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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
391

Realization of a serially-linked haptic device / Framtagning av en serielänkad haptisk enhet

Massoumzadeh, Ramtin January 2017 (has links)
Spatial haptic interfaces have existed for more than 20 years but have not been widespread despite promising applications. The few devices found in the market as of today are either considered costly, of higher quality and produced in smaller series or mass-produced and cheap, but of lower quality. This thesis aims to develop a new serially-linked everyday haptic desktop product under the project name Polhem. It aims to be based on the previous efforts of WoodenHaptics and AluHaptics, developed by Forsslund et al. The electronics and control software is shared between the WoodenHaptics, the AluHaptics as well as the Polhem designed and manufactured in this project. Polhem is capable of delivering forces in 3 DOF and its manipulandum is trackable in 6 DOF. Polhem is designed so as to eliminate problems related to angular tracking technologies currently used in some higher-end haptic devices. / Spatiala haptiska gränssnitt har existerat i mer än 20 år men har trots sina lovande applikationer inte varit tillgänglig i någon större utsträckning. De få enheter som finns på marknaden i dagsläget anses antingen vara dyra, av högre kvalitet och produceras i mindre serier eller massproducerade och billiga, men av lägre kvalitet. Denna avhandling syftar till att utveckla en ny serielänkad haptisk produkt under projektnamnet Polhem. Polhem syftar till att baseras på de föregående enheterna WoodenHaptics och AluHaptics, som utvecklats av Forsslund et al. Elektroniken och reglermjukvaran delas mellan WoodenHaptics, AluHaptics och Polhem. Polhem kan leverera krafter i 3 frihetsgrader och dess manipulandum kan spåras i 6 frihetsgrader. Polhem är utformad så att den eliminerar problem relaterade till äldre vinkelspårningsteknologi som för närvarande används i många högpresterande haptiska enheter
392

Exploring the effect of using vibrate-type haptic glove in the VR industrial training task

Hsu, Yi-Hsiou January 2020 (has links)
Is it a dream came true for you to experience a Virtual Reality (VR) and be able to touch virtual objects and manipulate them with your bare hands? The recent growth of the Virtual Reality market resulted in an intensification of the development of the haptics gloves technology. The newly haptics gloves, Bebop gloves launched and commercialized recently which will use for this study. Earlier research has explored a range of haptics effects mainly on VR surgery or gaming. Yet, VR industrial training has gradually received attention in recent years. Creating multiple scenarios in the virtual scene is not only cost-effective but also increases safety and reduces training time. However, not many research studies have explored using haptic gloves in the VR industrial training environment. This study tries to complement earlier research by investigating usability and user performance using bebop vibration gloves in VR industrial training. The purposes were to provide a usability review of bebop gloves and explored the effect of haptics in VR industrial training. Three different haptics settings (Non-haptics, Partial haptics, and Full-haptics) were being set up. Eighteen users were then recruited to try randomly two haptics settings. Each user had to complete a five steps VR industrial training task while “thinking aloud”, followed by questionnaires and interviews after the task. The error and time recorded for each training step. These results confirmed several conclusions drawn in earlier research about how the haptics affect user performance in the VR environment, as well as how the behavior changes when using the haptics gloves in a VR environment. Last but not least the results also pointed to the importance of vibration haptics benefits in small-scale actions and provide the user with an interpersonal confirmation. / Är det en dröm som förverkligades för dig att uppleva en virtuell verklighet (VR) och kunna röra virtuella objekt och manipulera dem med bara händer? Den senaste tillväxten av marknaden för Virtual Reality resulterade i en intensifiering av utvecklingen av haptikhandskar-tekniken. De nyligen haptiska handskarna, Bebophandskar lanserade och kommersialiserades nyligen som kommer att användas för denna studie. Tidigare forskning har undersökt en rad haptiska effekter främst på VR-kirurgi eller spel. Ändå har VR-industriell utbildning gradvis fått uppmärksamhet under de senaste åren. Att skapa flera scenarier i den virtuella scenen är inte bara kostnadseffektivt utan ökar också säkerheten och minskar tiden. Men inte många forskningsstudier har undersökt användning av haptiska handskar i VR: s industriella utbildningsmiljö. Denna studie försöker komplettera tidigare forskning genom att undersöka användbarhet och användarprestanda med hjälp av bebop-vibrationshandskar i VR-industriutbildning. Syftena var att tillhandahålla en användbarhetsgranskning av bebop-handskar och utforska effekten av haptik i VR-industriutbildningen. Tre olika haptikinställningar (Non-haptics, Partial haptics och Full-haptics) inställdes. Atten användare rekryterades sedan för att testa slumpmässigt två haptikinställningar. Varje användare måste genomföra en femstegs VR-industriell träningsuppgift medan han ”tänker högt”, följt av frågeformulär och intervjuer efter uppgiften. Felet och tiden som registrerats för varje träningssteg. Dessa resultat bekräftade flera slutsatser som dragits i tidigare forskning om hur haptiken påverkar användarnas prestanda i VR-miljön, liksom hur beteendet förändras när man använder haptikhandskarna i en VR-miljö. Sist men inte minst pekade resultaten också på vikten av fördelar med vibrationshaptik i småskaliga åtgärder och ger användaren en interpersonell bekräftelse.
393

