Abstract: An experimental study of interaction in a collaborative desktop virtual environment is described. The aim of the experiment was to investigate if added haptic force feedback in such an environment affects perceived virtual presence, perceived social presence, perceived task performance, and task performance. A between-group design was employed, where seven pairs of subjects used an interface with graphic representation of the environment, audio connection, and haptic force feedback. Seven other pairs of subjects used an interface without haptic force feedback, but with identical features otherwise. The PHANToM, a one-point haptic device, was used for the haptic force feedback, and a program especially developed for the purpose provided the virtual environment. The program enables for two individuals placed in different locations to simultaneously feel and manipulate dynamic objects in a shared desktop virtual environment. Results show that haptic force feedback significantly improves task performance, perceived task performance, and pereceived virtual presence in the collaborative distributed environment. The results suggest that haptic force feedback increases perceived social presence, but the difference is not significant.

Abstract: This paper explores and evaluates the support for object-focused interaction provided by a desktop Collaborative Virtual Environment. An experimental “design” task was conducted, and video recordings of the participants' activities facilitated an observational analysis of interaction in, and through, the virtual world. Observations include: problems due to “fragmented” views of embodiments in relation to shared objects; participants compensating with spoken accounts of their actions; and difficulties in understanding others' perspectives. Implications and proposals for the design of CVEs drawn from these observations are: the use of semidistorted views to support peripheral awareness; more explicit or exaggerated representations of actions than are provided by pseudohumanoid avatars; and navigation techniques that are sensitive to the actions of others. The paper also presents some examples of the ways in which these proposals might be realized.

Abstract: We look at differences between the experience of virtual environments and physical reality, and consider making the technical limitations which cause these differences 'visible', aiming to provide resources to enhance communication between users. Three causes of such discrepancies are considered to illustrate this idea: field-of-view; haptic feedback; and network delays. For each, we examine ways of revealing the limitations of the virtual world as resources to better understand the intricacies of system and co-user behaviour. These examples introduce a broader discussion of design issues involved in producing interfaces for day-to-day collaboration through virtual environments. Issues include: the application and activity undertaken through the virtual world; the ability to focus on the business at hand rather than the system in use; and extent of users' familiarity with application and system.

Abstract: This paper explores the concept of multiple perspectives to enhance collaboration by allowing remote participants to tailor their views, user-interfaces and roles to their particular needs and expertise. It describes a preliminary design study conducted on users of a collaborative CAVE-based virtual reality tool for visualizing occanographic data. Results will focus on the patterns of activity within this environment, in particular the manner in which participants transition between individual and group work during the course of a collaborative session.

Abstract: Permission to make digital or hard copies of all or part of this work for personal or classroom use is granted without fee provided that copies are not made or distributed for profit or commercial advantage and that copies bear this notice and the full citation on the first page. To copy otherwise, to republish, to post on servers or to redistribute to lists, requires prior specific permission and/or a fee. CVE 2000 San Francisco CA USA Copyright ACM 2000 1-58113-303-0/00/09...$5.00 ABSTRACT Existing immersed virtual reality and particularly augmented reality systems are usually based on dedicated and expensive hardware and I/O devices. Nevertheless they often provide limited support for the collaboration between multiple users and can hardly be used for arbitrary location independent application environments. Additionally, navigation and interaction within such virtual environments are not very natural or intuitive, making them difficult to use. This paper will introduce a new collaborative augmented reality environment the Virtual Round Table. This environment is designed to support location-independent mixed reality applications, overcoming the limitations for collaboration and interaction of existing approaches. Moreover it extends the physical workplace of the users into the virtual environment, while preserving traditional verbal and non-verbal communication and cooperation mechanisms.

Abstract: In this study we compared collaboration on a puzzle-solving task carried out by two persons in a virtual and a real environment. The task, putting together a cube consisting of different coloured blocks in a 'Rubiks' cubetype puzzle, was performed both in a shared virtual environment (VE) setting, using a Cave-type virtual reality (VR) system networked with a desktop VR system, and with cardboard coloured blocks in an equivalent real setting. The aims of the study were to investigate collaboration, leadership and performance in the two settings. We found that the participants contributed unequally to the task in the VE, and also differences in collaboration between the virtual and the real setting.

