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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.
11

User-centered Virtual Environment Assessment And Design For Cognitive Rehabilitation Applications

Fidopiastis, Cali 01 January 2006 (has links)
Virtual environment (VE) design for cognitive rehabilitation necessitates a new methodology to ensure the validity of the resulting rehabilitation assessment. We propose that benchmarking the VE system technology utilizing a user-centered approach should precede the VE construction. Further, user performance baselines should be measured throughout testing as a control for adaptive effects that may confound the metrics chosen to evaluate the rehabilitation treatment. To support these claims we present data obtained from two modules of a user-centered head-mounted display (HMD) assessment battery, specifically resolution visual acuity and stereoacuity. Resolution visual acuity and stereoacuity assessments provide information about the image quality achieved by an HMD based upon its unique system parameters. When applying a user-centered approach, we were able to quantify limitations in the VE system components (e.g., low microdisplay resolution) and separately point to user characteristics (e.g., changes in dark focus) that may introduce error in the evaluation of VE based rehabilitation protocols. Based on these results, we provide guidelines for calibrating and benchmarking HMDs. In addition, we discuss potential extensions of the assessment to address higher level usability issues. We intend to test the proposed framework within the Human Experience Modeler (HEM), a testbed created at the University of Central Florida to evaluate technologies that may enhance cognitive rehabilitation effectiveness. Preliminary results of a feasibility pilot study conducted with a memory impaired participant showed that the HEM provides the control and repeatability needed to conduct such technology comparisons. Further, the HEM affords the opportunity to integrate new brain imaging technologies (i.e., functional Near Infrared Imaging) to evaluate brain plasticity associated with VE based cognitive rehabilitation.
12

Head-Mounted Displays for Harvester Operators – A Pilot Study / Head-mounted displays för skördaroperatörer – En pilotstudie

Nordlie, Anders, Till, Staffan January 2015 (has links)
Harvester operators are handling large amounts of information while processing trees. Primarily by looking at the close environment, the trees, and the harvesting head, but also through the bucking display placed in front of the operator. Head-mounted displays have been under development since the 1960s but have yet to find any major applications where they excel outside military aircrafts despite numerous tries. This master thesis aims at evaluating the usability for head-mounted displays (HMDs) and augmented reality (AR) technology within forestry, by answering the research question: Are HMDs suited for displaying information in harvesters? What information is suitable to display in HMDs and how should it be displayed for best effect? A literature review about the current state of the art of HMDs and AR has been compiled which can be read independently. Qualitative user studies have been performed to map the current interactions of harvester operators by observation and interviews in the field. Interviews have been made with subject matter experts in relating fields. The insights gathered from the user studies led to three interface designs for bucking which were designed, prototyped and tested for usability in a harvester simulator. Ideas for other more immersive uses of the HMD were also designed. For bucking is assortment and species the most important information for the operators, contrary to how it is displayed today, where diameter and fed length is presented as the most significant information. Near machine navigation is a problem area which may be solved with AR. Operators participating in the test were positive towards the technology after testing. Our conclusion is that HMDs shows enough promise and performance to be evaluated further by tests in the field. Weight, brightness, and a non-occluding design are the most important properties for an HMD for harvesters. / Skördaroperatörer hanterar stora mängder information vid fällning och aptering. Främst genom att titta på omgivningen, träden och aggregatet men också via apteringsskärmen framför sig. Head-mounted Displays (HMDs) har varit under utveckling sedan 1960 talet men har hittat få tillämpningar utanför det militära flyget trots många studier. Detta examensarbete försöker utreda om HMDs och augmented reality (AR) är lämpliga tekniker för det mekaniserade skogsbruket genom att svara på frågorna: Är HMDs lämpliga för att visa information för skördaroperatörer? Vilken information skall då visas och hur ska den visas på bästa sätt? En litteraturstudie om HMDs och AR har genomförts och kan läsas fristående. Kvalitativa användarstudier har genomförts för att kartlägga skördaroperatörers arbete genom observationer och intervjuer. Intervjuer har även gjorts med experter inom närliggande områden. Från studierna har tre gränssnitt utvecklats och testats i en skördarsimulator. Idéer för AR gränssnitt har även de utformats. För aptering är sortiment och trädslag den viktigaste informationen att visas, i motsats till dagens gränssnitt där diameter och utmatad längd visas tydligast. Navigation i närheten av skördaren är ett problemområde som skulle kunna lösas med hjälp av AR. Operatörer i användartester har varit positiva till tekniken. Vår slutsats är att HMDs är tillräckligt lovande för fortsatta tester i fält för skördaroperatörer. Vikt, ljusstyrka och en design som inte skymmer sikten är de viktigaste faktorerna för en HMD för skördarbruk.
13

