Browsing by Subject "Virtual Reality"

Now showing 1 - 19 of 19

Application, rendering and display of automotive paint.
(2009-11) Konieczny, Jonathan M.
New computer graphics tools are developed for use in the automotive paint design and paint application industries. These tools are designed to aid in every aspect of automotive painting from initial paint design all the way to viewing a final spray paint job. This thesis also provides new computer graphics techniques by leveraging industrial appearance standards and measurement instruments to yield new interaction, rendering and display algorithms. First, a system is introduced for the simulation of spray painting. Head mounted display goggles are combined with a tracking system to allow users to paint a virtual surface with a spray gun. Ray tracing is used to simulate droplets landing on the surface of the object, allowing arbitrary shapes and spray gun patterns to be used. This system is combined with previous research on spray gun characteristics to provide a realistic simulation of the spray paint including the effects of viscosity, air pressure, and paint pressure. Experiments were performed to validate the system for use as a training tool. Next, a virtual airbrush tool is introduced. The basic particle simulation used in the spray paint system is modified to include the finer control needed for airbrushing. Paint mixing between colors applied to the surface is modeled using Kubelka-Munk theory. Computerized stencils, including semi-permeable stencils, can be manually positioned by the artist or projected onto the object’s surface. The resulting airbrush system can be used by airbrush artists to both practice their craft as well as to decorate virtual models. The dissertation then utilizes an industrial measurement instrument to simulate the surface roughness in automotive paint finishes. This simulation is integrated with a design interface to enable industry professionals to devise new paints that have detailed surface effects. The industrial measurement device can also be used to rapidly measure and render real world materials without the need for elaborate full BRDF acquisition tools. Finally, the surface model developed in this research can be used to study human detection of small scale surface roughness. Lastly, new projection systems are introduced to display the paints generated by the previous algorithms. A desired paint is projected onto the surface of an object, making that object appear to be painted with that material. This allows painters to evaluate how the final painted surface will look in a very natural way. A novel projection system is also described in which the user can hold and evaluate a flexible sample of virtual paint. This provides a more compelling display of the paint than a standard 2D monitor can generate. These display methods can also be used to display materials other than paint, potentially benefiting a large range of industries. The combination of these tools is intended to allow spray painters to design paints, paint them onto an automobile or other object, and verify exactly what the result will look like before ever having to manufacture the paint itself. The use of these tools could therefore reduce wasted paint, speed up training times, and allow for precise design of automobile appearance: all before ever manufacturing any real paint. In addition to aiding paint industries, these tools enhance the current state of the art in computer graphics. The airbrush tool provides a new texture creation system that existing airbrush artists can use with little to no training; the surface roughness simulation provides enhanced rendering of automotive paint that could be used in movies and games; and the projection display system improves the state of the art in augmented reality systems.
Behavior Monitoring Using Visual Data and Immersive Environments
(2017-08) Fasching, Joshua
Mental health disorders are the leading cause of disability in the United States and Canada, accounting for 25 percent of all years of life lost to disability and premature mortality (Disability Adjusted Life Years or DALYs). Furthermore, in the United States alone, spending for mental disorder related care amounted to approximately $201 billion in 2013. Given these costs, significant effort has been spent on researching ways to mitigate the detrimental effects of mental illness. Commonly, observational studies are employed in research on mental disorders. However, observers must watch activities, either live or recorded, and then code the behavior. This process is often long and requires significant eﬀort. Automating these kinds of labor intensive processes can allow these studies to be performed more eﬀectively. This thesis presents efforts to use computer vision and modern interactive technologies to aid in the study of mental disorders. Motor stereotypies are a class of behavior known to co-occur in some patients diagnosed with autism spectrum disorders. Results are presented for activity classification in these behaviors. Behaviors in the context of environment, setup and task were also explored in relation to obsessive compulsive disorder (OCD). Cleaning compulsions are a known symptom of some persons with OCD. Techniques were created to automate coding of handwashing behavior as part of an OCD study to understand the difference between subjects of different diagnosis. Instrumenting the experiment and coding the videos was a limiting factor in this study. Varied and repeatable environments can be enabled through the use of virtual reality. An end-to-end platform was created to investigate this approach. This system allows the creation of immersive environments that are capable of eliciting symptoms. By controlling the stimulus presented and observing the reaction in a simulated system, new ways of assessment are developed. Evaluation was performed to measure the ability to monitor subject behavior and a protocol was established for the system's future use.
