Many geoscience disciplines utilize complex computational models for advancing understanding and ... more Many geoscience disciplines utilize complex computational models for advancing understanding and sustainable management of Earth systems. Executing such models and their associated data preprocessing and postprocessing routines can be challenging for a number of reasons including (1) accessing and preprocessing the large volume and variety of data required by the model, (2) postprocessing large data collections generated by the model, and (3) orchestrating data processing tools, each with unique software dependencies, into workflows that can be easily reproduced and reused. To address these challenges, the work reported in this paper leverages the Workflow Structured Object functionality of the Integrated Rule‐Oriented Data System and demonstrates how it can be used to access distributed data, encapsulate hydrologic data processing as workflows, and federate with other community‐driven cyberinfrastructure systems. The approach is demonstrated for a study investigating the impact of ...
Since its introduction in 1994, Milgram and Kishino's reality-virtuality (RV) continuum has b... more Since its introduction in 1994, Milgram and Kishino's reality-virtuality (RV) continuum has been used to frame virtual and augmented reality research and development. While originally, the RV continuum and the three dimensions of the supporting taxonomy (extent of world knowledge, reproduction fidelity, and extent of presence metaphor) were intended to characterize the capabilities of visual display technology, researchers have embraced the RV continuum while largely ignoring the taxonomy. Considering the leaps in technology made over the last 25 years, revisiting the RV continuum and taxonomy is timely. In reexamining Milgram and Kishino's ideas, we realized, first, that the RV continuum is actually discontinuous; perfect virtual reality cannot be reached. Secondly, mixed reality is broader than previously believed, and, in fact, encompasses conventional virtual reality experiences. Finally, our revised taxonomy adds coherence, accounting for the role of users, which is cri...
We report on the design and results of an experiment investigating Slater's Place Illusion (P... more We report on the design and results of an experiment investigating Slater's Place Illusion (PI) and Plausibility Illusion (Psi) in a virtual visual cliff environment. Existing presence questionnaires could not reliably distinguish the effects of PI from those of Psi. They did, however, indicate that high levels of PI-eliciting characteristics and Psi-eliciting characteristics together result in higher presence, compared to any of the other three conditions. Also, participants' heart rates responded markedly differently in the two Psi conditions; no such difference was observed across the PI conditions.
Immersive Virtual Environments (VEs) enable user controlled interactions within the environment s... more Immersive Virtual Environments (VEs) enable user controlled interactions within the environment such as head-controlled point-of-view and user-controlled locomotion. In the real world people usually locomote by walking; walking is simple and natural, and enables people not only to move between locations, but also to develop cognitive maps, or mental representations, of environments. People navigate every day in the real world without problem, however users navigating VEs often become disoriented and frustrated, and find it challenging to transfer spatial knowledge acquired in the VE to the real world. In this dissertation I develop and demonstrate the effectiveness of a new locomotion interface, Redirected Free Exploration with Distractors (RFED) that enables people to freely walk in large scale VEs. RFED is the combination of distractors--objects, sounds, or combinations of objects and sounds in the VE that encourage people to turn their heads, and redirection--making the user turn...
IEEE transactions on visualization and computer graphics, Jan 25, 2017
We report on the design and results of an experiment investigating factors influencing Slater'... more We report on the design and results of an experiment investigating factors influencing Slater's Plausibility Illusion (Psi) in virtual environments (VEs). Slater proposed Psi and Place Illusion (PI) as orthogonal components of virtual experience which contribute to realistic response in a VE. PI corresponds to the traditional conception of presence as "being there," so there exists a substantial body of previous research relating to PI, but very little relating to Psi. We developed this experiment to investigate the components of plausibility illusion using subjective matching techniques similar to those used in color science. Twenty-one participants each experienced a scenario with the highest level of coherence (the extent to which a scenario matches user expectations and is internally consistent), then in eight different trials chose transitions from lower-coherence to higher-coherence scenarios with the goal of matching the level of Psi they felt in the highest-coh...