Použití rozšířené reality při tréninku a provádění údržby letadel / Augmented Reality for Training and Execution of Airplane Maintenance

Košík, Michal January 2013 (has links)
This thesis deals wtih augmented reality applied to aircraft maintenance which is widely explored here. Furthermore, a reseach is done on the previous work done in this field. A video data-set is acquired from LET - a manufacturer of LET L-410 aircraft and an application is created in order to test possibilities of using augmented reality in aircraft maintenance. The result and proposals of the future work can be found in this thesis as well
14

Mixed Reality Displays in Warehouse Management : A study revealing new possibilities for Warehouse Management and Tangar / ”Mixed Reality”-skärmar inom lagerarbete : En studie som åskådliggör nya möjligheter för lagerarbete och Tangar

Karlsson, Adam January 2019 (has links)
This work has investigated how head-mounted-displays can enable more efficient and better work conditions for warehouse workers. Head-mounted-displays have increased in popularity among companies because of an increase in the field of e-commerce, therefore warehouse labour was an interesting area to review. The purpose of this project has been to investigate how head-mounted-displays can simplify warehouse work and to find an area where Tangar can be utilized. Tangar is an application to facilitate indoor navigation by helping users to reach points of interest. Through a mixed methodology approach that utilizes both quantitative and qualitative methods, a broad understanding in warehouse and inventory management have been established. The potentials of head-mounted display were evaluated using empirical and theoretical studies. Based on an early concept that was evaluated by a collaboration with a warehouse-solution company, factors that are of importance in warehouse management were identified. A decision to direct the project towards order picking was taken as it is a fundamental process within warehouse management. Three concepts were generated that harness the benefits of head-mounted-displays. With an informed decision the benefits for each of the concepts were compared with important parameters for a profitable warehouse management. It turned out that "Pick-by-Light", a common system in warehouse management, can be made virtual using head-mounted-displays. Since the system had never previously been operated virtually, an extensive study needed to be done in order to evaluate the viability in order-picking to propose a final concept. An experimental environment was set for the empirical studies, and two other common order picking systems were compared to the virtual Pick-by-Light system. Quantitative data in the form of time measurements from the order picking as well as picking errors and qualitative data from a NASA-TLX survey, was extracted from twelve users. A total of 360 samples from the quantitative study and 36 questionnaires from the qualitative study was then analysed. The result resembled those from similar studies with a conventional Pick-by-Light system. Thus, parallels were drawn that indicated that the virtual system had good potential to perform at least as well as a regular Pick-by-Light. A virtual Pick-by-Light system might be able to reduce implementation-, work- and operational costs as the use of material is replaced by a virtual product, and also no installation is required. With the combination of Tangar, there is also a potential that a virtual Pick-by-Light system could be more efficient and accurate. The disadvantages of the conventional Pick-by-Light system are also that confirmations are ineffective and that workers find it difficult to get an overview of pickplaces. Which can potentially be eliminated with the proposed concept. However, a new generation of hardware and further studies are required in order to establish a final concept. The Magic Leap One, which is the head-mounted-display used in the project, is new. Many problems regarding the display have been discovered during the project and affected the results of the user studies. Further studies need to be done with other displays to determine the validity of the results of this work. In summary, this work gives an introduction in how "Mixed-reality" can be used in warehouse management and recommendations for continued work. / Det här arbetet har undersökt hur huvudmonterade skärmar kan möjliggöra ett effektivare och bättre arbete för lager-personal. Huvudmonterade skärmar har ökat i popularitet bland företaget på grund av ökningen inom e-handel och därför var lagerarbete ett intressant område att undersöka. Syftet med det här projektet har varit att undersöka hur huvudmonterade skärmar fortsatt skulle kunna förenkla lagerarbete samt att ta hitta ett område där Tangar kan användas. Tangar är en applikation som förenklar inomhus navigering genom att leda användaren till valda intressepunkter. Genom en metodisk undersökning som utnyttjar både kvantitativa och kvalitativa metoder, har en bred bakgrund inom lagerhantering kunnat upprättas. Potentialen av att använda huvudmonterade skärmar har undersökts genom empiriska och teoretiska studier. Baserat på ett tidigt koncept som utvärderas genom ett samarbete med ett sakkunnigt företag, identifierades flertalet faktorer som är av vikt i lagerhantering. Ett beslut om att rikta projektet mot order-plockning togs då det är en fundamental process inom lagerabete. Tre koncept genererades som utnyttjar fördelarna med huvudmonterade skärmar. Genom att ta ett informativt beslut, kunde fördelarna för var och ett av koncepten jämföras med viktiga parametrar för ett lönsamt lagerarbete. Det visade sig att ”Pick-by-Light”, ett vanligt system inom lagerhantering, kunde göras virtuellt med hjälp av huvudmonterade skärmar. I och med att systemet tidigare aldrig utförts virtuellt, behövdes en omfattande studie göras för att evaluera dess potential inom order-plockning för att kunna föreslå ett slutgiltigt koncept. En experimentell miljö sattes upp som ram för de empiriska studierna och två andra vanliga order-plocknings system kunde jämföras mot det virtuella Pick-by-Light systemet. Kvantitativa data i form av orderplockningstider samt plock-fel och kvalitativa data från observationer samt en NASA-TLX enkät, kunde extraheras från tolv användare. Totalt kunde 360 stickprov från den kvantitative studien och 36 enkäter från den kvalitative studien därefter analyseras. Resultatet liknade det som observerats i liknande studier där ett vanligt Pick-by-Light system evaluerats. Därmed kunde paralleller dras som visade att det virtuella systemet hade god potential till att kunna prestera åtminstone lika bra som ett vanliga Pick-by-Light systemet och ett koncept togs fram för vidare utveckling. Ett virtuellt Pick-by-Light system skulle kunna reducera implementerings-, arbetes- samt driftkostnader i och med att materialåtgången ersätts av en virtuell produkt, samt att ingen installation krävs. I och med kombinationen av Tangar finns det även potential att konceptet är mer effektivt och exakt. De nackdelar med det traditionella Pick-by-Light systemet är också att plock-bekräftelser görs ineffektivt och att arbetare har svårt att få en överblick gällande plockställen. Vilket skulle kunna elimineras med det föreslagna konceptet. Dock krävs en ny generation hårdvara och vidare studier för att kunna fastställa ett slutgiltigt koncept. Magic Leap One, som är den huvudmonterade skärmen som används i projektet är väldigt ny. Många problem gällande displayen har upptäckts under projektet och påverkat resultatet av användarstudierna. Fortsatta studier skulle behöva göras med andra displayer för att fastställa validiteten av resultaten från det här arbetet. Sammanfattningsvis ger det här arbetet en introduktion om hur ”Mixed-reality” kan användas inom lagerhantering samt rekommendationer till fortsatt arbete.
15

