bluuebunny/crossref_metadata_2025 huggingface dataset:
Three Dimensional Visual Display Systems for Virtual Environments
Authors: McKenna Michael , Zeltzer David
Published: December 2015

This paper surveys three-dimensional (3D) visual display technology as it relates to realtime, interactive systems—or virtual environment systems. Five major 3D display types are examined: stereoscopic, lenticular, parallax barrier, slice-stacking, and holographic displays. The major characteristics of each display type are examined, i.e. spatial resolution, depth resolution, field of view, viewing zone, bandwidth, etc. In addition, the corresponding parameters of the human visual systems are described. The different display systems, as well as the human visual system, are compared in tabular form.
Integrating Graphic and Audio Windows
Authors: Cohen Michael
Published: December 2015

It is important to exploit sound as a vital communication channel for computer-human interfaces. Developing this potential motivates both developing expressive models unique to audio and also exploring analogues to visual modes of representation. This paper elaborates an organization of presentation and control that implements a flexible sound management system called “audio windows.” After reviewing audio imaging, spatial sound, and relevant underlying technology, an audio windowing prototype is described, implementing an extended model of free-field, two-dimensional spatial sound control. The system, “Maw” (acronymic for multidimensional audio windows), is a GUI (graphic user interface), integrating a graphic editor with a multidimensional spatial sound engine. Standard idioms for WIMP (window, icon, menu, pointing device) systems are reinterpreted for audio window applications, including provisions for directionalized and nonatomic spatial sound objects. Unique features include draggably rotating icons, clusters, dynamically collapsible hierarchical groups of spatial sound objects, and an autofocus mode that is used to disambiguate multiple presence.
Dramatic Presence
Authors: Kelso Margaret Thomas , Weyhrauch Peter , Bates Joseph
Published: December 2015

Let us consider the presentation by computers of rich, highly interactive worlds that are inhabited by dynamic and complex characters, and shaped by aesthetically pleasing stories. We shall call this interactive drama, and we believe that it requires strong characters, aesthetic presentation, and long-term dramatic structure. This paper describes an experiment designed to help us understand how to create interactive drama. Three principal questions are addressed. One, how does it feel to be immersed in a dramatic virtual world filled with characters and story? Two, what is required of the characters (actors) in such a virtual world? Three, what is required of the story and its director? We present an introduction to interactive drama, summarize the Oz system designed to create and present such experiences, and describe our experiment in detail. Finally, drawing from the experiment, we suggest several hypotheses about interactive drama.
Estimating Three-Dimensional Space from Multiple Two-Dimensional Views
Authors: Thorisson Kristinn R.
Published: December 2015

The most common visual feedback technique in teleoperation is in the form of monoscopic video displays. As robotic autonomy increases and the human operator takes on the role of a supervisor, three-dimensional information is effectively presented by multiple, televised, two-dimensional (2-D) projections showing the same scene from different angles. To analyze how people go about using such segmented information for estimations about three-dimensional (3-D) space, 18 subjects were asked to determine the position of a stationary pointer in space; eye movements and reaction times (RTs) were recorded during a period when either two or three 2-D views were presented simultaneously, each showing the same scene from a different angle. The results revealed that subjects estimated 3-D space by using a simple algorithm of feature search. Eye movement analysis supported the conclusion that people can efficiently use multiple 2-D projections to make estimations about 3-D space without reconstructing the scene mentally in three dimensions. The major limiting factor on RT in such situations is the subjects' visual search performance, giving in this experiment a mean of 2270 msec (SD = 468; N = 18). This conclusion was supported by predictions of the Model Human Processor (Card, Moran, & Newell, 1983), which predicted a mean RT of 1820 msec given the general eye movement patterns observed. Single-subject analysis of the experimental data suggested further that in some cases people may base their judgments on a more elaborate 3-D mental model reconstructed from the available 2-D views. In such situations, RTs and visual search patterns closely resemble those found in the mental rotation paradigm (Just & Carpenter, 1976), giving RTs in the range of 5-10 sec.
A Shape Modeling System with a Volume Scanning Display and Multisensory Input Device
Authors: Kameyama Ken-ichi , Ohtomi Koichi
Published: December 2015