Design and control of a three degree-of-freedom planar parallel robot

Joshi, Atul Ravindra January 2003 (has links)
No description available.
394

Control Implementation and Co-simulation  of A 6-DOF TAU Haptic Device / Reglering, implementering och samsimulering av en 6-DOF TAU haptisk enhet

Zhang, Yang January 2020 (has links)
In the research area of virtual reality, the term haptic rendering is defined as the process of computing and generating the interaction force between the virtual object and the operator. One of the major challenges of haptic rendering is the stably rendering contact with a stiff object. Traditional haptic rendering algorithms performs well when rendering contact with soft objects. But when it is used to simulate contact with objects with high stiffness, the algorithm may cause unstable response of haptic devices. Such unstable behavior (e.g., oscillation of the device) can destroy the fidelity of the virtual environment and even hurt the user.  To address the above stability issues, a new design approach has been proposed in this paper. The proposed approach consists of three main process steps: modeling and linearization in ADAMS, LQR position controller design, verification with co-simulation. In the first step, a simulation model of the system is firstly created in ADAMS/View. Then this nonlinear ADAMS multi-body dynamics model is linearized and exported as a set of linear state space matrices with the help of ADAMS/Linear. In the second step, different from the traditional force-control algorithms, LQR position controller is developed in Matlab Simulink based on the exported matrices to emulate interactions with stiff objects. At last, the verification of control performance is carried out by setting up co-simulation between ADAMS and Simulink.  A case study implementation of this proposed method was performed on the TAU device which was previously developed by Machine Design department at KTH. TAU is an asymmetrical parallel robot with six degrees of freedom for the simulation of surgical procedures like drilling and milling of hard tissues of bones and teeth. The results show that the linear model exported from ADAMS is sufficiently accurate and the proposed controller can render a virtual wall with stiffness at the level of 105 N/m. / Inom forskningsområdet virtuell verklighet definieras termen hatisk återgivning (haptic rendering) som processen för beräkning och generering av interaktiva krafter mellan det virtuella objektet och användaren. En av de största utmaningarna med haptisk återgivning är att stabilt simulera känslan av beröring av styv material för användare. Traditionella algoritmer fungerar när det gäller att simulera känslan av beröring av mjuk material, men när algoritmerna används för att simulera kontakt med materialer med stor styvhet kan det orsaka instabilitet hos haptiska enheter. Sådana instabilitet, bland annat svängning hos enheten, kan förstöra den virtuella miljöns exakthet och till och med skada användare.  Denna uppsats försöker ta itu med det ovanstående problemet genom att föreslå en ny designmetod. Metoden består av tre huvudsteg: modellering och linearisering med hjälp av ADAMS, design av LQR-positionskontroll, och verifiering med samsimulering (co-simulation). I det första steget skapas systemets simuleringsmodell med hjälp av ADAMS/View. Sedan linjäriseras denna icke-linjära ADAMS-multikroppsdynamikmodell. Modellen exporteras som linjära tillståndsmatriser med hjälp av ADAMS/Linear. I det andra steget designas en LQR-positionskontroll med hjälp av Matlab Simulink baserat på de exporterade matriserna tidigare för att simulera interaktioner med styv material, vilket skiljer sig från de traditionella kraftkontrollalgoritmer (force-control algorithms). I det sista steget utförs verifieringen av positionskontrollens prestanda genom att ställa in samsimulering (co-simulation) mellan ADAMS och Simulink.  En testkörning av denna föreslagna metod har utförs på TAU-enheten som tidigare utvecklades av KTH institutionen för maskinkonstruktion. TAU är en asymmetrisk parallellsrobot med sex frihetsgrader för att simulera kirurgiska ingrepp som borrning av hårda vävnader i ben och tänder. Resultaten visar att den linjära modellen som exporteras från ADAMS är tillräckligt korrekt, för den föreslagna positionskontrollen kan framställa en virtuell vägg med styvhet vid 105 N/m.
395