A fundamental task of an immersive virtual environment (IVE) system is to present images of the v... more A fundamental task of an immersive virtual environment (IVE) system is to present images of the virtual world that change appropriately as the user's head moves. Current IVE systems, especially those using head-mounted displays (HMDs), often produce spatially unstable scenes, resulting in simulator sickness, degraded task performance, degraded visual acuity, and breaks in presence. In HMDs, instability resulting from latency is greater than all other causes of instability combined. The primary way users perceive latency in an HMD is by improper motion of scenes that should be stationary in the world. Whereas latency-induced scene motion is well defined mathematically, less is understood about how much scene motion and/or latency can occur without subjects noticing, and how this varies under different conditions. I built a simulated HMD system with zero effective latency---no scene motion occurs due to latency. I intentionally and artificially inserted scene motion into the virtu...
extension of a user study performed at University College London in Mel Slater’s laboratory (Slat... more extension of a user study performed at University College London in Mel Slater’s laboratory (Slater, Usoh, & Steed, 1995). In 1998 we performed that study to evaluate how locomotion technique influences sense of presence (Usoh, 1999). That work was the first in a thread of research studies examining how a variety of technologies influence the effectiveness of virtual environments. This paper reports lessons the Effective Virtual Environments (EVE) research team learned while doing a dozen or more studies and lessons learned by another, cross-disciplinary team in the Distributed nanoManipulator project. In that project we designed, implemented, and evaluated a tool for distributed scientific collaboration (D. H. Sonnenwald, R. Berquist, K.
The incremental hardware costs of virtual locomotion are minimized when the technique uses intera... more The incremental hardware costs of virtual locomotion are minimized when the technique uses interaction capabilities available in controllers and devices that are already part of the VE system, e.g., gamepads, keyboards, and multi-function controllers. We used a different locomotion technique for each of these three devices: gamepad thumb-stick (joystick walking), a customized hybrid keyboard for gaming (speedpad walking), and an innovative technique that uses the orientation and triggers of the HTC Vive controllers (TriggerWalking). We explored the efficacy of locomotion techniques using these three devices in a hide and seek task in an indoor environment. We measured task performance, simulator sickness, system usability, perceived workload, and preference. We found that users had a strong preference for TriggerWalking, which also had the least increase in simulator sickness, the highest performance score, and highest perceived usability. However, participants using TriggerWalking ...
The presence construct, most commonly defined as the sense of “being there,” has driven research ... more The presence construct, most commonly defined as the sense of “being there,” has driven research and development of virtual environments (VEs) for decades. Despite that, there is not widespread agreement on how to define or operationalize this construct. The literature contains many different definitions of presence and many proposed measures for it. This article reviews many of the definitions, measures, and models of presence from the literature. We also review several related constructs, including social presence, copresence, immersion, agency, transportation, reality judgment, and embodiment. In addition, we present a meta-analysis of existing presence models and propose a model of presence informed by Slater’s Place Illusion and Plausibility Illusion constructs.
Proceedings of the 24th ACM Symposium on Virtual Reality Software and Technology, 2018
We report on the design and results of two experiments investigating Slater's Place Illusion ... more We report on the design and results of two experiments investigating Slater's Place Illusion (PI) and Plausibility Illusion (Psi) in a virtual visual cliff environment. PI (the illusion of being in a place) and Psi (the illusion that the depicted events are actually happening) were proposed by Slater as orthogonal components of virtual experience which contribute to realistic response in a VE. To that end, we identified characteristics of a virtual reality experience that we expected to influence one or the other of PI and Psi. We designed two experiments in which each participant experienced a given VE in one of four conditions chosen from a 2×2 design: high or low levels of PI-eliciting characteristics (that is, immersion) and high or low levels of Psi-eliciting characteristics. Following Skarbez, we use the term "coherence" for those characteristics which contribute to Psi, parallel to the use of "immersion" for characteristics that contribute to PI. We collected both questionnaire-based and physiological metrics. Several existing presence questionnaires could not reliably distinguish the effects of PI from those of Psi. They did, however, indicate that high levels of PI-eliciting characteristics and Psi-eliciting characteristics together result in higher presence, compared any of the other three conditions. This suggests that "breaks in PI" and "breaks in Psi" belong to a broader category of "breaks in experience," any of which result in a degraded user experience. Participants' heart rates, however, responded markedly differently in the two Psi conditions; no such difference was observed across the PI conditions. This indicates that a VE that exhibits unusual or confusing behavior can cause stress in a user that affects physiological responses, and that one must take care to eliminate such confusing behaviors if one is using physiological measurement as a proxy for subjective experience in a VE.
2018 10th International Conference on Virtual Worlds and Games for Serious Applications (VS-Games), 2018
Locomotion is one of the most basic interactions in virtual reality applications, and many techni... more Locomotion is one of the most basic interactions in virtual reality applications, and many techniques have been developed for moving in virtual environments. However, each technique works well in different scenarios, and is tested and evaluated in different test environments and on different tasks. To date, there has not been a common standard test bed which accommodates long, medium and short distance travel that would support testing and comparing locomotion techniques. This paper describes a novel testing environment for VR locomotion techniques, and explains the parameters that can be manipulated depending on the locomotion technique and the task. It also discusses the other possible attributes that can be included in future versions of the test environment.