This paper describes a newly developed 3-D shape modeling system, in which a user can design a free-form surface as if he or she actually manipulates a flexible object made from rubber or clay. Such reality can be realized in the system without any encumbering devices like goggles, glasses, or gloves, which is impossible in conventional virtual reality systems. The system is composed of a volume scanning display for presenting a surface image in a real 3-D space, a multisensory input device for detecting the force for deformation, and a half-silvered mirror for spatial superposition of the image onto the input device. A user can directly manipulate a free-form surface by virtually pushing the image, actually pushing the input device, and at the same time, he or she can feel the input device resist its actual deformation as the resisting force of the virtual surface. The system has several types of deforming models, and two types of free-form surfaces that have different curvatures have been experimentally created.
Supernormal Auditory LocalizationI. General Background
Authors: Durlach N.I. , Shinn-Cunningham B.G. , Held R.M.
Published: December 2015

In this series of papers, we consider human auditory localization and how its deficiencies can be reduced by appropriate processing and coding of acoustical signals in teleoperator and virtual-environment systems. Attention is given to how localization cues can be altered to improve the just-noticeable-difference (JND) in spatial position and to phenomena related to the use of such altered localization cues for the identification of spatial position. Unlike most current studies of synthetic auditory localization, our study includes consideration of distance as well as direction. In this first paper of the series, we provide general background material. In subsequent papers, we will present a variety of empirical results.
Calibrating the Human Hand for Haptic Interfaces
Authors: Rohling Robert N. , Hollerbach John M.
Published: December 2015

Determination of human hand poses from hand master measurements of joint angles requires an accurate human hand model for each operator. A new method for human hand calibration is proposed, based on open-loop kinematic calibration. The parameters of a kinematic model of the human index finger are determined as an example. Singular value decomposition is used as a tool for analyzing the kinematic model and the identification process. It was found that accurate and reliable results are obtained only when the numerical condition is minimized through parameter scaling, model reduction and pose set selection. The identified kinematic parameters of the index finger with the Utah Dextrous Hand Master show that the kinematic model and the calibration procedure have an accuracy of about 2 mm.
Sensory Substitution for Force Feedback in Teleoperation
Authors: Massimino Michael J. , Sheridan Thomas B.
Published: December 2015

The objective of this research was to study the capabilities of sensory substitution for force feedback through the tactile and auditory senses for teleoperation tasks, with and without time delay. The motivation and potential benefits of sensory substitution for force feedback with vibrotactile and auditory displays are discussed. Teleoperator experiments that examined the presentation of basic force information through object contact tasks indicated that operator performance was improved by using the vibrotactile and auditory displays to present force information. Further, the vibrotactile and auditory displays compared favorably to traditional bilateral force feedback. Common manipulation experiments with peg-in-hole tasks of varying complexity were also conducted and showed that when the subjects' view was fully obstructed, the subjects were able to successfully complete the task by using either of the sensory substitution displays. Sensory substitution was also tested in the presence of a 3 sec time delay and significantly improved performance without instabilities.
The VEOS Project
Authors: Bricken William , Coco Geoffrey
Published: December 2015

The Virtual Environment Operating Shell (veos) was developed at University of Washington's Human Interface Technology Laboratory as software infrastructure for the lab's research in virtual environments. veos was designed from scratch to provide a comprehensive and unified management facility to support generation of, interaction with, and maintenance of virtual environments. VEOS emphasizes rapid prototyping, heterogeneous distributed computing, and portability. We discuss the design, philosophy and implementation of veos in depth. Within the Kernel, the shared database transformations are pattern-directed, communications are asynchronous, and the programmer's interface is LISP. An entity-based metaphor extends object-oriented programming to systems-oriented programming. Entities provide first-class environments and biological programming constructs such as perceive, react, and persist. The organization, structure, and programming of entities are discussed in detail. The article concludes with a description of the applications that have contributed to the iterative refinement of the VEOS software.
Sliding Control of Force Reflecting Teleoperation:Preliminary Studies
Authors: Buttolo Pietro , Braathen Petter , Hannaford Blake
Published: December 2015

In this paper, sliding mode nonlinear control is applied to force reflecting teleoperation. Various forms of the sliding mode control law are derived for force feedback master manipulation with an arbitrary factor for force and position scaling. Experiments were performed on a one axis test system and frequency domain Hybrid 2-port matrices are measured and compared between the sliding mode controller and a classical position error-based feedback controller. Time domain experiments are also performed. The model-based portion of the sliding mode controller was shown to be responsible for most of its performance improvement, but the nonlinear “sliding” component was essential for steady-state position accuracy and robust stability.
Virtual Worlds as Fuzzy Cognitive Maps
Authors: Dickerson Julie A. , Kosko Bart
Published: December 2015