Abstract: In large distributed corporations, distributed design review offers the potential for cost savings, reduced time to market, and improved efficiency. It also has the potential to improve the design process by enabling wider expertise to be incorporated in design reviews. This paper describes the integration of several components to enable distributed virtual design review in mixed multi-party, heterogeneous multi-site 2D and immersive 3D environments. The system provides higher layers of support for collaboration including avatars, high fidelity audio, and shared artifact manipulation. The system functions across several interface environments ranging from CAVEs to Walls to desktop workstations. At the center of the software architecture is the Human Integrating Virtual Environment (HIVE) [6], a collaboration infrastructure and toolset to support research and development of multi-user, geographically distributed, 2D and 3D shared applications. The HIVE functions with VisualEyes software for visualizing 3D data in virtual environments. We also describe in detail the configuration and lessons learned in a two site, heterogeneous multi-user demonstration of the system between HRL Laboratories in Malibu, California and GM R&D in Warren, Michigan.

Abstract: A SpaceTag is a virtual object that can be accessed only from limited locations and time period. Users of the SpaceTag System can see and create SpaceTags using a portable terminal with a location sensor. We have categorized it as an overlaid virtual system, in which virtual objects are overlaid onto the real world based on time and space coordinates. This architecture is more promising, general purpose, low-cost, and more realistic than other location-aware system architectures like augmented reality that attaches virtual information onto real objects. The SpaceTag System can be offered as a public information service that is a common platform for gaming, advertising, city guide information, etc. We have already implemented a prototype. In this paper, active SpaceTags are additionally proposed. They are enabled to interact autonomously with human and other SpaceTags, realizing new applications of interactive games, virtual creatures (SpacePet), etc. The computation model of active SpaceTag is described here. This paper also gives a discussion by regarding the SpaceTag System as a CVE. It is a considered as special CVE that has a same space/time coordinates as the real world. SpaceTags and SpacePets can be regarded as objects and active objects in the virtual space, but they are projected onto the real world. Users can communicate with each other through these objects. This paper also describes how such communication occurs.

Abstract: Inhabited television combines collaborative virtual environments (CVEs) with broadcast television so that on-line audiences can participate in television shows within shared virtual worlds. We describe a series of experiments with inhabited television, beginning with the NOWninety6 poetry performance, The Mirror, and Heaven & Hell—Live. These early experiments raised fundamental questions for inhabited television concerning the extent to which it is possible to establish fast-paced social interaction within a CVE, and to which it is possible to produce a coherent and engaging broadcast of this action. We then present a fourth more recent experiment, Out of This World, that directly addressed these questions. We describe how the formulation of inhabited television design principles, combined with the use of dedicated production software for scripting and directing a show and for controlling virtual cameras, enabled us to create a fast-moving and more coherent experience.

Abstract: Virtual Environments (VE) present a complex problem with interesting non-trivial challenges for system development, in particular when the VE is distributed and shared amongst multiple participants. Most problems are common to any VE system, however the development effort is replicated because current systems are neither evolutionary nor allow integration of code across different systems.This paper presents the Java Adaptive Dynamic Environment (JADE), which consists of a light-weight cross-platform kernel with inherent capabilities for dynamic extensibility in run-time. This kernel is the embodiment of a component framework for the underlying infrastructure of VE systems, addressing the problems of evolution and integration.

Abstract: This paper describes a collaborative virtual environment, Teatrix, developed with the aim of bringing drama activities into a virtual stage Drama activities and story telling play important roles in children development Based on this premise and also on real classroom activities, we developed Teatrix as a collaborative virtual environment, where both drama and story creation are merged into a unique medium providing a form of collaborative make-believe for children In this paper we will focus on the design, architecture and preliminary results of Teatrix, as well as on the future steps of the research

Abstract: The Forum is a collaborative working environment that consists of two shared spaces: a space for informal interaction (Contact Space), and a workspace for synchronous meetings using audioconferencing support (Meeting Space). It is designed to enable people, who should meet each other to do so naturally, providing an environment for richer online interactions. This paper discusses three evaluations of the Forum Contact Space: a conceptual evaluation, a prototype evaluation, and an ethnographic evaluation. Each evaluation was undertaken to improve the Contact Space usability, examine whether it supports chance encounters, and learn from participant feedback, areas for improvement of future Forum versions.The conceptual evaluation using focus groups showed group discrepancies regarding how the Contact Space would be beneficial for producing chance encounters. In the prototype evaluation, the findings suggest that chance encounters were produced and that the Concept Space was perceived as an environment for supporting group cohesiveness. A common theme from the findings of the ethnographic evaluation was the division of the Contact Space and its related parts into two tools: a core tool; and a peripheral tool, dependent on whether it was active. As groups are increasingly distributed over geographical distances, the benefits of a shared virtual space for communication and interaction are being realised.