TOWARDS IMPROVING TELETACTION IN TELEOPERATION TASKS USING VISION-BASED TACTILE SENSORS

Oscar Jia Jun Yu (18391263) 01 May 2024 (has links)
<p dir="ltr">Teletaction, the transmission of tactile feedback or touch, is a crucial aspect in the</p><p dir="ltr">field of teleoperation. High-quality teletaction feedback allows users to remotely manipulate</p><p dir="ltr">objects and increase the quality of the human-machine interface between the operator and</p><p dir="ltr">the robot, making complex manipulation tasks possible. Advances in the field of teletaction</p><p dir="ltr">for teleoperation however, have yet to make full use of the high-resolution 3D data provided</p><p dir="ltr">by modern vision-based tactile sensors. Existing solutions for teletaction lack in one or more</p><p dir="ltr">areas of form or function, such as fidelity or hardware footprint. In this thesis, we showcase</p><p dir="ltr">our research into a low-cost teletaction device for teleoperation that can utilize the real-time</p><p dir="ltr">high-resolution tactile information from vision-based tactile sensors, through both physical</p><p dir="ltr">3D surface reconstruction and shear displacement. We present our device, the Feelit, which</p><p dir="ltr">uses a combination of a pin-based shape display and compliant mechanisms to accomplish</p><p dir="ltr">this task. The pin-based shape display utilizes an array of 24 servomotors with miniature</p><p dir="ltr">Bowden cables, giving the device a resolution of 6x4 pins in a 15x10 mm display footprint.</p><p dir="ltr">Each pin can actuate up to 3 mm in 200 ms, while providing 80 N of force and 3 um of</p><p dir="ltr">depth resolution. Shear displacement and rotation is achieved using a compliant mechanism</p><p dir="ltr">design, allowing a minimum of 1 mm displacement laterally and 10 degrees of rotation. This</p><p dir="ltr">real-time 3D tactile reconstruction is achieved with the use of a vision-based tactile sensor,</p><p dir="ltr">the GelSight, along with an algorithm that samples the depth data and marker tracking to</p><p dir="ltr">generate actuator commands. With our device we perform a series of experiments including</p><p dir="ltr">shape recognition and relative weight identification, showing that our device has the potential</p><p dir="ltr">to expand teletaction capabilities in the teleoperation space.</p>
396

The Sensory and Haptic Nature of Art Therapy Materials With Young Children Ages 0-5yrs Old of Complex Trauma

Duncan, Sarah 01 April 2019 (has links) (PDF)
This survey study with an art response aims to further understand how the sensory and haptic nature of art therapy materials can aid in healing within the therapeutic process. Specifically, it will explore young children, ages 0-5yrs old, of complex trauma and how they respond to art materials within the therapeutic process. Surveys were distributed to mental health therapists working with the 0-5 year old population in order to gather baseline information about how young children who have experienced trauma, respond to methods of interventions, including art materials. Through analysis of the participants’ survey responses and artwork, emergent themes revealed insight for further research and reinforced the importance of a consistent, nurturing caregiving relationship. These findings and themes illuminated the importance of relationship and revealed inquiries about the sensory and haptic nature of art materials being utilized for assessment in dyadic therapy with children 0-5 years old.
397

Trans Cinema and Its Exit Scapes : A Transfeminist Reading of Utopian Sensibility and Gender Dissidence in Contemporary Film