Fuzzy cognitive maps (FCM) can structure virtual worlds that change with time. An FCM links causal events, actors, values, goals, and trends in a fuzzy feedback dynamical system. An FCM lists the fuzzy rules or causal flow paths that relate events. It can guide actors in a virtual world as the actors move through a web of cause and effect and react to events and to other actors. Experts draw FCM causal pictures of the virtual world. They do not write down differential equations to change the virtual world. Complex FCMs can give virtual worlds with “new” or chaotic equilibrium behavior. Simple FCMs give virtual worlds with periodic behavior. They map input states to limit-cycle equilibria. An FCM limit cycle repeats a sequence of events or a chain of actions and responses. Limit cycles can control the steady-state rhythms and patterns in a virtual world. In nested FCMs each causal concept can control its own FCM or fuzzy function approximator. This gives levels of fuzzy systems that can choose goals and causal webs as well as move objects and guide actors in the webs. FCM matrices sum to give a combined FCM virtual world for any number of knowledge sources. Adaptive FCMs change their fuzzy causal web as causal patterns change and as actors act and experts state their causal knowledge. Neural learning laws change the causal rules and the limit cycles. Actors learn new patterns and reinforce old ones. In complex FCMs the user can choose the dynamical structure of the virtual world from a spectrum that ranges from mildly to wildly nonlinear. We use a simple but adaptive FCM to model an undersea virtual world of dolphins, fish, and sharks.
Use of a Two-Class Model to Analyze Applications and Barriers to the Use of Virtual Reality by People with Disabilities
Authors: Vanderheiden Gregg C. , Mendenhall John
Published: December 2015

In analyzing virtual reality applications to examine access issues for people with disabilities, it is useful to separate those applications where the virtual reality (VR) presentation is used as a metaphor from those where the mode of presentation is inherently tied to, or restricted by, the information being presented. In the case where VR is being used only as a metaphor, it is often possible to provide access even to individuals with severe physical, cognitive, and sensory impairments by providing a display/control via an alternate mechanism in parallel with the VR metaphor. This type of parallel display/control strategy is not available when the presentation is inherently tied to the information being presented. For both types of applications, however, the application of virtual altered realities (VAR) can be used to either transpose or enhance the presentation of information in order to facilitate its perception and manipulation by people with varying physical, cognitive, and sensory abilities. This paper presents the strategies underlying these two approaches as well as providing examples of ways the strategies can be used to increase the accessibility and useability of virtual reality by people with disabilities.
The Enhancement of Interaction for People with Severe Speech and Physical Impairment through the Computer Recognition of Gesture and Manipulation
Authors: Roy David M. , Panayi Marilyn , Foulds Richard , Erenshteyn Roman , Harwin William S. , Fawcus Robert
Published: December 2015

The research involves using drama and mime to elicit Intentional behaviors such as gesture and manipulation from people who cannot access a keyboard directly due to severe speech and physical impairment due to cerebral palsy. Although the resulting movements are often imprecise and idiosyncratic, attempts are being made to recognize them by computer. Sensors are being used to monitor continuous signals from the body. Feature extraction and classification techniques involving artificial neural networks are being developed to recognize intention. As part of an early intervention strategy, the system could create the opportunity for children with disabilities to learn through physical interaction and exploration. It is envisioned that the final system could be used to facilitate interaction with a selection of multisensory real and virtual worlds.
The Visual Display Transformation for Virtual Reality
Authors: Robinett Warren , Holloway Richard
Published: December 2015

The visual display transformation for virtual reality (VR) systems is typically much more complex than the standard viewing transformation discussed in the literature for conventional computer graphics. The process can be represented as a series of transformations, some of which contain parameters that must match the physical configuration of the system hardware and the user's body. Because of the number and complexity of the transformations, a systematic approach and a thorough understanding of the mathematical models involved are essential. This paper presents a complete model for the visual display transformation for a VR system; that is, the series of transformations used to map points from object coordinates to screen coordinates. Virtual objects are typically defined in an object-centered coordinate system (CS), but must be displayed using the screen-centered CSs of the two screens of a head-mounted display (HMD). This particular algorithm for the VR display computation allows multiple users to independently change position, orientation, and scale within the virtual world, allows users to pick up and move virtual objects, uses the measurements from a head tracker to immerse the user in the virtual world, provides an adjustable eye separation for generating two stereoscopic images, uses the off-center perspective projection required by many HMDs, and compensates for the optical distortion introduced by the lenses in an HMD. The implementation of this framework as the core of the UNC VR software is described, and the values of the UNC display parameters are given. We also introduce the vector-quaternion-scalar (VQS) representation for transformations between 3D coordinate systems, which is specifically tailored to the needs of a VR system. The transformations and CSs presented comprise a complete framework for generating the computer-graphic imagery required in a typical VR system. The model presented here is deliberately abstract in order to be general purpose; thus, issues of system design and visual perception are not addressed. While the mathematical techniques involved are already well known, there are enough parameters and pitfalls that a detailed description of the entire process should be a useful tool for someone interested in implementing a VR system.
Towards Quantifying Depth and Size Perception in Virtual Environments
Authors: Rolland Jannick P. , Gibson William , Ariely Dan
Published: December 2015