Many geoscience disciplines utilize complex computational models for advancing understanding and ... more Many geoscience disciplines utilize complex computational models for advancing understanding and sustainable management of Earth systems. Executing such models and their associated data preprocessing and postprocessing routines can be challenging for a number of reasons including (1) accessing and preprocessing the large volume and variety of data required by the model, (2) postprocessing large data collections generated by the model, and (3) orchestrating data processing tools, each with unique software dependencies, into workflows that can be easily reproduced and reused. To address these challenges, the work reported in this paper leverages the Workflow Structured Object functionality of the Integrated Rule‐Oriented Data System and demonstrates how it can be used to access distributed data, encapsulate hydrologic data processing as workflows, and federate with other community‐driven cyberinfrastructure systems. The approach is demonstrated for a study investigating the impact of ...
Since its introduction in 1994, Milgram and Kishino's reality-virtuality (RV) continuum has b... more Since its introduction in 1994, Milgram and Kishino's reality-virtuality (RV) continuum has been used to frame virtual and augmented reality research and development. While originally, the RV continuum and the three dimensions of the supporting taxonomy (extent of world knowledge, reproduction fidelity, and extent of presence metaphor) were intended to characterize the capabilities of visual display technology, researchers have embraced the RV continuum while largely ignoring the taxonomy. Considering the leaps in technology made over the last 25 years, revisiting the RV continuum and taxonomy is timely. In reexamining Milgram and Kishino's ideas, we realized, first, that the RV continuum is actually discontinuous; perfect virtual reality cannot be reached. Secondly, mixed reality is broader than previously believed, and, in fact, encompasses conventional virtual reality experiences. Finally, our revised taxonomy adds coherence, accounting for the role of users, which is cri...
We report on the design and results of an experiment investigating Slater's Place Illusion (P... more We report on the design and results of an experiment investigating Slater's Place Illusion (PI) and Plausibility Illusion (Psi) in a virtual visual cliff environment. Existing presence questionnaires could not reliably distinguish the effects of PI from those of Psi. They did, however, indicate that high levels of PI-eliciting characteristics and Psi-eliciting characteristics together result in higher presence, compared to any of the other three conditions. Also, participants' heart rates responded markedly differently in the two Psi conditions; no such difference was observed across the PI conditions.
Immersive Virtual Environments (VEs) enable user controlled interactions within the environment s... more Immersive Virtual Environments (VEs) enable user controlled interactions within the environment such as head-controlled point-of-view and user-controlled locomotion. In the real world people usually locomote by walking; walking is simple and natural, and enables people not only to move between locations, but also to develop cognitive maps, or mental representations, of environments. People navigate every day in the real world without problem, however users navigating VEs often become disoriented and frustrated, and find it challenging to transfer spatial knowledge acquired in the VE to the real world. In this dissertation I develop and demonstrate the effectiveness of a new locomotion interface, Redirected Free Exploration with Distractors (RFED) that enables people to freely walk in large scale VEs. RFED is the combination of distractors--objects, sounds, or combinations of objects and sounds in the VE that encourage people to turn their heads, and redirection--making the user turn...
IEEE transactions on visualization and computer graphics, Jan 25, 2017
We report on the design and results of an experiment investigating factors influencing Slater'... more We report on the design and results of an experiment investigating factors influencing Slater's Plausibility Illusion (Psi) in virtual environments (VEs). Slater proposed Psi and Place Illusion (PI) as orthogonal components of virtual experience which contribute to realistic response in a VE. PI corresponds to the traditional conception of presence as "being there," so there exists a substantial body of previous research relating to PI, but very little relating to Psi. We developed this experiment to investigate the components of plausibility illusion using subjective matching techniques similar to those used in color science. Twenty-one participants each experienced a scenario with the highest level of coherence (the extent to which a scenario matches user expectations and is internally consistent), then in eight different trials chose transitions from lower-coherence to higher-coherence scenarios with the goal of matching the level of Psi they felt in the highest-coh...
A fundamental task of an immersive virtual environment (IVE) system is to present images of the v... more A fundamental task of an immersive virtual environment (IVE) system is to present images of the virtual world that change appropriately as the user's head moves. Current IVE systems, especially those using head-mounted displays (HMDs), often produce spatially unstable scenes, resulting in simulator sickness, degraded task performance, degraded visual acuity, and breaks in presence. In HMDs, instability resulting from latency is greater than all other causes of instability combined. The primary way users perceive latency in an HMD is by improper motion of scenes that should be stationary in the world. Whereas latency-induced scene motion is well defined mathematically, less is understood about how much scene motion and/or latency can occur without subjects noticing, and how this varies under different conditions. I built a simulated HMD system with zero effective latency---no scene motion occurs due to latency. I intentionally and artificially inserted scene motion into the virtu...
