninterface/interaction made with the new considerations in mind can differ from those made with contemporary design principles. Upon evaluation of thi sexperimental prototype which utilized the user’s hands as physical, tactile feedback for interactions, respondents were overall positive to this method of interaction, despite some discomfort from the limitations imposed by this specific technical approach. Due to this, it is strongly suggested that development of XR artefacts might often be designed around these technical limitations instead of a truly best practice. This is why we heavily implore both further testing and experimentation as time goes on, since emergent technologies might lack these limitations and therefore enable richer, better interaction methods and experiences within XR.
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Boukricha, Hana [Verfasser]. "Simulating empathy in virtual humans / Hana Boukricha." Bielefeld : Universitätsbibliothek Bielefeld, 2013. http://d-nb.info/1038526078/34.
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Slavkoff, Evgeny. "Articulating human hands and manipulating objects in virtual environments." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp01/MQ37284.pdf.
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Slavkoff, Evgeny. "Articulating human hands and manipulating objects in virtual environments." Thesis, McGill University, 1996. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=37521.
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This thesis research addresses the problem of human representation in virtual environments (VE). Previous work done on Virtual Reality (ESOPE-RV) lacks an interface to produce dynamic, real-time interactive simulated human representation.The goal of this research was to create the McGill Virtual Operator as a stand alone, independent software application interfacing the Human Operator with various synthetic worlds. For the lower body, including the feet we use pedals to perform the navigation in VE giving a locomotive motion which is simple and acceptable. However, the upper body motion and especially the human hand articulation is much more complex because humans interact with the environment largely with their hands. The approach taken in this thesis is to develop an interactive interface which achieves dynamic real-time hand manipulation while not encumbering the user.
The interface is based on two inexpensive data gloves and commercially available six degree of freedom sonar sensor technology and various routines and kinematics algorithms. The result of this work is the creation of a human body interface focused on hand manipulation as a McGill Virtual Operator which can be incorporated for use in any large-scale interactive VE. Ultrasonic sensors are strapped onto each arm of the user, to read their position and orientation. The motion of the fingers is recorded by the data gloves and the information is transmitted to software, which in turn replicates the same motion of the computer human hands in real-time. Experiments were carried out using a collection of fourteen tools designed for the WITS training environment. The performance results of these interactive extensions to the VR environment was evaluated and found to be satisfactory. (Abstract shortened by UMI.)
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Embry, Bruce A. "Finding alternatives to the hard disk drive for virtual memory /." Diss., CLICK HERE for online access, 2009. http://contentdm.lib.byu.edu/ETD/image/etd2985.pdf.
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Embry, Bruce Albert. "Finding Alternatives to the Hard Disk Drive for Virtual Memory." BYU ScholarsArchive, 2009. https://scholarsarchive.byu.edu/etd/1727.
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Current computer systems fill the demand of operating systems and applications for ever greater amounts of random access memory by paging the least recently used data to the hard disk drive. This paging process is called "virtual memory," to indicate that the hard disk drive is used to create the illusion that the computer has more random access memory than it actually has. Unfortunately, the fastest hard disk drives are over five orders of magnitude slower than the DRAM they are emulating. When the demand for memory increases to the point that processes are being continually saved to disk and then retrieved again, a process called "thrashing" occurs, and the performance of the entire computer system plummets. This thesis sought to find alternatives for home and small business computer users to the hard disk drive for virtual memory which would not suffer from the same long delays. Virtual memory is especially important for older computers, which often are limited by their motherboards, their processors and their power supplies to a relatively small amount of random access memory. Thus, this thesis was focused on improving the performance of older computers by replacing the hard disk drive with faster technologies for the virtual memory. Of the different technologies considered, flash memory was selected because of its low power requirements, its ready availability, its relatively low cost and its significantly faster random access times. Two devices were evaluated on a system with a 512MB of RAM, a Pentium 4 processor and a SATA hard disk drive. Theoretical models and a simulator were developed, and physical performance measurements were taken. Flash memory was not shown to be significantly faster than the hard disk drive in virtual memory applications.