With the rapid advance of real-time computer graphics, head-mounted displays (HMDs) have become popular tools for 3D visualization. One of the most promising and challenging future uses of HMDs, however, is in applications where virtual environments enhance rather than replace real environments. In such applications, a virtual image is superimposed on a real image. The unique problem raised by this superimposition is the difficulty that the human visual system may have in integrating information from these two environments. As a starting point to studying the problem of information integration in see-through environments, we investigate the quantification of depth and size perception of virtual objects relative to real objects in combined real and virtual environments. This starting point leads directly to the important issue of system calibration, which must be completed before perceived depth and sizes are measured. Finally, preliminary experimental results on the perceived depth of spatially nonoverlapping real and virtual objects are presented.
Lag in Multiprocessor Virtual Reality
Authors: Wloka Matthias M.
Published: December 2015

Lag in virtual reality (VR), i.e., the delay between performing an action and seeing the result of that action, is critical when trying to achieve immersion. While multiple, networked processors have been used to increase throughput, we concentrate on using multiple processors to reduce lag. To that end, we present a complete list of all possible lag sources in VR applications, review available lag reduction techniques, and investigate how these reduction techniques interrelate. We also introduce a new process-synchronization scheme that reduces lag. We evaluate the effectiveness of this synchronization scheme by software simulation as well as by actual lag measurements in our sample application.
The Representation of Experience in Architectural Design
Authors: Zobel Richard W.
Published: December 2015

Architecture, which is by its very nature a three-dimensional art, has in the last 500 years evolved to a stage where nearly all of the design exploration and visualization occur in any of a number of two-dimensional media. These media do not effectively portray the experiential quality of approaching, entering, and moving through an architectural space, an aspect which is primary to any design. In discussing this, James J. Gibson's concept of affordance will be used as a basis for the examination of a variety of media that are commonly used to describe the experiential quality of architecture, and how each of these media speaks to this frequently neglected characteristic. Particular attention will be given to the new technology of computer-generated immersive environments, which as a design medium promises to bring the issue of experiential quality in architecture to the forefront of design. Examples of each of the most common media, physical models, perspectives, noninteractive screen-based architectural walk throughs, interactive screen-based architectural walk throughs, and computer-generated immersive environments, will be examined as to their utility in experiential description. A discussion of the specific characteristics of each of the electronic media and the applications benefits and drawbacks will be included.
Toward Virtual Reality in Architecture:Concepts and Scenarios from the Architectural Space Laboratory
Authors: Schmitt Gerhard , Wenz Florian , Kurmann David , Mark Eric van der
Published: December 2015

Virtual reality is the logical step that started way back in time with the appearance of the very first architectural drawing. This has been a long history of development: architectural drawings in Europe, which date back to the tenth century, were the first kind of abstraction that appeared “virtually real” to potential clients and builders—real enough to base decisions on. With the discovery of perspective techniques, drawings became more refined and developed into a form of art with numerous branches, ranging from technical drawings to presentation drawings. Wooden models appeared even before the Renaissance and were supplemented in the nineteenth century with cardboard models. Each new invention helped to improve the understanding of projects and architecture by reducing abstraction, while increasing the complexity of the representation (Schmitt, 1993). Toward the end of the twentieth century, the majority of architectural projects were and are never realized. Prominent projects, such as the new Berlin Government Centre, result in several hundred professional competition entries. With the advent of virtual reality (VR) techniques, architects will at first intensely criticise the new technology, before adopting and improving it, and they will modify it with domain specific contributions. The knowledge of architectural abstraction and simulation is useful to the further development of VR and vice versa. Today, the newest methodological and technical instruments help designers to create a more responsible architecture, many aspects of which can be experienced and tested before construction. This includes the possibility of expanding the number of senses addressed for the explanation of an architectural idea. To structure the discussion about VR in architecture, we first describe the theoretical framework, then move to the description of a Architectural Space Laboratory at the Architecture Department of the Swiss Federal Institute of Technology, ETH Zürich, and follow this with examples of program development. We conclude with speculations on the impact of the new technology on the architecture of the future.
Manufacturing Operations in Virtual Environments (MOVE)
Authors: Wilson John R. , Brown David J. , Cobb Susan V. , D'Cruz Mirabelle M. , Eastgate Richard M.
Published: December 2015