extension of a user study performed at University College London in Mel Slater’s laboratory (Slat... more extension of a user study performed at University College London in Mel Slater’s laboratory (Slater, Usoh, & Steed, 1995). In 1998 we performed that study to evaluate how locomotion technique influences sense of presence (Usoh, 1999). That work was the first in a thread of research studies examining how a variety of technologies influence the effectiveness of virtual environments. This paper reports lessons the Effective Virtual Environments (EVE) research team learned while doing a dozen or more studies and lessons learned by another, cross-disciplinary team in the Distributed nanoManipulator project. In that project we designed, implemented, and evaluated a tool for distributed scientific collaboration (D. H. Sonnenwald, R. Berquist, K.
The incremental hardware costs of virtual locomotion are minimized when the technique uses intera... more The incremental hardware costs of virtual locomotion are minimized when the technique uses interaction capabilities available in controllers and devices that are already part of the VE system, e.g., gamepads, keyboards, and multi-function controllers. We used a different locomotion technique for each of these three devices: gamepad thumb-stick (joystick walking), a customized hybrid keyboard for gaming (speedpad walking), and an innovative technique that uses the orientation and triggers of the HTC Vive controllers (TriggerWalking). We explored the efficacy of locomotion techniques using these three devices in a hide and seek task in an indoor environment. We measured task performance, simulator sickness, system usability, perceived workload, and preference. We found that users had a strong preference for TriggerWalking, which also had the least increase in simulator sickness, the highest performance score, and highest perceived usability. However, participants using TriggerWalking ...
The presence construct, most commonly defined as the sense of “being there,” has driven research ... more The presence construct, most commonly defined as the sense of “being there,” has driven research and development of virtual environments (VEs) for decades. Despite that, there is not widespread agreement on how to define or operationalize this construct. The literature contains many different definitions of presence and many proposed measures for it. This article reviews many of the definitions, measures, and models of presence from the literature. We also review several related constructs, including social presence, copresence, immersion, agency, transportation, reality judgment, and embodiment. In addition, we present a meta-analysis of existing presence models and propose a model of presence informed by Slater’s Place Illusion and Plausibility Illusion constructs.
Proceedings of the 24th ACM Symposium on Virtual Reality Software and Technology, 2018
We report on the design and results of two experiments investigating Slater's Place Illusion ... more We report on the design and results of two experiments investigating Slater's Place Illusion (PI) and Plausibility Illusion (Psi) in a virtual visual cliff environment. PI (the illusion of being in a place) and Psi (the illusion that the depicted events are actually happening) were proposed by Slater as orthogonal components of virtual experience which contribute to realistic response in a VE. To that end, we identified characteristics of a virtual reality experience that we expected to influence one or the other of PI and Psi. We designed two experiments in which each participant experienced a given VE in one of four conditions chosen from a 2×2 design: high or low levels of PI-eliciting characteristics (that is, immersion) and high or low levels of Psi-eliciting characteristics. Following Skarbez, we use the term "coherence" for those characteristics which contribute to Psi, parallel to the use of "immersion" for characteristics that contribute to PI. We collected both questionnaire-based and physiological metrics. Several existing presence questionnaires could not reliably distinguish the effects of PI from those of Psi. They did, however, indicate that high levels of PI-eliciting characteristics and Psi-eliciting characteristics together result in higher presence, compared any of the other three conditions. This suggests that "breaks in PI" and "breaks in Psi" belong to a broader category of "breaks in experience," any of which result in a degraded user experience. Participants' heart rates, however, responded markedly differently in the two Psi conditions; no such difference was observed across the PI conditions. This indicates that a VE that exhibits unusual or confusing behavior can cause stress in a user that affects physiological responses, and that one must take care to eliminate such confusing behaviors if one is using physiological measurement as a proxy for subjective experience in a VE.
2018 10th International Conference on Virtual Worlds and Games for Serious Applications (VS-Games), 2018
Locomotion is one of the most basic interactions in virtual reality applications, and many techni... more Locomotion is one of the most basic interactions in virtual reality applications, and many techniques have been developed for moving in virtual environments. However, each technique works well in different scenarios, and is tested and evaluated in different test environments and on different tasks. To date, there has not been a common standard test bed which accommodates long, medium and short distance travel that would support testing and comparing locomotion techniques. This paper describes a novel testing environment for VR locomotion techniques, and explains the parameters that can be manipulated depending on the locomotion technique and the task. It also discusses the other possible attributes that can be included in future versions of the test environment.
Uploads
Papers by Mary Whitton