Abstract: In this work, we present a new method for displaying stereo scenes, which speeds up the rendering time of complex geometry. We first discuss a scene splitting strategy, allowing us to partition objects to the distant background or the near foreground. Furthermore, wededuce a computation rule for positioning a cutting plane in the scene.

Abstract: Author(s): Staadt, Oliver G.; Kunz, A.; Meier, M.; Gross, Markus | Abstract: In this paper, we report ongoing work in a new project, The Blue-C. The goal of this project is to build a collaborative, immersive virtual environment which will eventually integrate real humans, captured by a set of video cameras. Two Blue-C.s will be interconnected via a high-speed network. This will allow for bi-directional collaboration and interaction between two persons sharing virtual spaces. The video streams are used for both texture and geometry extraction. We will generate a 3-D light field inlay enriched with the reconstructed geometry, which will be integrated into the virtual environment. The design and construction of the Blue-C. environment, including both hardware and software, is an interdisciplinary effort with participants from the departments of computer science, architecture, product development, and electrical engineering. Parallel to the development of the core system, we are designing new applications in the areas of computer aided architectural design, product reviewing, and medicine, which will highlight the versatility of the Blue-C.

Abstract: In this paper we describe and analyse the community building process for Ages of Avatar, a set of on-line Collaborative Virtual Environments created in MicrosoftVirtual Worlds, which form part of an ongoing experiment in Inhabited Television, aiming to merge CVEs and broadcast media. We describe the means by which the CVEs were launched, promoted and supported alongside a television broadcast channel, and how actions of viewers acting as inhabitants in the CVE can be used to provide broadcast material. We explain how the world content and their super-structure were managed to encourage the growth of a community over a short period of time. Using logs of activities in the worlds we deduce some of the characteristics of the community which was formed.

Abstract: This talk examines some models of 'space' and things in space drawing from diverse areas: mathematics (my first love), architecture, cognition as well as those developed specifically for VR; and shows how these impact and inform virtual space. Also important is the human geography of virtual space and the Internet which has been particularly important to me recently with my company hat on – mapping the interrelationships between communities of users and service providers in the Internet (we call it market ecology). This is in turn related to recommender systems, virtual communities and e-commerce. Models of 'space' from physics are not the same as those from our day-to-day experience, and neither has stayed constant through time. cyberspace challenges these models more fundamentally still, not just virtual reality, but all forms of mixed reality, mobile and ubiquitous computing. By understanding some of these models of space we may be able to better understand and better design the space of tomorrow.

Abstract: The interaction models found in typical desktop virtual environments designed for social interactions need to be improved in order to provide an adequate sense of embodiment and appropriate levels of abstraction for collaborative tasks. In order to improve the kinds of user interfaces available in social desktop virtual environments, new mechanisms for embodied interaction are needed. Such mechanisms would allow the dynamic generation of user interface displaying currently available high-level actions that can be performed on objects. This paper evaluates the kinds of interactions currently available in social desktop virtual environments, explores how these interactions effect the end-user experience, and suggests possible solutions for improving a user's sense of embodiment and presence in such environments.

Abstract: In this paper, we present and compare two examples of the use of the Active Worlds client/server technology for implementation of 3D multi-user virtual science museums: SciCentr, developed as a standalone environment at the Cornell Theory Center, Cornell University's high-performance computing center, and Biolearn, a virtual visitors center for the proposed LifeLearn Bioregional Learning Center on the Northern California Coast. SciCenter focuses on interactive exhibits analogous to those of a traditional hands-on science center, but presented solely within the virtual space. In contrast, BioLearn is designed to provide a globally accessible interactive tour of the seaside museum and preserve by offering web-based information about the bioregion in a dynamic, natural 3D setting.