During the past 2 years, the way in which industry views virtual reality (VR) has changed. Previously, only a few large companies were assessing virtual environments either as “internal marketing exercises” or through demonstration worlds built for them by outside consultants or universities; most other industrialists may have seen VR as only having entertainment applications. Now there is some evidence that parts of industry, and manufacturing industry in particular, see VR as an increasingly affordable technology with potentially wide-ranging applications. This paper briefly describes a recent U.K. research program MOVE (Manufacturing Operations in Virtual Environments) consisting of an industrial VR user survey and demonstration applications built to allow potential users to make informed assessments of virtual environments. Two particular applications—training for maintenance and rapid prototyping for product design—are described in greater detail as examples of industrially relevant environments, before an assessment is provided of potential VR application in manufacturing.
Networked Virtual Reality and Cooperative Work
Authors: Benford Steve , Bowers John , Fahlén Lennart E. , Greenhalgh Chris , Mariani John , Rodden Tom
Published: December 2015

We explore the issue of supporting cooperative work using networked virtual reality. This exploration covers three major themes: supporting communication and awareness, structuring space, and embodying users. Correspondingly, three sets of concepts are introduced. The first is a spatial model of interaction, which defines the mechanisms of aura, awareness, focus, nimbus, and adapters to allow the inhabitants of virtual environments to flexibly manage their communication across a number of media. The second is a set of techniques for constructing Populated Information Terrains (PITS), abstract data spaces that support the cooperative browsing of information. The third is a set of design issues for virtual bodies. Each set of concepts is illustrated with a discussion of prototype applications implemented within our own DIVE and MASSIVE networked virtual reality systems.
Methods to Calibrate Projection Transformation Parameters for See-Through Head-Mounted Displays
Authors: Oishi Takashi , Tachi Susumu
Published: December 2015

See-through head-mounted displays (STHMDs), which superimpose the virtual environment generated by computer graphics (CG) on the real world, are expected to be able to vividly display various simulations and designs by using both the real environment and the virtual environment around us. However, we must ensure that the virtual environment is superimposed exactly on the real environment because both environments are visible. Disagreement in matching locations and size between real and virtual objects is likely to occur between the world coordinates of the real environment where the STHMD user actually exists and those of the virtual environment described as parameters of CG. This disagreement directly causes displacement of locations where virtual objects are superimposed. The STHMD must be calibrated so that the virtual environment is superimposed properly. Among the causes of such errors, we focus both on systematic errors of projection transformation parameters caused in manufacturing and differences between actual and supposed location of user's eye on STHMD when in use, and propose a calibration method to eliminate these effects. In the calibration method, the virtual cursor drawn in the virtual environment is directly fitted onto targets in the real environment. Based on the result of fitting, the least-squares method identifies values of the parameters that minimize differences between locations of the virtual cursor in the virtual environment and targets in the real environment. After we describe the calibration methods, we also report the result of this application to the STHMD that we have made. The result is accurate enough to prove the effectiveness of the calibration methods.
Large Models for Virtual Environments: A Review of Work by the Architectural Walkthrough Project at UNC
Authors: Mine Mark R. , Weber Hans
Published: December 2015

Oth law of model dynamics: In a finite (and usually very short) amount of time, users of a graphics system will generate a model that shall bring said system to its knees.