Straube, Wibke January 2014 (has links)
Trans Cinema and its Exit Scapes offers a critical and creative intervention into cultural representations of gendered body dissidence in contemporary film. The study argues for the possibility of finding spaces of “disidentification”, so-called “exit scapes” within the films. Exit scapes disrupt the dominant cinematic regime set up for the trans character, which ties them into stories of discrimination, humiliation and violence. In Trans Cinema, for instance films such as Hedwig and the Angry Inch (2001), Transamerica (2005), Romeos (2011) and Laurence Anyways (2012), scenes of singing, dancing and dreaming allow a different form of engagement with the films. As argued here, they allow a critical re-reading and an affirmative re-imagining of trans embodiment. The aim of this study is to investigate the utopian and hopeful potential within Trans Cinema from a critical transfeminist perspective. While focusing in particular on trans entrants as “spectators” or readers, this study draws on the work of a wide range of feminist and cultural scholars, such as Sara Ahmed, Susan Stryker, José Esteban Muñoz, Trinh T. Minh-Ha, Karen Barad and Donna Haraway. The thesis etches out cinematic spatiotemporalities that unfold possibilities of utopian worlding and trans becoming through a set of conceptual innovations. By utilising a critical approach to audio-visuality and feminist film theory, the thesis re-conceptualises haptic spectatorship theory and its critique in western modernist ocularcentricism through a set of conceptual innovations. The methodological tools developed in this thesis, such as the “entrant”, the “exit scape” and “sensible cinematic intra-activity”, feature here as a multisensorial methodology for transdisciplinary transgender studies and feminist film theory as well as visual culture at large. / Trans Cinema and its Exit Scapes är en kritisk och kreativ intervention med fokus på kulturella representationer av kroppar som bryter mot en könsbinär ordning i samtida film. Studien argumenterar för möjligheten att hitta utrymmen för “disidentification”, så kallade “exit scapes” inom filmerna. Exit scapes stör den dominanta filmiska ordning som skapats för transkaraktären, en ordning som är förbunden med berättelser om diskriminering, förödmjukelse och våld. Inom Trans Cinema, i filmer som exempelvis Hedwig and the Angry Inch (2001), Transamerica (2005), Romeos (2011) and Laurence Anyways (2012), öppnar scener med sång, dans och drömmar upp för andra former av engagemang med filmerna. Som det argumenteras för i avhandlingen tillåter dessa ett kritiskt omformulerande av, och ett nytt affirmativt sätt att föreställa sig, transkroppslighet. Syftet med den här studien är att undersöka den utopiska och hoppfulla potential som finns inom transfilm utifrån ett kritiskt transfeministiskt perspektiv. Även om studien främst riktar sig till trans entrants som “åskådare” eller läsare, så har den en bred teoretisk bas hämtad från verk av en lång rad feministiska forskare inom kulturfältet, såsom Sara Ahmed, Susan Stryker, José Esteban Muñoz, Trinh T. Minh-Ha, Karen Barad och Donna Haraway. Denna avhandling skissar filmiska spatiotemporaliteter, vilka öppnar för möjligheter av utopiska värdsliga och transsubjektiva tillblivelser genom utvecklandet av olika teoretiska begrepp. Genom ett kritiskt förhållningssätt till audiovisualitet och feministisk filmteori, revideras och omformuleras haptisk åskådarskapsteori och dess kritik i en västerländsk okularcentrism genom olika teoretiska innovationer. De metodologiska verktygen som utvecklas i avhandlingen, såsom “the entrant”, “the exit scape” samt “sensible cinematic intra-activity” utgör här funktionen som multisensorisk metodologi för transdisciplinära transstudier, feministisk filmteori samt för visuell kultur i stort.
398

Touching the Essence of Life : Haptic Virtual Proteins for Learning

Bivall, Petter January 2010 (has links)
This dissertation presents research in the development and use of a multi-modal visual and haptic virtual model in higher education. The model, named Chemical Force Feedback (CFF), represents molecular recognition through the example of protein-ligand docking, and enables students to simultaneously see and feel representations of the protein and ligand molecules and their force interactions. The research efforts have been divided between educational research aspects and development of haptic feedback techniques. The CFF model was evaluated in situ through multiple data-collections in a university course on molecular interactions. To isolate possible influences of haptics on learning, half of the students ran CFF with haptics, and the others used the equipment with force feedback disabled. Pre- and post-tests showed a significant learning gain for all students. A particular influence of haptics was found on students reasoning, discovered through an open-ended written probe where students' responses contained elaborate descriptions of the molecular recognition process. Students' interactions with the system were analyzed using customized information visualization tools. Analysis revealed differences between the groups, for example, in their use of visual representations on offer, and in how they moved the ligand molecule. Differences in representational and interactive behaviours showed relationships with aspects of the learning outcomes. The CFF model was improved in an iterative evaluation and development process. A focus was placed on force model design, where one significant challenge was in conveying information from data with large force differences, ranging from very weak interactions to extreme forces generated when atoms collide. Therefore, a History Dependent Transfer Function (HDTF) was designed which adapts the translation of forces derived from the data to output forces according to the properties of the recently derived forces. Evaluation revealed that the HDTF improves the ability to haptically detect features in volumetric data with large force ranges. To further enable force models with high fidelity, an investigation was conducted to determine the perceptual Just Noticeable Difference (JND) in force for detection of interfaces between features in volumetric data. Results showed that JNDs vary depending on the magnitude of the forces in the volume and depending on where in the workspace the data is presented.
399