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Nordin, Johan. "Realistic virtual hands: Exploring how appearance affects the sense of embodiment." Thesis, Linköpings universitet, Medie- och Informationsteknik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-137672.
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How would you react if you looked down on your hands and they had been replaced with someone else’s hands? This is the case for virtual reality applications that incorporate virtual hands, all applications have their own representation of virtual hands but none takes the user’s own hand into account. For this reason, we have created a framework that allows to customize geometric features of existing hand models towards a more personal hand representation. We have designed and conducted an experiment to study sense of ownership of four virtual hand representations. It was found that participants pay attention to size of the hand and the length of the fingers but do not necessarily consider the virtual hands as their own. We believe that a virtual hand that truly creates the impression of one’s own hand may benefit educational, training or rehabilitation virtual reality applications. In order to achieve this, our conclusion is that a certain extent of size, shape and appearance of the user’s hand need to be considered.
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Croom, John R. III. "Knowledge Retention for Computer Simulations| A study comparing virtual and hands-on laboratories." Thesis, Wilkes University, 2014. http://pqdtopen.proquest.com/#viewpdf?dispub=3630293.
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The use of virtual laboratories has the potential to change physics education. These low-cost, interactive computer activities interest students, allow for easy setup, and give educators a way to teach laboratory based online classes. This study investigated whether virtual laboratories could replace traditional hands-on laboratories and whether students could retain the same long-term knowledge in virtual laboratories as compared to hands-on laboratories. This study is a quantitative quasi-experiment that used a multiple posttest design to determine if students using virtual laboratories would retain the same knowledge as students who performed hands-on laboratories after 9 weeks. The study was composed of 336 students from 14 school districts. Students had their performances on the laboratories and their retention of the laboratories compared to a series of factors that might have affected their retention using a pretest and two posttests, which were compared using a t test. The results showed no significant difference in short-term learning between the hands-on laboratory groups and virtual laboratory groups. There was, however, a significant difference (p = .005) between the groups in long-term retention; students in the hands-on laboratory groups retained more information than those in the virtual laboratory groups. These results suggest that long-term learning is enhanced when a laboratory contains a hands-on component. Finally, the results showed that both groups of students felt their particular laboratory style was superior to the alternative method. The findings of this study can be used to improve the integration of virtual laboratories into science curriculum.
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Licona, Rodriguez Angel Ricardo. "Collaborative hands-on training on haptic simulators." Thesis, Lyon, 2020. http://www.theses.fr/2020LYSEI018.
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Depuis les débuts de la médecine, les étudiants en médecine s’entraînent sur des simulateurs (animaux, cadavres, mannequins) afin d’acquérir puis enrichir leurs compétences médicales, dont notamment celles nécessitant des gestes précis. C’est un moyen de faire des erreurs sans blesser de patient. Pourtant, ces simulateurs manquent souvent de réalisme, s’usent et finissent par coûter cher sur le long terme. Depuis plusieurs décennies, les technologies de simulation informatique ont enrichi le panel des simulateurs médicaux, et aujourd’hui les technologies haptiques offrent désormais un réalisme encore accru. Cependant, ces simulateurs haptiques n’intègrent pas le formateur dans la simulation, ce qui empêche de former les apprenant sur des gestes impliquant à la fois des trajectoires et des interactions outil/environnement où les efforts doivent être subtilement dosés et donc maîtrisés. Dans les travaux de recherche récents, des architectures dual-user (à deux utilisateurs) de simulateurs dédiés à la formation au geste ont été proposés ces dernières années, mais l’étude bibliographique proposée dans ce document démontre qu’aucun d’entre eux n’a été conçu dans ce sens : un retour haptique est proposé à l’apprenant mais le formateur n’a pas la possibilité de montrer simultanément la position des outils et les efforts à appliquer dessus. Récemment M. Fei Liu a conçu une solution à ce besoin (l’architecture dual-user ESC - Energy Shared Control), fondée sur une