The purpose of this paper is to discuss our experiences with the impact of megamodels on interactive virtual environments. We consider a megamodel to be any model that causes the Oth law of model dynamics to come into effect. We will demonstrate how working with megamodels quickly reveals the limitations of the graphics hardware and software being used to support the virtual environment. We will give examples, based upon our experiences on the Architectural Walkthrough Project here at the University of North Carolina at Chapel Hill (UNC), of the kinds of extra effort required to overcome these limitations.
Rapid Modeling and Design in Virtual Environments
Authors: Grinstein Georges G. , Southard David A.
Published: December 2015

We discuss the evolution and current status of investigations at our Graphics, Visualization, and Virtual Environments Laboratory. The progression of user interface technology has led us from display systems evaluation, to performance studies of graphics workstations, stereoscopic and head-mounted displays, user-input devices, and interactive techniques for virtual environments. We have been involved in prototyping applications for terrain visualization, situation awareness for command and control, maintenance procedures training, and interactive design. Our current emphasis is on developing techniques for rapid modeling of virtual environments, to support mission planning, rehearsal, and interactive design and visualization. We discuss in detail three examples of these applications, and we present a set of guidelines that we have found to be useful for quickly constructing effective virtual environments.
Model-Based Supervisory Control in Telerobotics
Authors: Blackmon Theodore T. , Stark Lawrence W.
Published: December 2015

Model-based approaches can be used to confront several of the challenging performance issues in teleoperation. This paper describes a model-based supervisory control technique for telerobotics. A human-machine interface (HMI) was developed for online, interactive task segmentation and planning utilizing a world model of the telerobotic working environment (TRWE). The task model is transferred intermittently over a low bandwidth communication channel for interpretation, planning, and execution of the task segments through the autonomous control capabilities of a telerobot. For the purposes of outlining tasks, a human operator controls a simulation model to generate a “task sequence script” as a sequential list of desired sub-goals for a telerobot. A graphic user interface (GUI) facilitates the development of the task sequence script with viewing perspectives of the graphic display automatically selected as a function of the operational state and model parameters. Also, because the human operator is specifying discrete model set-points of the TRWE, and allowing the autonomous control capabilities of the telerobot to coordinate the actual trajectory between set-points, a provision is made to preview the proposed trajectory for approval or modification before execution. Preliminary results with a manipulator arm remotely controlled via the Internet demonstrate the utility of the model-based supervisory control technique.
Determining the Field of View in HMDs: A Psychophysical Method
Authors: Rinalducci Edward J. , Mapes Dan , Cinq-Mars Stephen G. , Higgins Kent E.
Published: December 2015

Rather than researchers having to rely on manufacturers' specifications or an optical or engineering analysis, this paper provides a psychophysical method for determining the horizontal and vertical field of view of an HMD system. The technique employed makes use of a strobe light induced afterimage of two lights that subtend a predetermined size. This after image can then be used to set the width of two bars in the virtual environment and the number of pixels between the bars can be determined. Simple equations are provided to allow a determination of the basic dimensions of the display.
Casualty Modeling for Real-Time Medical Training
Authors: Chi Diane M. , Clarke John R. , Webber Bonnie L. , Badler Norman I.
Published: December 2015

We present a model for simulating casualties in virtual environments for real-time medical training. It allows a user to choose diagnostic and therapeutic actions to carry out on a simulated casualty who will manifest appropriate physiological, behavioral, and physical responses. Currently, the user or a “stealth instructor” can specify one or more injuries that the casualty has sustained. The model responds by continuously determining the state of the casualty, responding appropriately to medical assessment and treatment procedures. So far, we have modeled four medical conditions and over 20 procedures. The model has been designed to handle the addition of other injuries and medical procedures.
VRLOCO: Real-Time Human Locomotion from Positional Input Streams
Authors: Ko Hyeongseok , Cremer James
Published: December 2015

Virtual reality applications, especially in entertainment and training, require environments populated with multiple interacting humans. Whether the virtual humans are controlled by real people or by computer programs, a large portion of their activity will involve locomotion. This paper presents VRLOCO, a “locomotion engine” designed to meet the locomotion requirements of virtual environments. First, VRLOCO is broadly capable; it includes five locomotion primitives—walking, running, lateral stepping, turning around, and backward stepping—and can blend smoothly between primitives during transitions. Second, locomotion control in VRLOCO is simple; controllers drive the locomotion by supplying streams of intuitive positional inputs—desired body center position and facing direction—over time. Finally, VRLOCO is responsive and efficient; it generates locomotion on-line, processing user- or program-generated control inputs and producing new frames at rates greater than 30 Hz. Technically, VRLOCO combines a method for generalizing prototypical locomotion data with algorithms for determining locomotion mode and blending between different modes. The effectiveness of the approach has been tested using several locomotion controllers—programs representing autonomous agents, interactive graphic user interfaces, and a VR input device consisting of a stationary bicycle equipped with optical encoders and a microcontroller.
The Virtual Environment for Body-Image Modification (VEBIM): Development and Preliminary Evaluation
Authors: Riva Giuseppe
Published: December 2015

