When a two-dimensional (2D) traveling salesman problem (TSP) is presented on a com- puter screen, human subjects can produce near-optimal tours in linear time. In this study we tested human performance on a real and virtual floor, as well as in a three- dimensional (3D) virtual space. Human performance on the real floor is as good as that on a computer screen. Performance on a virtual floor is very similar, while that in a 3D space is slightly but systematically worse. We modeled these results by a graph pyramid algorithm. The same algorithm can account for the results with 2D and 3D problems, which suggests that deterioration of performance in the 3D space can be attributed to geometrical relations between hierarchical clustering in a 3D space and coarse-to-fine production of a tour.

Full scale physical mock-ups of specific hospital units such as patient rooms are routinely utilized to serve the multiple purposes of constructors, designers, and owner stakeholders for healthcare facility projects. The shortcoming with this practice is that the mock-up is constructed during the construction phase and is of limited use for making extensive decisions regarding the functionality of the room design. Three-dimensional visualisation tools offer healthcare facility stakeholders the opportunity to comprehend proposed designs more clearly during the planning and design phases, thus enabling the greatest influence on design decision making. While several options exist, based on their experience with a bariatric patient room model, the authors promote the utilization of Virtual Reality mock-ups for design review because of their enhanced capacity for an immersive, interactive experience with the design and for the long-term utility of such models for the balance of the project life cycle.

In the wake of building information modelling, virtual reality is receiving attention for visualizing design details by means of virtual prototypes or virtual mock-ups. Examples for courthouse design review have prompted application to healthcare facilities. To facilitate perspective for patient-centred and evidence-based design, highly interactive, immersive virtual modelling is promoted to assist project stakeholders in validating design alternatives. This approach requires a significant database of model components to achieve timely turnaround of model concepts. The modelling of interactive elements (e. g. opening doors, folding beds) consumes more time than acceptable to the typical healthcare facility project team. The authors therefore are establishing a technology HUB to act as a central repository for object models shared by contributing partners. The HUB is intended to advance this approach and speed arrival to final product. The plan for this collaborative vehicle is described, as are issues relevant to partnering in this manner.

This paper presents three psychophysical experiments that attempt to determine whether human perception of force amplitude is isotropic in a virtual environment (VE). Participants employed passive or active forces in the same or different directions. Our results indicate that, regardless of whether stimulus presentation and response are active or passive, human perception of force amplitude is in fact anisotropic. Implications of these results for design of VR systems are briefly discussed.

The dilemma of VR as medium for new media art has been that of its immaterial nature and an almost conscious denial of the material world, including interactors' bodies. This paper introduces a conceptual infrastructure, examples of artistic explorations and a concrete technological system for a strong integration of 3D computer graphics and physical space. It explains the three interrelated parts of our infrastructure: image, interface and physical space related to art and design practice. Relevant concepts of navigation, site specific simulation and reality jamming are illustrated in our actual artistic explorations and the paper closes with ideas for future project work based on a novel technological system interfacing the Arduino I/O board to VRJuggler and OpenGL, which can be of benefit to research and experimentation in both, the arts and technology.

"Life beyond the browser: The TeraDRE," Proceedings of the Grid Computing Environments (GCE) workshop. Held at the Reno Convention Center: Reno, Nevada: 11-12 November 2007.

The general goal of our research is the creation of a natural and intuitive interface for navigation, interaction, and input/recognition of American Sign Language (ASL) math signs in immersive Virtual Environments (VE) for the Deaf. The specific objective of this work is the development of two new gesture recognition systems for SMILE™, an immersive learning game that employs a fantasy 3D virtual environment to engage deaf children in math-based educational tasks. Presently, SMILE includes standard VR interaction devices such as a 6DOF wand, a pair of pinch gloves, and a dance platform. In this paper we show a significant improvement of the application by proposing two new gesture control mechanisms: system (1) is based entirely on hand gestures and makes use of a pair of 18-sensor data gloves, system (2) is based on hand and body gestures and makes use of a pair of data gloves and a motion tracking system. Both interfaces support first-person motion control, object selection and manipulation, and real-time input/recognition of ASL numbers zero to twenty. Although the systems described in the paper rely on high-end, expensive hardware, they can be considered a first step toward the realization of an effective immersive sign language interface.