Cybersickness in Virtual Reality Head-Mounted Displays: Examining the Influence of Sex Differences, Vehicle Control and Postural Precursors
(2021-05) Curry, Christopher
The auspicious future of virtual reality could be thwarted by cybersickness.Cybersickness can be thought of as a subset of motion sickness and like motion sickness is more common among women than among men. Additionally, motion sickness is more common among passengers than among drivers. In this dissertation research, it was asked whether these two effects might interact. In a yoked-control design using a head-mounted display, one member of each pair drove a virtual automobile, while the other member watched a recording of the driver’s performance. In Chapter 2, it is explored whether such an interaction existed and the overall rates of cybersickness amongst these two groups. Previous research has shown that the subjective experience of cybersickness often is preceded by distinctive patterns of movement. In Chapter 3, it is examined whether such postural precursors of cybersickness might exist before participants were exposed to a virtual driving game presented. In this chapter, participants standing body sway was gathered while participants performed simple visual tasks (staring at a blank page vs. counting target letters in a block of text). In Chapter 4, movement of the head and torso was recorded while participants were exposed to a driving video while seated. These three chapters further inform the current understanding of cybersickness, and whether certain factors of the virtual environment may increase the likelihood of individuals becoming cybersick. Furthermore, chapters 3 and 4 further explore whether movement data can be used as an objective predictor in cybersickness research. If movement data further proves to be an objective predictor then this approach can be one iii of many approaches to assuage cybersickness for highly susceptible individuals.
Design and Evaluation of Dynamic Field-of-View Restriction Techniques to Mitigate Cybersickness in Virtual Reality
(2022-09) Wu, Fei
Although virtual reality has been gaining in popularity, users continue to report discomfort during and after the use of VR applications, and many experience symptoms associated with cybersickness. To mitigate this problem, dynamic field-of-view (FOV) restriction is a common technique that has been widely implemented in commercial VR games. FOV restriction artificially reduces the field of view during movement to limit optical flows and reduce discomfort caused by the mismatch between virtual motion and physical motion. FOV restriction has been shown in numerous studies to improve comfort and enhance user experience in virtual reality. The standard dynamic FOV restriction is created by adding a symmetrical black opaque mask at the periphery of the user’s filed-of-view and its size changes only with the user's virtual velocity. It does not take into account any differences in users, virtual environments, or other usage conditions. This simplistic implementation leads to some limitations. The first limitation is that the FOV restriction reduces users' visibility of the virtual environment and can negatively impact their subjective experience. The second limitation is that the unblocked imagery when applying restrictor is usually in the center of the field of view, which is incompatible with the users' eye movements during locomotion. The third limitation is that the classical restrictor is scaled by the velocity and angular velocity of users' virtual movements. This design assumes that users feel the same cybersickness when they experience the same velocity, which is unrealistic. Beyond these limitations, there is a lack of scientific understanding of how to effectively apply FOV restrictions for different types of virtual environments and virtual motions. This thesis presents four major contributions to the existing dynamic FOV restriction research. First, I present a novel technique known as passthrough FOV restriction, which combines the dynamic field of view modification with rest frames generated from 3D scans of the physical environment. The informal testing suggests that this approach is a promising method for reducing motion sickness and improving user safety at the same time. Secondly, I present a novel asymmetric field-of-view restrictor known as the ground-visible restrictor, which maintains the visibility of the ground plane during movement. User studies showed that ground-visible FOV restriction offers benefits for user comfort, postural stability, and a subjective sense of presence. Thirdly, I provide another variant of FOV restriction, referred to as the side restrictor, which expands side visibility and maintains restriction during rotation. A user study evaluated the new technology and demonstrated its benefits in reducing cybersickness and discomfort and improving visibility. Finally, I present an adaptive restrictor that uses the optical flow amount to determine the position and size of the restriction. A mixed design study investigated its performance and confirmed its superiority over traditional restrictors in providing a better subjective user experience.