Trans Cinema and Its Exit Scapes : A Transfeminist Reading of Utopian Sensibility and Gender Dissidence in Contemporary Film

Straube, Wibke January 2014 (has links)
Trans Cinema and its Exit Scapes offers a critical and creative intervention into cultural representations of gendered body dissidence in contemporary film. The study argues for the possibility of finding spaces of “disidentification”, so-called “exit scapes” within the films. Exit scapes disrupt the dominant cinematic regime set up for the trans character, which ties them into stories of discrimination, humiliation and violence. In Trans Cinema, for instance films such as Hedwig and the Angry Inch (2001), Transamerica (2005), Romeos (2011) and Laurence Anyways (2012), scenes of singing, dancing and dreaming allow a different form of engagement with the films. As argued here, they allow a critical re-reading and an affirmative re-imagining of trans embodiment. The aim of this study is to investigate the utopian and hopeful potential within Trans Cinema from a critical transfeminist perspective. While focusing in particular on trans entrants as “spectators” or readers, this study draws on the work of a wide range of feminist and cultural scholars, such as Sara Ahmed, Susan Stryker, José Esteban Muñoz, Trinh T. Minh-Ha, Karen Barad and Donna Haraway. The thesis etches out cinematic spatiotemporalities that unfold possibilities of utopian worlding and trans becoming through a set of conceptual innovations. By utilising a critical approach to audio-visuality and feminist film theory, the thesis re-conceptualises haptic spectatorship theory and its critique in western modernist ocularcentricism through a set of conceptual innovations. The methodological tools developed in this thesis, such as the “entrant”, the “exit scape” and “sensible cinematic intra-activity”, feature here as a multisensorial methodology for transdisciplinary transgender studies and feminist film theory as well as visual culture at large. / Trans Cinema and its Exit Scapes är en kritisk och kreativ intervention med fokus på kulturella representationer av kroppar som bryter mot en könsbinär ordning i samtida film. Studien argumenterar för möjligheten att hitta utrymmen för “disidentification”, så kallade “exit scapes” inom filmerna. Exit scapes stör den dominanta filmiska ordning som skapats för transkaraktären, en ordning som är förbunden med berättelser om diskriminering, förödmjukelse och våld. Inom Trans Cinema, i filmer som exempelvis Hedwig and the Angry Inch (2001), Transamerica (2005), Romeos (2011) and Laurence Anyways (2012), öppnar scener med sång, dans och drömmar upp för andra former av engagemang med filmerna. Som det argumenteras för i avhandlingen tillåter dessa ett kritiskt omformulerande av, och ett nytt affirmativt sätt att föreställa sig, transkroppslighet. Syftet med den här studien är att undersöka den utopiska och hoppfulla potential som finns inom transfilm utifrån ett kritiskt transfeministiskt perspektiv. Även om studien främst riktar sig till trans entrants som “åskådare” eller läsare, så har den en bred teoretisk bas hämtad från verk av en lång rad feministiska forskare inom kulturfältet, såsom Sara Ahmed, Susan Stryker, José Esteban Muñoz, Trinh T. Minh-Ha, Karen Barad och Donna Haraway. Denna avhandling skissar filmiska spatiotemporaliteter, vilka öppnar för möjligheter av utopiska värdsliga och transsubjektiva tillblivelser genom utvecklandet av olika teoretiska begrepp. Genom ett kritiskt förhållningssätt till audiovisualitet och feministisk filmteori, revideras och omformuleras haptisk åskådarskapsteori och dess kritik i en västerländsk okularcentrism genom olika teoretiska innovationer. De metodologiska verktygen som utvecklas i avhandlingen, såsom “the entrant”, “the exit scape” samt “sensible cinematic intra-activity” utgör här funktionen som multisensorisk metodologi för transdisciplinära transstudier, feministisk filmteori samt för visuell kultur i stort.
400

Investigating the Application and Sustained Effects of Stochastic Resonance on Haptic Feedback Sensitivity in a Laparoscopic Task

Wilcox, Kara Liane 08 June 2023 (has links)
No description available.

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