This paper discusses the development of a multi grid-domain application for users of the Purdue TeraDRE resource. The TeraDRE (Distributed Rendering Environment on the TeraGrid) allows a user to greatly reduce the render time of their 3D animations using a cluster of distributed computers, while providing temporary storage for large animations. It has been used successfully by Purdue researchers and students in a number of projects where animations were generated, and is now a service available on the TeraGrid. As we broaden the access to this distributed rendering service, we foresee several challenges. One of the key challenges is to support users coming from different grid domains that require different authentication methods. We also face the increasing demand for the support of multiple rendering engines. To meet these and other demands, we have developed the next generation grid-aware TeraDRE as a gateway for users from TeraGrid, Open Science Grid and other organizations. Using the Java Web Start technology, the new generation TeraDRE provides a user friendly interface that supports the end-to-end workflow needed to render 3D graphics and animations on the grid. The grid-aware TeraDRE is rich with features such as automatic video file production, previews and notification on web-capable mobile devices. It also supports multiple rendering engines, including the open source renderers POV-Ray and Blender.

Visible Past proposes a cross platform, scalable environment (Exploratorium) for collaborative social, geographic, and historical education and research. The Exploratorium will be deployed in a variety of settings, from Web to fully immersive virtual reality environments. Educational activities can be formal (classroom teaching) or informal (conducted in a museum or self–directed online learning setting). The specific goals of the Exploratorium concept are two–fold: 1) to create a set of tools for collecting, organizing, or disseminating knowledge in a collaborative manner at various scales and in various formats; and, 2) to extend and refine a theoretical framework and methodological tools for prototyping and testing future research and learning applications and architectures that benefit from 3D and location aware applications. The heart of the Visible Past Exploratorium concept, the Exploratorium, is an information space built on top of a georeferenced wiki database that can be accessed through a variety of avenues: full immersion 3D environments, Web interfaces, or Geographic Exploration Systems (GES), such as Google Earth or NASA’s World Wind.

In this paper we describe the development of a new immersive 3D learning environment to increase mathematical skills of deaf children. The application teaches mathematical concepts and ASL (American Sign Language) math terminology through user interaction with fantasy 3D virtual signers and environments. The program can be displayed in immersive devices and includes a gesture control system comprised of a pair of pinch gloves and a 6-degrees-of-freedom wrist tracker.

With the high powered rendering systems and recording equipment available today, 4k video streams are now within the reach of several scientific communities. A resolution of 4096x3072, with 24-bit color, running at 30 frames per second, produces just under 10Gbs of network traffic. Existing tiled displays are being used to show such media, and these high resolution streams are being sent across the country. Because of the data throughput required for 4k video streams, pulling stored video off storage systems in real time is not possible. So current systems providing 4k video streams either use a live source, such as a high-definition camera, or use lossy compression to store the video and transmit it using 1Gb networks. We propose the construction of a system to stream stored media (either recorded video or rendered graphics) at full non-compressed resolution to tiled displays.

In this paper we describe the development of a new immersive 3D learning environment to increase mathematical skills of deaf children. The application teaches mathematical concepts and ASL (American Sign Language) math terminology through user interaction with fantasy 3D virtual signers and environments. The program can be displayed in immersive devices and includes a gesture control system comprised of a pair of pinch gloves and a 6-degrees-of-freedom wrist tracker. Our application improves on existing examples of virtual learning environments for the hearing impaired in terms of: (1) high realism/fluidity of the 3D characters' signing motion; (2) complexity of real time interaction between student and 3D avatars and environments; and (3) natural communication between user and application via a simple glove-based gesture control system.

This paper describes an immersive interactive virtual environment created to educate students about ecosystem dynamics. Traditional tools and methods for teaching theories regarding these dynamics use 2D static images that cannot adequately display to students the complex nature of the interactions taking place in the ecosystem, making it difficult to understand the underlying theory. An immersive interactive environment can help overcome these difficulties by allowing students to view a 3D simulation and interact with it in real-time to understand the effects of changes to the ecosystem.

The anthrax attacks of 2001 brought professional and public attention to the significance of successful crisis communication in the context of bioterrorism. The project discussed in this paper is an initiative taken to respond to the calls for more effective bio-terror crises communication training. The goal of this project is to address various challenges in bio-terror crises communication by developing an innovative crisis communication training module for public relations students. This goal is achieved by attending to two main factors: (a) keen awareness of important theories in crises communication response, and (b) "hands-on" training in real-time bio-terror communication handling techniques. This paper introduces the process taken to develop 3D simulated crisis communication training material and presents future plans to assess its effectiveness.