Designing VR for Understanding Physiological Effects of Embodiment and Multi-sensory Modalities
(2020-08) Kothapalli, Sai
Virtual Reality (VR) is becoming more and more recognized in various fields as a way to train and educate people. VR has become popular for its spatial audio-visual perception of alternate virtual environments. One other reason it is becoming more accessible is because of larger companies like Google, Microsoft, Facebook, and Apple investing a lot of money to do VR research to roll out VR gear that is much more affordable than they used to be five years ago. In this thesis, we developed software that can be used to conduct VR studies and measure physiological responses related to immersion and presence experienced in VR. The sense of presence in virtual environments may be a key factor in how we perceive and act in VR. Recent studies in VR have also shown that embodiment can improve immersion and engagement. Embodiment is a sense of having a virtual body that a user can relate to as being their own. But giving a virtual avatar for the user is not easy as it requires hardware synchronization with the VR application. Moreover, collecting physiological signal data to understand the effects of embodiment involves sensors that need to be used alongside this other equipment. The main component of this thesis is a software system for research studies that explore the effect of embodiment and multi-sensory modalities on the physiology of a participant. There has been much growth in how virtual reality technology is being used in various areas like planning and architecture, medical surgeries, education, and research. VR offers a real-time immersive experience, interactive simulation. Our thesis is a building block that encourages future researchers to do large scale expansive studies to understand the psychophysiological effects of body ownership and to also increase the number of studies that can be done by a larger array of researchers. By understanding these effects, we can further explore the possibilities of VR in the areas mentioned above. We also discuss how embodiment will affect the sense of presence of a person in a virtual environment. Moreover, we will show how our software can be used to present various stimuli easily and record physiological responses using a wearable sensor. We built a virtual environment for this purpose which integrates hardware together to enable embodiment, multiple-sensory modalities, and collect physiological evidence.
Effects of Avatar Hand-size Modifications on Size Judgments of Familiar and Abstract Objects in Virtual Reality
(2019-06) Patterson, Zachary
Many research studies have investigated spatial understanding within virtual envi- ronments, ranging from distance estimation, size judgments, and perception of scale. Eventually, this knowledge will help us to create virtual environments that better match our spatial abilities within natural environments. To further understand how people interpret the size of virtual objects, we present an experiment that utilizes a proprioceptive-based size estimation measure designed to elicit a three-dimensional judgment of an object’s size using a box-sizing task. Participants viewed both ab- stract and familiar objects presented within action-space in a virtual environment and were asked to make an axis-aligned box the same size as the object they previously observed. A between-subjects manipulation modified a participant’s avatar hand size to be either 80%, 100% or 120% of their measured hand size. Results indicate that the avatar hand size manipulation scales various factors of these size judgments in the three dimensions. Additionally, whether an object was abstract or a familiar size object produced distinctly different size judgments.
Expressive spatial Interfaces for scientific visualization and artistic 3D Modeling
(2014-07) Jackson, Bret Lowell
This dissertation explores spatial human-computer interaction techniques to improve the control and expressiveness of 3D interactions. It investigates the requirements necessary for users to work more effectively with next-generation spatial interfaces, specifically in the context of scientific visualization and artistic 3D modeling where users currently struggle to express complex spatial concepts.Examples of expressive spatial interfaces are presented and evaluated. In particular, we present new techniques for combining multi-touch with free-hand gestures for navigating visualizations and performing 3D surface modeling operations. Techniques for selecting and filtering volumetric data using lightweight props as well as active force-feedback are also introduced. Additionally, we present a spatial modeling interface for artistic 3D modeling using contextual interpretation of the user's input. Several conclusions are drawn from these examples. Rich, parallel input and output streams enabled by recent advances in tracking hardware are particularly important for expressive interfaces. Additionally, there is a need for tighter integration of two and three-dimensional data and input. Contextual interpretation of user input enables users to specify more complex 3D concepts. Finally, many spatial tasks require immediate feedback to be expressive.The primary contribution of this dissertation is a new class of interaction techniques called Expressive Spatial Interfaces that advance beyond the limited pointing and rotating interactions common in current-generation spatial interfaces. The techniques presented here can have a powerful impact on shaping the future of expressive spatial human-computer interaction with 3D graphics.