Convergence in mixed reality-virtuality environments : facilitating natural user behavior

Johansson, Daniel January 2012 (has links)
This thesis addresses the subject of converging real and virtual environments to a combined entity that can facilitate physiologically complying interfaces for the purpose of training. Based on the mobility and physiological demands of dismounted soldiers, the base assumption is that greater immersion means better learning and potentially higher training transfer. As the user can interface with the system in a natural way, more focus and energy can be used for training rather than for control itself. Identified requirements on a simulator relating to physical and psychological user aspects are support for unobtrusive and wireless use, high field of view, high performance tracking, use of authentic tools, ability to see other trainees, unrestricted movement and physical feedback. Using only commercially available systems would be prohibitively expensive whilst not providing a solution that would be fully optimized for the target group for this simulator. For this reason, most of the systems that compose the simulator are custom made to facilitate physiological human aspects as well as to bring down costs. With the use of chroma keying, a cylindrical simulator room and parallax corrected high field of view video see-though head mounted displays, the real and virtual reality are mixed. This facilitates use of real tool as well as layering and manipulation of real and virtual objects. Furthermore, a novel omnidirectional floor and thereto interface scheme is developed to allow limitless physical walking to be used for virtual translation. A physically confined real space is thereby transformed into an infinite converged environment. The omnidirectional floor regulation algorithm can also provide physical feedback through adjustment of the velocity in order to synchronize virtual obstacles with the surrounding simulator walls. As an alternative simulator target use, an omnidirectional robotic platform has been developed that can match the user movements. This can be utilized to increase situation awareness in telepresence applications.
16

Use of head mounted virtual reality displays in flight training simulation / VR-glasögons användbarhet för pilotträningssimulering