Abstract: Three suggestions are made for extensions from and to CVE's: awareness of others, multiple media, and scalability. Awareness of others and their activities is strongly desirable in all media and applications, not just in CVE's. Multiple media are not seriously catered for in existing CVE's, and a suitable architecture will precede popular applications. CVE's need to be scalable to greater numbers of people, and achieving this also has implications for greater flexibility and reconfigurability. With respect to awareness of others, we argue that the Web and most document handling applications are unaware of others in the workgroup or community, and this limits the ability to support real work practice. We present a Web application (CRACK!) that provides 'people-awareness' in the Web, between the Web and VR's, and that should be extensible to other standard document handling programs. With respect to multiple media, we argue that many media are needed for collaboration, since each has its own special benefits and affordances. We present a scalable architecture for handling multiple media (VR, video, audio, text, and documents). An important feature of the architecture is that the presentation level integration. With respect to scalability we note that upward scalability is important as it also gives a new ability to join, re-divide, and thus create new 'worlds'. We give an example of a novel dynamic partitioning algorithm to achieve upward scalability. We argue that 'downward' scalability to e.g. mobiles, and 'sideways scalability' to specialist e.g. audio or video devices is important in achieving multiple media CVE's. Taken together, these innovations may stimulate new generations of CVE's.

Abstract: The conference is a long-standing tradition in professional circles, playing a central role in informal and formal knowledge building and social network maintenance. Networked communication technologies have influenced both conference logistics and organization and the intellectual and social experience of conference participants. Conducting a virtual conference raises many issues that are directly relevant to the study of information technologies in organizational settings. Virtual conferences may allow for broader access to social networks, but also impose significant constraints on the communication environment. This paper investigates two conferences conducted in the 3-D virtual environment ActiveWorlds, and one conference conducted primarily in a text-based chat environment. Text and video records are balanced by the personal observations of the author, who participated in an online panels and presentations in each environment. This paper aims to highlight the potential benefits and challenges of collaborative virtual environments in mediating professional conferences.

Abstract: In this paper, we report ongoing work in a new project, The Blue-C. The goal of this project is to build a collaborative, immersive virtual environment which will eventually integrate real humans, captured by a set of video cameras. Two Blue-C.s will be interconnected via a high-speed network. This will allow for bi-directional collaboration and interaction between two persons sharing virtual spaces.The video streams are used for both texture and geometry extraction. We will generate a 3-D light field inlay enriched with the reconstructed geometry, which will be integrated into the virtual environment.The design and construction of the Blue-C. environment, including both hardware and software, is an interdisciplinary effort with participants from the departments of computer science, architecture, product development, and electrical engineering. Parallel to the development of the core system, we are designing new applications in the areas of computer aided architectural design, product reviewing, and medicine, which will highlight the versatility of the Blue-C.

Abstract: provides a coordination mechanism to help to maintain an interaction order among the participants and to make it more efficient. The collaborative virtual environments have become a good alternative to construct collaborative learning systems. In this paper we present DeskTOP, a collaborative virtual environment implemented on the Web to support and to promote collaborative learning in university courses. This environment is designed mainly from the perspective of the desk and room metaphors. It makes use of design patterns in its architecture, promote the creation of customized collaborative learning environments and support a communication, collaboration and social interaction between lecturer and students through a shared virtual space. 2.2 Metaphors used in DeskTOP design The DeskTOP system uses the hall and collaboration rooms metaphors, as metaphors of place [3]; and the desk metaphor, as metaphor of interface [9]. The hall metaphor establishes a virtual environment which promotes public casual and informal interaction among its users. The collaboration rooms metaphor helps to represent shared environments within which the user can work in group. Through this metaphor, a common area is created for private interaction which provides users with working tools. Figure 2.1 represents the idea of these two metaphors.

Abstract: A chatspace was developed that allows conversation with 3D sound using networked streaming in a shared virtual environment. The system provides an interface to advanced audio features, such as a “whisper function” for conveying a confided audio stream. This study explores the use of spatial audio to enhance a user's experience in multiuser virtual environments.