The Virtual Environment for Body Image Modification (VEBIM) is a set of tasks aimed at treating body-image disturbances and body dissatisfation associated with eating disorders. Two methods are commonly used to treat body-image disturbance: (1) a cognitive-behavioral therapy to influence patients' feelings of dissatisfaction and (2) a visual-motorial therapy, with the aim of influencing the level of bodily awareness. VEBIM tries to integrate these two therapeutical approaches within an immersive virtual environment. The choice of VEBIM would not only make it possible to intervene simultaneously on all of the forms of bodily representations but also to use for therapeutical purposes the psychophysiological effects provoked on the body by the virtual experience. The paper describes the VEBIM theoretical approach and its characteristics; it also presents a study on a preliminary sample (72 normal subjects) to test the efficacy of this approach.
The Effectiveness of Virtual Reality for Administering Spatial Navigation Training to Firefighters
Authors: Bliss James P. , Tidwell Philip D. , Guest Michael A.
Published: December 2015

Because fire rescue personnel often enter unfamiliar buildings to perform critical tasks like rescues, the importance of finding new and improved ways to train route navigation is becoming paramount. This research was designed to compare three methods for training firefighters to navigate a rescue route in an unfamiliar building. Thirty firefighters from the Madison County, Alabama, area were trained to navigate through the Administrative Science Building at The University of Alabama in Huntsville. The firefighters, who had not had any experience with the Administrative Science Building prior to the experiment, were randomly assigned to one of three experimental training groups: Blueprint, Virtual Reality, or No Training (Control). After training, we measured the total navigation time and number of wrong turns exhibited by firefighters in the actual building. Participants were required to rescue a mock baby (a life-sized doll) following the specific trained route. Measures of test performance were compared among groups by using analyses of variance (ANOVAs). The results indicated that firefighters trained with virtual reality or blueprints performed a quicker and more accurate rescue than those without training. Furthermore, the speed and accuracy of rescue performance did not differ significantly between virtual reality and blueprint training groups. These results indicate that virtual reality training, if constructed and implemented properly, may provide an effective alternative to current navigation training methods. The results are discussed with regard to theories of transfer of training and human performance in virtual environments.
Virtual Environments for Medical Training and Education
Authors: Satava Richard M. , Jones Shaun B.
Published: December 2015

There are a number of modalities for implementing Virtual Environments (VE) for medical training and simulation. Integrating them for a seamless transition from one to another presents the next challenge. The three applications of (1) individual anatomic education and training, (2) medical crisis planning and training, and (3) medical virtual prototyping have been integrated into a single program approach by the military for battlefield trauma care. With this model as a template, the power of VE for the many different aspects of medical education can be explored and exploited.
New Simulation Technologies for Surgical Training and Certification: Current Status and Future Projections
Authors: Higgins Gerald A. , Merrill Gregory L. , Hettinger Lawrence J. , Kaufmann Christoph R. , Champion Howard R. , Satava Richard M.
Published: December 2015

Computer-based virtual reality technology has evolved to the point at which medical simulation can be incorporated into medical education and into the eventual objective evaluation of surgical competence. Flight simulation provides a model for examining the role of computer-based simulation in medical training and certification. The plan by which medical simulators are being designed and validated for surgical training is presented, as is a description of the current state of medical simulation and the limitations of the technology. A realistic argument for adoption is suggested that takes into account lower price constraints, technological limitations, and professional barriers to the implementation of simulator-based training and accreditation.1
Virtual Endoscopy: Application of 3D Visualization to Medical Diagnosis
Authors: Satava Richard M. , Robb Richard A.
Published: December 2015

Virtual endoscopy is a diagnostic technique in which a three-dimensional imaging technology (CT scan, MRI scan, ultrasound) is used to create a computer-generated representation of a specific patient's anatomy or organ, and then the virtual organ is “flown through,” giving the same visual impression and image as if the corresponding real organ had a video or fiberoptic endoscopic procedure performed. The potential is to provide a computer diagnosis to replace an endoscopic procedure, not only for conventional endoscopy such as bronchoscopy, colonoscopy, sinusoscopy, or hysteroscopy, but also for areas where traditional endoscopy is not possible, such as the inner ear, spleen, lymphatic tissues. With sophisticated signal processing and computational analysis, it may be possible in the future to perform a “numerical biopsy,” that is, make a tissue diagnosis based upon spectral or other information contained in the images.
Computer Vision-Based Augmented Reality for Guiding Manual Assembly
Authors: Sharma Rajeev , Molineros Jose
Published: December 2015