The Access Grid (AG) [1] enables group-to-group collaborations through the integration of resources such as multiple camera views, large-format displays, shared audio, and interfaces to visualization environments. It is a powerful tool that allows for face to face communication among all the sites participating in a venue (virtual room where meetings take place.) Purdue University, Iowa State University, and Indiana University have been collaborating for the last few years on jointly delivering specialized graduate courses in virtual reality and interactive technologies over the AG. This paper presents our experiences on integrating the AG into the graduate curriculum at

With the high powered rendering systems and recording equipment available today, 4k video streams are now within the reach of several scientific communities. A resolution of 4096x3072, with 24-bit color, running at 30 frames per second, produces just under 10Gbs of network traffic. Existing tiled displays are being used to show such media, and these high resolution streams are being sent across the country. Because of the data throughput required for 4k video streams, pulling stored video off storage systems in real time is not possible. So current systems providing 4k video streams either use a live source, such as a high-definition camera, or use lossy compression to store the video and transmit it using 1Gb networks. We propose the construction of a system to stream stored media (either recorded video or rendered graphics) at full non-compressed resolution to tiled displays.

We present a novel approach for a virtual granular material interactive manipulation with force feedback. A user can interactively change a height-field model of sand by dragging objects inside. The virtual sand behaves like real sand moving to the sides and falling back, filling holes and irregularities on the surface. The dragging object position is controlled by a haptic device that provides a position in 3D space that correspondingly changes the sand model. The sand model provides force feedback to the haptic device resulting in two principal forces; the repulse that has vertical direction and the viscous drag. The resulting force is delivered back to the haptic device. The user can sense the sand’s response as the dragging object moves through the virtual sand. This results in the haptic-visual feedback providing a higher degree of plausibility than visual feedback alone.

The work presented in this poster is a study of cybersickness in 450 visitors to a virtual reality (VR) lab on a university campus. Researchers observed several interesting trends, including an increased incidence and severity of sickness among older visitors and lower incidence and severity of sickness in younger visitors. This finding is in direct contrast to studies of traditional motion sickness commonly sited in the VR literature, and was first presented in our previous poster [Arns & Cerney 2005]. Other factors, including gender, level of game play, presence score and susceptibility rating were examined as secondary factors. The current poster covers some other interesting findings of the study.

This paper discusses the implementation of a distributed rendering environment (DRE) utilizing the TeraGrid. Using the new system, researchers and students across the TeraGrid have access to available resources for distributed rendering. Previously, researchers at universities and national labs, using high end rendering software such as Renderman Compliant Pixie were often limited by the amount of time that it takes to calculate (render) their final images. The amount of time required to render introduces several potential complications in a research setting. In contrast, a typical animation studio has a render farm, consisting of a cluster of computers (nodes) used to render 3D images, known as a distributed rendering environment. By spreading the rendering across hundreds of machines, the overall render time is reduced significantly. Unfortunately, most researchers do not have access to a distributed rendering environment. Our university has been developing a DRE for local use. However, because we are a TeraGrid site, we recently modified our DRE implementation to make use of open source rendering tools and grid tools such as Condor, in order to make the DRE available to other TeraGrid users

Immersive stereoscopic display systems built from commodity PCs and equipment are becoming increasingly common. Although such systems are generally used for interactive experiences, it is occasionally useful to instead display stereoscopic movies. This paper discusses a method of creating pre-rendered stereoscopic movies for display with an inexpensive, commodity-based, passive stereoscopic display wall. Playback methods, possible uses, and experiences with early movies are also discussed. We first describe our display system, which uses the spanned desktop mode of video cards with dual video outputs, and a pair of projectors with polarizing filters. We then explain our method for creating stereo pair movies (left/right or top/bottom) using video compositing software. While the concept is straightforward, one difficulty that must be addressed is using an appropriate video codec that can be displayed in full screen, across two displays, at the desired resolution, file size, playback rate, and visual quality. A number of tests were performed to find video codecs that would be suitable for stereo movies based on these attributes. Results are provided in a comparison of multiple codecs that can aid in the successful implementation of this method. Several codecs are recommended, but specific codecs should be chosen based on individual needs.