Abstract: Recent advances in both communication systems and collaboration technologies have resulted in a convergence of communication and interactive systems supporting different forms of collaboration across a community of users. Work on technology-mediated collaboration has traditionally taken one of two broad approaches. The first is to focus on the work activity itself, and to find ways to distribute and coordinate that activity across different individuals, perhaps working at different times and in different locations. This approach is embodied in many of the groupware products currently emerging in the marketplace. The second is to focus on the environment within which work takes place, whether that environment is the physical setting or the computational workspace, and find ways to allow people to come together in that environment to achieve collaborative work. This approach has tended to exploit the nature and organization of space as a means of managing work. The application of spatial concepts has considered both augmenting existing physical spaces with electronically sensitive physical artefacts, and virtual spaces into which users project their presence. Our particular interest in this special issue is on Collaborative Virtual Environments that allow users to share an artificial space. Collaborative Virtual Environments, or CVEs, are perhaps the most radical form of spatially oriented cooperative systems. Emerging from research into realtime graphics, virtual reality, and computationally shared workspaces, CVEs are virtual environments which can be simultaneously occupied by distributed individuals, who come together to achieve some collective activity much as, in the everyday world, we gather to work in meeting rooms, in offices, in hallways, or around the coffee machine. The early days of research into CVEs were dominated by the technological resources needed to implement them, including head-mounted displays and dedicated rendering engines with high-performance graphics pipelines. However, Moore’s Law has had its inexorable effect on CVE research as much as on any other area of technological exploration, with the result that the resources needed to support collaborative virtual environments are now incorporated into standard PCs. For example, fairly standard PC graphics cards are currently delivering graphical rendering performances that were almost exclusively the preserve of high-end graphics workstations. With the technical barriers lowered, and with the ever-widening deployment of relatively high-speed network connections, CVEs have become much more accessible in support of everyday collaboration. We have seen a range of on-line internet environments emerge, and communities have developed that make use of these environments. Many of these on-line environments

Abstract: In this poster paper, we introduce the DISCOVER project, which is developing a CVE for teams to practice managing emergencies in offshore and maritime domains. Many factors constrain design in such contexts. Here we describe just one of them, the need for a particularly convincing sense of reality, and hence the lack of scope for 'magical' devices to support navigation and awareness. We outline the research and design challenges which this entails.

Abstract: asp (General Animation and Simulation Platform) was at rst designed to distribute the animation and simulation of multi-agent virtual environments. In the Gasp framework, a virtual world is composed of any number of simulation ob- jects. These simulation objects can be autonomous agents, interactors or user representations. We dene interactors as simulation objects which provide information on user input readable by any simulation object. Because simulation ob- jects can read information from any number of other simula- tion objects, it is then quite easy to design objects on which any number of users (or other simulation objects) can col- laborate. As the Gasp run-time kernel can distribute the calculations associated with those simulation objects on dif- ferent workstations, collaborative virtual environments can easily be built. In this paper, we explain how, in our frame- work, interactors and interactive objects are distributed for collaborative interactions and how it is possible to build an interactive object from an existing object without changing the code of that object.

Abstract: This paper introduces a Distributed Virtual Realit yplatform based on oRis, our dynamic and interpreted multi-agent language. This platform, called AReViDis, has been designed for collaborative interactiv e protot yping.During an AReViDis session, the dynamic properties of oRis allow the addition, modification or destruction of virtual agen ts in a distributed virtual environment.These modifications may either be introduced by the agents themselves or b y the users through various Computer Human Interfaces (CHI). These modifications may also be received accross the netw ork allowing communications in shared virtual worlds.

Abstract: 1. THE IDEA The basic idea behind the sTeam project (structuring information in a team) is to provide students and teachers with technical means to create their own personal memories, archives and libraries by referring to a largely incoherent environment of distributed knowledge. The sTeam approach embodies a strict learner centred perspective. To accomplish this, we have developed a client-server system that combines two traditionally separated architectures, document management systems (DMS) and collaborative virtual environments (CVEs). Since future developments should be based on learners` experiences, an open source approach has been taken.

Abstract: In this work, we present a new method for displaying stereo scenes, which speeds up the rendering time of complex geometry. We first discuss a scene splitting strategy, allowing us to partition objects to the distant background or the near foreground. Furthermore, wededuce a computation rule for positioning a cutting plane in the scene.