Immersive Anatomical Scenes that Enable Multiple Users to Occupy the Same Virtual Space: A Tool for Surgical Planning and Education
(2019-01) Deakyne, Alex
3D modeling is becoming a well-developed field of medicine, but its applicability can be limited due to the lack of software allowing for easy utilizations of generated 3D visualizations. By leveraging recent advances in virtual reality, we can rapidly create immersive anatomical scenes as well as allow multiple users to occupy the same virtual space: i.e., over a local or distributed network. This setup is ideal for pre-surgical planning and education, allowing users to identify and study structures of interest. I demonstrate here such a pipeline on a broad spectrum of anatomical models and discuss its applicability to the medical field and its future prospects.
The Impact Of Different Types Of Personalized Self-Avatar And Their Properties On The User Satisfaction And Spatial Perception In Virtual Environment
(2020-03) Deng, Zhihang
Traditionally, most Virtual Reality (VR) applications use a generic avatar model as a digital representation of one's own body that can provide a reference as a means of localization and an interactive tool in the immersive virtual environment to users. With the development of depth-sensing technology, RGB-D data can be used to perform 3D reconstruction, thereby providing a personalized self-representation to the user in VR. However, this approach is not without its limitations; these include the following: expensive equipment, setup time, and difficulty providing stimuli that are naturally available in the real-world. The latter limitation, we believe this may diminish the VR experience. One sense that is lost in VR is haptic feedback. While research is ongoing to improve the ability to incorporate this sense in VR, many challenges remain to be addressed to support such functionality robustly. This thesis looks to address some of these limitations. First, we present a video-based approach that can provide a realistic personalized self-representation that allows users to see their own body easily and quickly. After this method was developed, we conducted three user case studies to understand which approach, model-based hand and video-based hand, is inherently more promising in VR. In the first user case study, we used visual/haptic cue conflict paradigm to quantitatively compare participants' inherent sense of trust in the visual representation of their hands when a video-based vs model-based approach was used for the hand representation during passive haptic interactions in a VR setting. This experiment found equivalently stronger visual dominance in each of the hand representation conditions versus a control condition of no visible hands suggesting equivalent potential promise in each of these representational approaches. Furthermore, we also found a surprisingly small range of imperceptibility of visual displacements of the hand locations coincident with bi-lateral haptic feedback. The second experiment focused on the use of model-based hands and assessed the impact of the self-likeness of the model-based self-representation (using one's own scanned hand versus the scanned hand of someone else) on multiple measures of user satisfaction and task performance in three different types of tasks. We found that ratings of perceived visual realism were significantly higher, overall, when participants used their own scanned hand vs. the scanned hand of another participant, but we did not find significant differences in ratings of agency, ownership, presence, or functional realism. In our last experiment, we focused on studying video-based hands and examined the importance of applying realistic shading and shadows to the hand representation when using the RGB-D data approach. We first investigated the influence of perceived-correct vs incorrect hand brightness on the accuracy with which participants could identify hand/surface contact at different hand/surface distances. The results of this study showed decrease accuracy of contact detection both under lower levels of scene illumination and when there was a mismatch between the hand and scene brightness. We then compared contact detection accuracy under three different shadow conditions: when the video-based hand did not cast a shadow, when the 2.5D mesh of the video hand was used to cast a shadow, and when the video hand's shadow was defined by a concurrently tracked (but not visible) generic 3D hand model. Our result found a significant main effect of the distance from the hand to the surface on the likelihood of contact perception, but no significant effect of the shadow type. In summary, this thesis examines the effects of multiple aspects of model-based and video-based hand representations on multiple measures of user satisfaction and performance in various VR tasks. The results that are presented in this thesis have the potential to inform future applications that use a video-based or model-based approach to represent users' hands in VR.