Gustafsson, Anders January 2018 (has links)
The purpose of this thesis was to evaluate currently commercially available head mounted virtual reality displays for potential use in pilot training simulators. For this purpose acommercial simulator was modified to display the virtual environment in an Oculus RiftDK2 headset. A typical monitor based setup was used to provide a set of hardware requirements which the VR implementation had to meet or exceed to be considered potentially usable for pilot training simulators. User tests were then performed with a group of users representative of those normally using pilot training simulators, including both pilots and engineers working with simulator development. The main focus of the user tests was to evaluate some potential weaknesses found in the technical comparison (such as when a measured parameter was close to the lower limit defined by the monitor based setup) and to make a measurement of the usability of the VR implementation. The results from the technical comparison showed that the technical requirements were met and in most cases also exceeded. There were however some potential weaknesses revealed during the user tests, which included screen resolution and the field of view. There was one main critical deficiency found during the user tests. This was the lack of interaction with the aircraft as users were only able to interact with the flight stick and throttle lever. While this enabled the users to control many aspects of the aircraft (by using buttons and other controls fitted on the flight stick/throttle) in a training scenario a user also has to be able to interact with other switches and/or monitors in the cockpit. This was however a known limitation of the implementation and thus didn’t affect the tested parts of the simulator. The user tests also confirmed that the resolution was a potential problem, but that the overall usability was high. Thus the VR implementation had potential for use in a pilot training simulator, if the critical issues found during the user tests were solved.
17

An Analysis of Enabling Techniques for Highly-Accessible Low-Cost Virtual Reality Hardware in the Collaborative Engineering Design Process

Coburn, Joshua Q. 01 June 2017 (has links)
While there currently exists a great deal of research in the literature demonstrating various engineering applications for virtual reality (VR) and the benefits of these applications, VR adoption has been slow in part because of the high cost and resources required to setup and maintain the hardware for these applications. However, in the last 5 years, a new generation of VR hardware has emerged with cost and resource requirements which are a small fraction of previous hardware. This work begins with a survey of this newly available hardware summarizing recent advances for providing virtual input to all of the five human senses. The literature review then proceeds to highlight previous research into improving various aspects of the Engineering Design Process by using VR applications. The literature review concludes that given the significantly improved cost to benefit ratio of this new hardware, a tipping point has been reached where companies will see benefits from providing their engineering workforce with general access to VR hardware. From the conclusions drawn in the literature review, this work proceeds to explore and answer two main questions related to connecting and collaborating via this new VR hardware. The first question seeks to understand the trade-offs between cybersickness and disorientation from different styles of moving users in a collaborative VR environment (CVE). Since a CVE can be much larger than the physical world it is sometimes necessary to move the virtual participant which can cause cybersickness and disorientation. Understanding this trade-off is one key to creating a usable CVE. It is found that many users are willing to experience some mild cybersickness to significantly reduce the amount of disorientation experienced in a CVE. However, a second group of users are not willing to make this trade and hence require the ability to customize the CVE for their preferred trade-off between cybersickness and disorientation. The second question seeks to understand how a CVE with support for natural gestures can improve communication about complex 3D data over video conferencing which is the current standard for remote collaboration. It is found that such a CVE implemented with the latest low-cost consumer-grade VR hardware can improve communication speed up to 45% while also improving the accuracy of the communication. In addition, it was found that gestures in the CVE were much more effective and natural than mouse gestures in Skype, 93% of participants preferred the CVE over current video conferencing software, and 86% of participants stated they would like to have access to VR tools in their workplace.
18

An Analysis of Enabling Techniques for Highly-Accessible Low-Cost Virtual Reality Hardware in the Collaborative Engineering Design Process