approche énergétique garantissant la passivité et donc la stabilité du), utilisable avec un dispositif esclave réel ou virtuel, et intégrant un mécanisme d’autorité adaptative (Adaptive Authority Adjustment - AAA) permettant au formateur de reprendre la main instantanément à partir du moment où l’apprenant dévie de la trajectoire désirée par le formateur. Cependant, cette solution se limitait à un seul degré de liberté et ce mécanisme d’autorité adaptative nécessitait de régler laborieusement trois paramètres peu intuitifs. Les solutions proposées dans ce mémoire poursuivent donc les travaux de M. Liu en améliorant l’architecture ESC afin de l’étendre à des dispositifs à plusieurs degrés de liberté, ayant potentiellement des cinématiques différentes (surtout le dispositif esclave par rapport aux dispositifs maîtres) et à plusieurs apprenants simultanés. Une amélioration de la fonction AAA est proposée ainsi que des profils d’utilisation dépendant du niveau de l’apprenant. Une première série de retours d’usage a été réalisée afin de déterminer l’intérêt pédagogique de cette fonction. Les résultats ne permettant pas de conclure, des préconisations sont proposées pour une deuxième sérieMedical students can use training simulators to improve their skills in a faster way using advanced tools that could give them quantitative feedback about their performance. Nowadays there are some haptic simulators used in several areas of medical education. However, most of these simulators can be used by only one user at the time, with no possible ways to perform guided training. Besides, these simulators lack an internal architecture that allows them to be expanded into multiple users or multiple devices. Expanding these simulators to a multi-user system can lead to parallel teaching. To develop a multi-user haptic simulator, it is necessary to establish an architecture that offers stability, position tracking and haptic force feedback for each involved device. The trainer and trainees will be able to manipulate the slave (either a real robot handling a surgical tool or a numeric simulation) system using their proper Master haptic devices to perform the surgical task. The architecture must offer an authority-sharing mechanism that ensures the dominance of allowed users during the training and a proper estimation of the slave’s environment forces fed back to for each user. The following thesis shows the results obtained with the implementation of a previously proposed architecture, expansion it into n-DoF (in angular and cartesian workspace) and that can be used with devices that do not share the same kinematic configuration. The new architecture also allows implementing m-trainee consoles to expand the number of users that can learn from an experienced trainer at the same time. The expansion of the system, evaluation of transparency and results obtained for free motion and contact cases are shown. A new adaptative dominance function is also proposed that present some advantages over the ones proposed in the bibliography. The results of a study of how much this function aids trainees in the learning process is also detailed with the used test bank and a proposed protocol. Finally, its detailed future work that can be done to improve the architecture as well the necessaries studies that will probe its functionality
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Powell, Jaemin. "Hardware design for an electro-mechanical bicycle simulator in an immersive virtual reality environment." Thesis, University of Iowa, 2017. https://ir.uiowa.edu/etd/5981.
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Roughly 50,000 people are injured in bicycle collisions with motor vehicles each year. The Hank Bicycle Simulator provides a virtual environment to study and reduce this tragic loss by safely investigating the interaction of bicycle riders and traffic, particularly for bicyclists crossing streets. The bicycle simulator design focuses on the bicycle and rider inertia, the predominant dynamic element for riders moving from a stopped position. The Hank Bicycle Simulator’s flywheel provides instantaneous inertial response while a servomotor provides simulated wind resistance to pedaling. This work describes the simulator design and a validation experiment that compares the simulator performance to theoretical predictions. The Hank Bicycle Simulator achieved initial acceleration with less than 0.20% error at realistic rider weights. The observed terminal velocity achieved less than 3.75%, with smaller errors for heavier riders. This allows the rider to cross a street with about a 60 ms time difference between the simulator and a real-life rider pedaling at a constant propulsive force. The Hank Bicycle Simulator was also validated through various physical experiments measuring the system inertia, the time delay of the electrical components, and the overall system performance. Such careful system validation for a mechanical feedback system is relatively rare in simulation research and is unique among previous reports of bicycle simulators.