Motion sickness, virtual reality and postural Stability.
(2009-12) Merhi, Omar Ahmad
Motion sickness has been anecdotally reported to occur in the video game community. No confirmation of these reports has been documented by research studies in a laboratory setting. The present investigation was motivated, in part, by the lack of scientific documentation of motion sickness occurrence among video game users. Although some published work (Cobb, 1999; Cobb and Nichols, 1998) showed that users of video game tend to develop some symptoms of motion sickness, there was no clear indication whether these subjects in fact experienced motion sickness. In this work, I argue that this uncertainty can be answered by simply asking the subjects whether they experience motion sickness throughout their virtual reality exposure, instead of only measuring the variation in terms of sickness symptoms score. It is also important to stress that the published studies on motion sickness and video games mainly use simplified laboratory developed video games, rather than using the commercially available console video games. In addition, motion sickness is studied in laboratory settings rather than in more realistic conditions. Therefore, this work is intended to document the existence of motion sickness, in a realistic environment. I varied the game that participants played, their posture during game play (standing vs. sitting), and the technology through which games were presented (video monitor vs. head-mounted display). In addition, I sought to evaluate the postural instability theory of motion sickness in the context of video game use. I measured body motion during game play, and showed that motion sickness was preceded by changes in both the magnitude and dynamics of body movement. In this work, participants played standard console video games using an Xbox game system. The series of experiments conducted were published in two peer review articles. The first paper "Motion Sickness, Console Video Games, and Head-Mounted Displays" evaluated the nauseogenic properties of commercial console video games when presented through a head-mounted display. The work published in this paper was aimed at 1) determining whether commercial console video games might be associated with motion sickness, 2) understanding some of the factors that my influence the incidence of motion sickness when commercial console video games are presented via an Head Mounted Display as well as conventional video monitor, and 3) documenting participants' body movement during game play and to use these data to evaluate a prediction of the postural instability theory of motion sickness (Riccio & Stoffregen, 1991). Participants played standard console video games using Xbox game system. The game type (two Xbox games) and postural configuration (standing vs. sitting) were varied. Subjects played for up to 50 minutes and were asked to discontinue if they experience any symptoms of motion sickness. The results showed that sickness occurred in all conditions, but it was more common during standing. There was statistically significant difference in head motion between sick and well participants before the onset of motion sickness during seated play. The findings indicate that commercial console video game systems can be linked to motion sickness occurrence when presented via a head-mounted display and support the hypothesis that motion sickness is preceded by instability in the control of seated posture. Although the results point at a relationship between motion sickness and video game when the game is played using an HMD, addition work was needed to test this relationship in a more realistic circumstances. In the second paper, "Motion Sickness and Postural Sway in Console Video Games", the work was aimed at testing the hypothesis that 1) participants might develop motion sickness while playing "off-the-shelf" console video games and 2) postural motion would differ between sick and well participants, prior to the onset and motion sickness. Participants in this sequence of experiments played a game continuously for up to 50 minutes while standing or sitting. The distance to the display screen was varied. As result, motion sickness was observed across conditions. It ranged from 42% to 56%. During game play, head and torso motion differed between sick and well participants prior to the onset of subjective of motion sickness. The results from this work indicated that console video game carry significant risk of motion sickness, even when displayed on conventional video monitor. In conclusion, the present work has successfully documented the anecdotal relationship between motion sickness and video games. Sickness occurred in all conditions. The results indicate that commercial console video game systems can induce motion sickness when presented via a head-mounted display, and via conventional video monitor. The results support the hypothesis that motion sickness is preceded by instability in the control of seated posture.