Augmented reality (AR) has the goal of enhancing a person's perception of the surrounding world, unlike virtual reality (VR) that aims at replacing the perception of the world with an artificial one. An important issue in AR is making the virtual world sensitive to the current state of the surrounding real world as the user interacts with it. For providing the appropriate augmentation stimulus at the right position and time, the system needs some sensor to interpret the surrounding scene. Computer vision holds great potential in providing the necessary interpretation of the scene. While a computer vision-based general interpretation of a scene is extremely difficult, the constraints from the assembly domain and specific marker-based coding scheme are used to develop an efficient and practical solution. We consider the problem of scene augmentation in the context of a human engaged in assembling a mechanical object from its components. Concepts from robot assembly planning are used to develop a systematic framework for presenting augmentation stimuli for this assembly domain. An experimental prototype system, VEGAS (Visual Enhancement for Guiding Assembly Sequences), is described, that implements some of the AR concepts for guiding assembly using computer vision.
The Zircus Concept Sketch for a Learning Environment and Online Community
Authors: Strohecker Carol
Published: December 2015

This paper describes premises of a video, Zircus, presenting a design for a virtual environment. The video is a basis for discussion—a sketch, rather than a specification, of a virtual playspace and interactions that can happen there. The playspace is conceived as a learning environment in which constructive activities can focus thinking on certain sets of ideas. Conversations within the multiuser environment can also be conducive to learning, as well as to developing an online community. These actions and conversations would depend on a future system combining technologies in networked graphics, speech, AI, various input devices, and high-level software for constructing animations and audio/video sequences. Taking the ideas in Zircus from sketch to implementation will require contributions from researchers in a range of disciplines, including architectural design, film media, learning theory, and computer science.
Confluence of Computer Vision and Interactive Graphies for Augmented Reality
Authors: Klinker Gudrun J. , Ahlers Klaus H. , Breen David E. , Chevalier Pierre-Yves , Crampton Chris , Greer Douglas S. , Koller Dieter , Kramer Andre , Rose Eric , Tuceryan Mihran , Whitaker Ross T.
Published: December 2015

Augmented reality (AR) is a technology in which a user's view of the real world is enhanced or augmented with additional information generated from a computer model. Using AR technology, users can interact with a combination of real and virtual objects in a natural way. This paradigm constitutes the core of a very promising new technology for many applications. However, before it can be applied successfully, AR has to fulfill very strong requirements including precise calibration, registration and tracking of sensors and objects in the scene, as well as a detailed overall understanding of the scene. We see computer-vision and image-processing technology playing an increasing role in acquiring appropriate sensor and scene models. To balance robustness with automation, we integrate automatic image analysis with both interactive user assistance and input from magnetic trackers and CAD models. Also, in order to meet the requirements of the emerging global information society, future human-computer interaction will be highly collaborative and distributed. We thus conduct research pertaining to distributed and collaborative use of AR technology. We have demonstrated our work in several prototype applications, such as collaborative interior design and collaborative mechanical repair. This paper describes our approach to AR with examples from applications, as well as describing the underlying technology.
Judgments of the Distance to Nearby Virtual Objects: Interaction of Viewing Conditions and Accommodative Demand
Authors: Ellis Stephen R. , Menges Brian M.
Published: December 2015

Ten subjects adjusted a real-object probe to match the distance of nearby virtual objects optically presented via a see-through, helmet-mounted display. Monocular, biocular, and stereoscopic viewing conditions were used with two levels of required focus. Observed errors may be related to changes in the subjects' binocular convergence. The results suggest ways in which virtual objects may be presented with improved spatial fidelity.
Some Perspectives on Performed Sound and Music in Virtual Environments
Authors: Pressing Jeff
Published: December 2015

The great variety of functions possible for sound in virtual environments is surveyed in relation to the traditions that primarily inform them. These traditions are examined, classifying sound into the three categories of artistic expression, information transfer, and environmental sound. The potentials of and relations between sonification, algorithmic composition, musicogenic and sonigenic displays, virtual musical instruments and virtual sound sources are examined, as well as the practical technical limitations that govern performance control of MIDI and real-time DSP sound synthesis in coordination with visual display. The importance of music-theoretic and psychological research is emphasized. The issues and developed categorizations are then applied to a case study: the examination of a specific virtual environment performance by a team of workers in Australia in which the author worked as composer/performer/ programmer.