Coburn, Joshua Q. 01 June 2017 (has links)
While there currently exists a great deal of research in the literature demonstrating various engineering applications for virtual reality (VR) and the benefits of these applications, VR adoption has been slow in part because of the high cost and resources required to setup and maintain the hardware for these applications. However, in the last 5 years, a new generation of VR hardware has emerged with cost and resource requirements which are a small fraction of previous hardware. This work begins with a survey of this newly available hardware summarizing recent advances for providing virtual input to all of the five human senses. The literature review then proceeds to highlight previous research into improving various aspects of the Engineering Design Process by using VR applications. The literature review concludes that given the significantly improved cost to benefit ratio of this new hardware, a tipping point has been reached where companies will see benefits from providing their engineering workforce with general access to VR hardware. From the conclusions drawn in the literature review, this work proceeds to explore and answer two main questions related to connecting and collaborating via this new VR hardware. The first question seeks to understand the trade-offs between cybersickness and disorientation from different styles of moving users in a collaborative VR environment (CVE). Since a CVE can be much larger than the physical world it is sometimes necessary to move the virtual participant which can cause cybersickness and disorientation. Understanding this trade-off is one key to creating a usable CVE. It is found that many users are willing to experience some mild cybersickness to significantly reduce the amount of disorientation experienced in a CVE. However, a second group of users are not willing to make this trade and hence require the ability to customize the CVE for their preferred trade-off between cybersickness and disorientation. The second question seeks to understand how a CVE with support for natural gestures can improve communication about complex 3D data over video conferencing which is the current standard for remote collaboration. It is found that such a CVE implemented with the latest low-cost consumer-grade VR hardware can improve communication speed up to 45% while also improving the accuracy of the communication. In addition, it was found that gestures in the CVE were much more effective and natural than mouse gestures in Skype, 93% of participants preferred the CVE over current video conferencing software, and 86% of participants stated they would like to have access to VR tools in their workplace.
19

The Social World Through Infants’ Eyes : How Infants Look at Different Social Figures

Schmitow, Clara A. January 2012 (has links)
This thesis aims to study how infants actively look at different social figures: parents and strangers. To study infants’ looking behavior in “live” situations, new methods to record looking behavior were tested. Study 1 developed a method to record looking behavior in “live” situations: a head-mounted camera. This method was calibrated for a number of angles and then used to measure how infants look at faces and objects in two “live” situations, a conversation and a joint action. High reliability was found for the head-mounted camera in horizontal positions and the possibility of using it in a number of “live” situations with infants from 6 to 14 months of age. In Study 2, the head-mounted camera and a static camera and were used in a “live” ambiguous situation to study infants’ preferences to refer to and to use the information from parents and strangers. The results from Experiment 1 of Study 2 showed that if no information is provided in ambiguous situations in the lab, infants at 10 months of age look more at the experimenter than at the parent. Further, Experiment 2 of Study 2 showed that the infants also used more of the emotional information provided by the experimenter than by the parent to regulate their behavior.  In Study 3, looking behavior was analyzed in detail when infants looked at pictures of their parents’ and strangers’ emotional facial expressions. Corneal eye tracking was used to record looking. In this study, the influence of identity, gender, emotional expressions and parental leave on looking behavior was analyzed. The results indicated that identity and experience of looking at others influences how infants discriminate emotions in pictures of facial expressions. Fourteen-month-old infants who had been with both parents in parental leave discriminated more emotional expressions in strangers than infants who only had one parent on leave. Further, they reacted with larger pupil dilation toward the parent who was actually in parental leave than to the parent not on leave. Finally, fearful emotional expressions were more broadly scanned than neutral or happy facial expressions. The results of these studies indicate that infants discriminate between mothers’, fathers’ and strangers’ emotional facial expressions and use the other people’s expressions to regulate their behavior. In addition, a new method, a head-mounted camera was shown to capture infants’ looking behavior in “live” situations.
20

The use of head mounted displays (HMDs) in high angle climbing : implications for the application of wearable computers to emergency response work.

Woodham, Alexander, Timothy January 2015 (has links)
As wearable computers become more ubiquitous in society and work environments, there are concerns that their use could be negatively impactful in some settings. Previous research indicates that mobile phone and wearable computer use can impair walking and driving performance, but as these technologies are adopted into hazardous work environments it is less clear what the impact will be. The current research investigated the effects that head mounted display use has on high angle climbing, a task representative of the extreme physical demands of some hazardous occupations (such as firefighting or search and rescue work). We explored the effect that introducing a secondary word reading and later recall task has on both climbing performance (holds per meter climbed and distance covered), and word reading and recall (dual-task effects). We found a decrease in both climbing performance and word recall under dual task conditions. Further, we examined participant climbing motion around word presentation and non-word presentation times during the climbing traverse. We found that participants slowed around word presentations, relative to periods without word presentation. Finally, we compared our results to those found in previous research using similar dual-tasking paradigms. These comparisons indicated that physical tasks may be more detrimental to word recall than seated tasks, and that visual stimuli might hinder climbing performance more than audible stimuli. This research has important theoretical implications for the dual-tasking paradigm, as well at important practical implications for emergency response operations and other hazardous working environments.

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