Motor imagery retraining after stroke with virtual hands: an immersive sensorimotor rhythm-based brain-computer interface
(2013-06) Doud, Alexander James
The burden of stroke on the health care system at large and individual patients is profound, and current techniques for rehabilitation rely on the training and dedication of the rehabilitation specialist. Here we present an immersive, virtual reality environment for presenting feedback to subjects in the form of a set of virtual hands. By just imagining the use of the left or right hands, subjects could see movement in the virtual hands and learn to modulate their thoughts to control them. Allowing subjects task relevant motor feedback early could prove an effective means of early rehabilitation. The implications of this training are presented in 6 patients who had suffered cortical or basal ganglia stroke. Using the system described below, the subject's were able to achieve control accuracies of as high as 81% in a binary classification task and showed progression of skill in as little as three, two-hour experimental sessions.
Oneirogen. Encountering the Impossible: Transformation through Virtual Reality
(University of Minnesota, Department of Art, 2018) Fladeboe, Andrew M
Palpable Visualizations: Techniques For Creatively Designing Discernible and Accessible Visualizations Grounded In the Physical World
(2020-06) Johnson, Seth
This dissertation investigates techniques to leverage creative processes like sketching, sculpting, and design iteration to improve the discernibility and accessibility of immersive volumetric data visualizations. Discernible visualizations support a viewer's ability to make sense of complexities such as multi-dimensional climate or engineering simulation data. Accessible data visualization both supports the contribution of previously under-utilized design expertise (i.e. artist-accessible visualization design), and subsequently provides access for a broad audience to engage with data through an emphasis on human connection and support for a wide range of displays. Such visualizations aim to provide a palpable, data-driven experience for scientists, artists, and the public. Three early works are presented as a rationale for investigating Palpable Visualizations. Bento Box, an immersive visualization system for comparing multiple time-varying volumetric simulation ensemble instances, demonstrates a current state-of-the-art for scientific data visualization. Weather Report, an interactive site-specific artwork visualizing six decades of weather data, takes an in-depth look at what can be accomplished when designing data-driven experiences in close collaboration with professional designers. And Lift-Off, a VR-based modeling program designed for artists, shows how creative sketching in both the physical and virtual worlds can result in a more accessible environment for both scientific and design-oriented tasks. Based on observations from these three prior works, we present Artifact-Based Rendering (ABR), a framework of algorithms and processes that makes it possible to produce real, data-driven 3D scientific visualizations with a visual language derived entirely from colors, lines, textures, and forms created using traditional physical media or found in nature. ABR addresses three current needs: (i) designing better visualizations by making it accessible for non-programmers to rapidly design and critique many alternative data-to-visual mappings; (ii) expanding the visual vocabulary used in scientific visualizations to enable discernment of increasingly complex multivariate data; (iii) bringing a more engaging, natural, and human-relatable handcrafted aesthetic to data visualization to make the resulting data-driven images more accessible and discernible to the viewer. Finally, we support the accessibility of visualizations through a data streaming and remote rendering pipeline, culminating in demonstrations bridging live supercomputer simulation data with untethered affordable head-mounted AR/VR displays.
Perceived Restoration of Hotel Lobbies: An Examination of Biophilic Design Attribute Organized Complexity and Attention Restoration Theory
(2019-12) Bilgic, Naz
Previous researchers have shown that a sense of connection with nature can improve human health and well-being. Attention Restoration Theory (ART) frequently uses immersion in natural or nature-inspired environments as a means of helping people recover from mental fatigue, stress, and exhaustion. Simultaneously, biophilic design has become increasingly influential in design fields, and has been associated with a wide array of benefits in human performance, health outcomes, and quality of life. Some design principles that are promoted in the biophilic design literature, such as the use of natural light, have been strongly supported by empirical research findings. Other components of biophilic design, however, particularly those related to more abstract elements and indirect invocations of nature, have received less empirical study. The current research focused on the principle of “organized complexity” as it is advocated in the biophilic design literature. An interior design based around the principle of organized complexity was created for a hotel lobby, a vital service-industry context that has not received much attention in biophilic design research compared to other settings such as healthcare and retail. Three different designs were created for the hotel lobby, each of which was very similar except for the level of organized complexity. For example, identical carpet patterns were used in each design, but the intricacy and size of the pattern was adjusted for low-, medium-, and high-complexity conditions. A randomized between-subject study was carried out by immersing participants in virtual-reality models of these designs, and obtaining and triangulating their fatigue-related and environmental preference responses on three survey instruments. Potential moderator variables were also considered, including gender, prior experience with virtual-reality, and prior experience working or studying in design professions. The results of the study did not show a statistically significant relationship between the objective organized complexity levels and attention restoration. However, the findings did indicate a positive relationship between perceived environmental complexity and attention restoration, as well as a correlation between self-reported environmental preferences and attention restoration. These findings appear to indicate that individual baselines and preferences are a crucial factor in the benefits associated with organized complexity in biophilic design. Further research will need to be carried out to confirm this result and to determine if any demographic patterns can be identified in these environmental preferences and benefits.