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Blackmon, Ferrol R. "Virtual Dynamic Tunnel: A Target-Agnostic Assistive User Interface Algorithm for Head-Operated Input Devices." Digital Archive @ GSU, 2010. http://digitalarchive.gsu.edu/cs_diss/58.
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Today the effective use of computers (e.g. those with Internet browsers and graphical interfaces) involves the use of some sort of cursor control like what a mouse provides. However, a standard mouse is not always the best option for all users. There are currently many devices available to provide alternative computer access. These devices may be divided into categories: brain-computer interfaces (BCI), mouth-based controls, camera-based controls, and head-tilt controls. There is no single solution as each device and application has to be tailored to each user's unique preferences and abilities. Furthermore, each device category has certain strengths and weaknesses that need to be considered when making an effective match between a user and a device. One problem that remains is that these alternative input devices do not perform as well when compared to standard mouse devices. To help with this, assistive user interface techniques can be employed. While research shows that these techniques help, most require that modifications be made to the user interfaces or that a user's intended target be known beforehand by the host computer. In this research, a novel target-agnostic assistive user interface algorithm intended to improve usage performance for both head-operated and standard mouse devices is designed, implemented (as a mouse device driver and in host computer software) and experimentally evaluated. In addition, a new wireless head-operated input device requiring no special host computer hardware, is designed, built and evaluated. It was found that the Virtual Dynamic Tunnel algorithm improved performance for a standard mouse in straight tunnel trials and that nearly 60% of users would be willing to use the head-tilt mouse as a hands-free option for cursor control.
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Dlamini, Mongi. "Measurement of Hard Exclusive Electroproduction of Neutral Meson Cross Section in Hall A of JLab with CEBAF at 12 GeV." Ohio University / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1538133026665123.
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Hungr, Nikolai Anthony. "Haptic emulation of hard surfaces with applications to orthopaedic surgery." Thesis, University of British Columbia, 2008. http://hdl.handle.net/2429/639.
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A generally accepted goal in orthopaedic surgery today is to maximize conservation of tissue and reduce tissue damage. Bone-conserving implants have bone-mating surfaces that reproduce the natural curvature of bone structures, requiring less bone removal. No small, reliable, inexpensive and universal bone sculpting technique currently exists, however, that can both create and accurately align such complex surfaces. The goal of this thesis was to develop a haptic hard surface emulation mechanism that could be applied to curvilinear bone sculpting using a surgical robot. A novel dynamic physical constraint concept was developed that is able to emulate realistic hard constraints, smooth surface following, and realistic surface rigidity, while allowing complete freedom of motion away from the constraints. The concept was verified through the construction of a two-link manipulator prototype. Tests were run on nine users that involved each user tracing out five different virtual surfaces on a drawing surface using the prototype. The primary purposes of prototype testing were to obtain subjective data on how effectively the dynamic physical constraint concept simulates simple surfaces, to assess how it reacts to typical user interactions and to identify any unexpected behaviour. Users were 100% satisfied with the prototype’s ability to emulate realistic and stiff hard surfaces and with its ease of manipulation. The amount of incursion into each of the virtual surfaces by all the users was measured to assess the precision of the system with the goal of deciding whether this new haptic concept should be further developed specifically for precision applications such as surgery. For curvilinear surfaces, 90% of the cumulative distribution of the measured data was less than 2mm, while for linear surfaces it was less than 6mm. Four behavioural effects were noticed: lateral deflection, reverse ‘stickiness’, hysteresis and instability in certain areas. These effects were studied in detail to determine how to either eliminate them or to minimize them through system design optimization. A computer simulation was also used to model the behaviour of the prototype and to gain further understanding of these effects. These analyses showed that the concept can be successfully used in curvilinear bone sculpting.
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Kent, Leanne E. "Tragic Dilemmas, Virtue Ethics and Moral Luck." Bowling Green State University / OhioLINK, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1225468182.
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Landers, Kathy Michelle. "Using Simulations to Prepare for College and Careers in Information Technology." ScholarWorks, 2019. https://scholarworks.waldenu.edu/dissertations/7549.