Scalable natural user interfaces for data-intensive exploratory visualization: designing in the context of big data
(2014-07) Coffey, Dane M.
This dissertation investigates new exploratory visualization tools in data-intensive domains that are built upon natural user interface technology, including multi-touch surfaces and virtual reality. Scalable interactions are developed and evaluated in several software systems that are targeted toward supporting design workflows that make use of big data. A new immersive and highly-interactive multi-touch workbench is presented, along with a theoretical framework and evaluation of how visualizations may be developed on it. Building upon this foundation, two different exploratory visualization software systems are presented that address distinct challenges faced by designers working in data-intensive domains. The first of these systems is called Slice World-In-Miniature (WIM), which is designed to overcome the difficulty associated with exploring large-volume data, where the complexity of the data often leads to the designers becoming disoriented. Using Overview+Detail techniques to provide context, the designer navigates inside of complex volumes using multi-touch gestures. This Slice WIM system is applied to a number of medical device design applications and evaluated by domain experts in this field. The second system is called Design by Dragging, which addresses the information overload associated with comparing and navigating many sets of interelated simulations. Design by Dragging gives the designer the power to explore high-dimensional simulation design spaces by using natural direct manipulation interactions. This system is applied to several problems in medical device design and in visual effects simulation, and a domain expert evaluation is presented. The big data paradigm is integrally tied to the future of computing. The major contribution of this dissertation is its investigation into the effectiveness of natural user interfaces as a means of working in this paradigm. Although natural user interfaces have become ubiquitous in our daily lives, they are typically used only for simple interactions. This dissertation demonstrates that these technologies can also be effective in aiding design work in the context of big data, a result that could shape the future of computing and change the way designers work with computers.
Seeing and Working with 3D Data in Virtual Reality
(2021-03) Kim, Kyungyoon
With recent advances in 3D data capturing technology and simulation, such as motion capture and laser scanning, a big portion of the data analysis process in many disciplines including medical, mechanical engineering, aerospace dynamics, involves examining and working with complex 3D data. Moving on from the traditional 2D keyboard-mouse environment, visualization researchers are seeing great benefits of utilizing the VR technologies to visualize 3D data. However, designing the VR environments to help users exploit these high quality data is challenging for multiple reasons. First, seeing (i.e. visualizing) 3D data requires careful considerations depending on the tasks and types or complexity of the data. Second, although 3D user interfaces theoretically provide great advantages for manipulating 3D data more directly and intuitively, working with 3D data has lack of precision compared to keyboard-mouse interfaces, for example a hand jitter and lack of haptic feedback to support the movements. Motivated by these challenges, this dissertation advances computational tools for seeing, for working, and for combining advanced seeing and working techniques together to enable interactive analyses of complex data. Advances to the science of data visualization address the hard problem of comparing multiple 3D and 4D datasets (i.e., comparative visualization), and include new theory (a taxonomy of fundamental approaches and survey of related work) as well as a real-world application to analyzing multiple phases of ancient architecture in VR. Advances to the science of 3D user interfaces address the long-standing problem of precise and accurate 3D object manipulation in virtual environments, including an application to improving 2D-3D shape matching, as needed in clinical medical imaging. The dissertation culminates by demonstrating that 3D data analyses that require advanced seeing and working simultaneously are, indeed, more challenging than when these tasks are performed in isolation, and that by putting and evaluating advanced visualizations and advanced interaction techniques together, we can help scientists to see and work with 3D data in virtual reality more effectively, differently, and with new perspectives.
Unity-based BCI2000 Application Layer: Virtual Reality and the Internet of Things
(2017-12) Coogan, Christopher
Brain-computer interfaces (BCIs) have enabled individuals to control devices such as spellers, robotic arms, drones, and wheelchairs, but often these BCI applications are restricted to research laboratories. With the advent of virtual reality (VR) systems and the internet of things (IoT) we can couple these technologies to offer real-time control of a user’s virtual and physical environment. Likewise, BCI applications are often single-use with user’s having no control outside of the restrictions placed upon the applications at the time of creation. Therefore, there is a need to create a tool that allows users the flexibility to create and modularize aspects of BCI applications for control of IoT devices and VR environments. Using a popular video game engine, Unity, and coupling it with BCI2000, we can create diverse applications that give the end-user additional autonomy during the task at hand. We demonstrate the validity of controlling a Unity-based VR environment and several commercial IoT devices via direct neural interfacing processed through BCI2000.
The virtual reality head-mounted display Oculus Rift induces motion sickness and is sexist in its effects
(2021-06) Munafo, Justin
Anecdotal reports suggest that motion sickness may occur among users of contemporary, consumer-oriented head-mounted display systems, and that women may be at greater risk. I evaluated the nauseogenic properties of one such system, the Oculus Rift. The head-mounted unit included motion sensors that were sensitive to users’ head movements, such that head movements could be used as control inputs to the device. In two experiments, seated participants played one of two virtual reality games for up to 15 minutes. In Experiment 1, 22% of participants reported motion sickness, and the difference in incidence between men and women was not significant. In Experiment 2, motion sickness was reported by 56% of participants, and incidence among women (77.78%) was significantly greater than among men (33.33%). Before participants were exposed to the head-mounted display system, I recorded their standing body sway during the performance of simple visual tasks. In both experiments, patterns of pre-exposure body sway differed between participants who (later) reported motion sickness and those who did not. In Experiment 2, sex differences in susceptibility to motion sickness were preceded by sex differences in body sway. These postural effects confirm a prediction of the postural instability theory of motion sickness. The results indicate that users of contemporary head-mounted display systems are at significant risk of motion sickness, and that in relation to motion sickness these systems may be sexist in their effects.
Virtual Reality Modeling of Patient Arterial Anatomy
(2020-04-19) Karlovich, Nick A.; Deakyne, Alex J.; Iaizzo, Paul A.
Virtual Reality (VR) is seeing wide use in many facets of industry and education. The medical field in particular has made advancements in visualization technology thanks to VR. In conjunction with 3-D modeling, VR has allowed for anatomical structures to be rendered in an immersive 3-D virtual space which can make for a more interactive and effective teaching tool. The Visible Heart® Laboratories (VHL) in the Department of Surgery at the University of Minnesotahas created a suite of VR software which can be used to assist in the design of medical devices, train future professionals, and educate users about anatomical features. A current obstacle of the platform is the user’s lack of experience in effectively navigating virtual environments; causing them to spend more time learning how to move through the anatomy instead of learning the anatomy itself. Here, we present new functionality to the VR platform that allows for an “on a rail” system which restricts the user’s movement to 1 spline of movement while still allowing a 360-viewing experience. This functionality drastically lowers the learning curve for navigating a virtual environment, enabling new users to focus on learning the anatomical features present in the scene. Specifically, the technology created here would be used to model a Transcatheter aortic valve replacement (TAVR) procedure which could be used to help train medical professionals and medical device innovators.

University Digital Conservancy

Browse by Subject

Browsing by Subject "Virtual Reality"