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While simulators can be used in place of hands-on hardware, there was not a significant body of quantitative research supporting the use of simulators for college and career success at the secondary level in information technology (IT). The purpose of this quantitative, nonexperimental study was to determine if there was a significant difference in college and career readiness of New York state high school students in approved IT content cluster high school programs, between those who use simulations and those who use hands-on hardware. Kolb's theory of experiential learning was the theoretical foundation for this research. The research questions examined whether there was a significant difference in the written exam grades, the hands-on exam grades, and the certification pass rates of students, based on the percentage of simulation used in their coursework. A survey was used to collect data on 60 students. A one-way Welch ANOVA indicated no significant difference in written grades between groups. A Kruskal-Wallis ANOVA showed statistical significance between groups using all simulated labs and less than 50% simulated labs, as well as between all simulated labs and 50% or greater simulated labs for hands-on grades. Fisher's Exact Test indicated that the proportion of students in the less than 50% simulated labs group who earned industry-level certifications was statistically significantly higher than the 50% or greater simulated labs group or the all simulated labs group. Implications for social change are that workers with entry-level IT skills can fill jobs in the growing IT field that offers well-paying jobs with more promising futures.
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Westerteiger, Rolf [Verfasser], Hans [Akademischer Betreuer] Hagen, Bernd [Akademischer Betreuer] Hamann, and Christoph [Akademischer Betreuer] Garth. "Virtual Reality Methods for Research in the Geosciences / Rolf Westerteiger. Betreuer: Hans Hagen ; Bernd Hamann ; Christoph Garth." Kaiserslautern : Technische Universität Kaiserslautern, 2014. http://d-nb.info/106393379X/34.
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KOLARIC, SINISA. "TOWARDS DIRECT SPATIAL MANIPULATION OF VIRTUAL 3D OBJECTS USING VISUAL TRACKING AND GESTURE RECOGNITION OF UNMARKED HANDS." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2008. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=12443@1.
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A necessidade de executar manipulações espaciais (como
seleção, deslocamento, rotação, e escalamento) de objetos
virtuais 3D é comum a muitos tipos de aplicações do
software, inclusive aplicações de computer-aided design
(CAD), computer-aided modeling (CAM) e aplicações de
visualização científica e de engenharia. Neste trabalho é
apresentado um protótipo de aplicação para manipulação de
objetos virtuais 3D utilizando movimentos livres de mãos e
sem o uso de marcadores, podendo-se fazer gestos com uma ou
duas mãos. O usuário move as mãos no volume de trabalho
situado imediatamente acima da mesa, e o sistema integra
ambas as mãos (seus centróides) no ambiente virtual que
corresponde a este volume de trabalho. As mãos são
detectadas e seus gestos reconhecidos usando o método
de detecção de Viola-Jones. Tal reconhecimento de gestos é
assim usado para ligar e desligar modalidades da
manipulação. O rastreamento 3D de até duas mãos é então
obtido por uma combinação de rastreamento 2D chamado flocks-
of-KLT-features e reconstrução 3D baseada em triangulação
estéreo.The need to perform spatial manipulations (like selection, translation, rotation, and scaling) of virtual 3D objects is common to many types of software applications, including computer-aided design (CAD), computer-aided modeling (CAM) and scientific and engineering visualization applications. In this work, a prototype application for manipulation of 3D virtual objects using free-hand 3D movements of bare (that is, unmarked, uninstrumented) hands, as well as using one-handed and two-handed manipulation gestures, is demonstrated. The user moves his hands in the work volume situated immediately above the desktop, and the system effectively integrates both hands (their centroids) into the virtual environment corresponding to this work volume. The hands are being detected and their posture recognized using the Viola-Jones detection method, and the hand posture recognition thus obtained is then used for switching between manipulation modes. Full 3D tracking of up to two hands is obtained by a combination of 2D flocksof-KLT-features tracking and 3D reconstruction based on stereo riangulation.