Holger Regenbrecht

The Experience of Presence: Factor Analytic Insights

Within an embodied cognition framework, it is argued that presence in a virtual environment (VE) develops from the construction of a spatial-functional mental model of the VE. Two cognitive processes lead to this model: the representation of bodily actions as possible actions in the VE, and the suppression of incompatible sensory input. It is hypothesized that the conscious sense of presence reflects these two components as spatial presence and involvement. This prediction was confirmed in two studies (N = 246 and N = 296) assessing self-reports of presence and immersion experiences. Additionally, judgments of realness were observed as a third presence component. A second-order factor analysis showed a distinction between presence, immersion, and interaction factors. Building on these results, a thirteen-item presence scale consisting of three independent components was developed and verified using confirmatory factor analyses across the two studies.

Augmented reality projects in the automotive and aerospace industries

The 2003 International Symposium on Mixed and Augmented Reality was accompanied by a workshop on potential industrial applications. The organizers wisely called it potential because the real use of augmented reality (AR) in an industrial context is still in its infancy. Our own experience in this field clearly supports this viewpoint. We have been actively involved in the research, development, and deployment of AR systems in the automotive, aviation, and astronautics industries for more than five years and have developed and implemented AR systems in a wide variety of environments while working at DaimlerChrysler in Germany. In this article we have selected 10 AR projects from those we have managed and implemented in the past to examine the main challenges we faced and to share some of the lessons we learned.

Measuring the Sense of Presence and its Relations to Fear of Heights in Virtual Environments

This article describes a study in which a genuine effect of presence--the development of fear of virtual stimuli--was provoked. Using a self-report questionnaire, the sense of presence within this situation was measured. It was shown that fear increased with higher presence. The method, which involved 37 participants, was tested and validated with user tests at the Bauhaus University. A growing body of research in human-computer interface design for virtual environments (VE) concentrates on the problem of how to involve the user in the VE. This effect, usually called immersion or the sense of presence, has been the subject of much research activity. This research focuses on the influence of technical and technological parameters on the sense of presence. However, little work has been done on the effects of experienced sense of presence. One field in which a sense of presence is necessary for the successful application of VEs is the treatment of acrophobic patients. Our goals are to (a) create a theory-bas...

Developing a generic augmented-reality interface

We seek to design an AR interface that provides users with interactivity so rich it would merge the physical space in which we live and work with the virtual space in which we store and interact with digital information. In this single augmented space, computer-generated entities would become first-class citizens of the physical environment. We would use these entities just as we use physical objects, selecting and manipulating them with our hands instead of with a special-purpose device such as a mouse or joystick. Interaction would then be intuitive and seamless because we would use the same tools to work with digital and real objects. Tiles is an AR interface that moves one step closer to this vision. It allows effective spatial composition, layout, and arrangement of digital objects in the physical environment. The system facilitates seamless two-handed, three-dimensional interaction with both virtual and physical objects, without requiring any special-purpose input devices.

Real and illusory interactions enhance presence in virtual environments

It has long been argued that the possibility to interact in and with a virtual environment (VE) enhances the sense of presence. On the basis of a three-component model of presence, we specify this hypothesis and argue that the mental representation of possible actions should especially enhance spatial presence, and to a lesser extent the involvement and realness of a VE. We support this hypothesis in three studies. A correlative study showed that self-reported interaction possibilities correlated significantly with spatial presence, but not with the other two factors. A first experimental study showed that possible self-movement significantly increased spatial presence and realness. A second experimental study showed that even the illusion of interaction, with no actual interaction taking place, significantly increased spatial presence.

MagicMeeting: A Collaborative Tangible Augmented Reality System

We describe an augmented reality (AR) system that allows multiple participants to interact with 2D and 3D data using tangible user interfaces. The system features face-to-face communication, collaborative viewing and manipulation of 3D models, and seamless access to 2D desktop applications within the shared 3D space. All virtual content, including 3D models and 2D desktop windows, is attached to tracked physical objects in order to leverage the efficiencies of natural two-handed manipulation. The presence of 2D desktop space within 3D facilitates data exchange between the two realms, enables control of 3D information by 2D applications, and generally increases productivity by providing access to familiar tools. We present a general concept for a collaborative tangible AR system, including a comprehensive set of interaction techniques, a distributed hardware setup, and a component-based software architecture that can be flexibly configured using XML. We show the validity of our concept with an implementation of an application scenario from the automotive industry.

Interaction in a collaborative augmented reality environment

In this paper we describe an Augmented Reality (AR) system which allows multiple participants to interact with two- and three-dimensional data using tangible user interfaces. Interactively controllable 2D and 3D information is seamless integrated into the system.

Using augmented virtuality for remote collaboration

This paper describes the concept, prototypical implementation, and usability evaluation of the Augmented Virtuality (AV)-based videoconferencing (VC) system cAR/PE!. We present a solution that allows three participants at different locations to communicate over a network in an environment simulating a traditional face-to-face meeting. Integrated into the AV environment are live video streams of the participants spatially arranged around a virtual table, a large virtual presentation screen for 2D display and application sharing, and 3D geometry (models) within the room and on top of the table. We describe the general concept and application scenario as well as the actual hardware setup, the implementation, and the use of the system in its current state. Results of two usability studies with 87 subjects are presented that show the general usability of our approach as well as good overall satisfaction. Parts of the work described here were presented as a poster at the second International Symposium on Mixed and Augmented Reality (Regenbrecht, Ott, Wagner, Lum, Kohler, et al., 2003. An Augmented Virtuality Approach to 3D Videoconferencing. Poster at 2nd Int. Symp. on Mixed and Aug. Reality, Tokyo.).

Interactive multi-marker calibration for augmented reality applications

Industrial augmented reality (AR) applications require fast, robust, and precise tracking. In environments where conventional high-end tracking systems cannot be applied for certain reasons, marker-based tracking can be used with success as a substitute if care is taken about (1) calibration and (2) run-time tracking fidelity. In out-of-the-laboratory environments multi-marker tracking is needed because the pose estimated from a single marker is not stable enough. The overall pose estimation can be dramatically improved by fusing information from several markers fixed relative to each other compared to a single marker only. To achieve results applicable in an industrial context relative marker poses need to be properly calibrated. We propose a semiautomatic image-based calibration method requiring only minimal interaction within the workflow. Our method can be used off-line, or preferably incrementally online. When used online, our method shows reasonably good accuracy and convergence with workflow interruption of less than one second per incremental step. Thus, it can be interactively used. We illustrate our method with an industrial application scenario.

A tangible AR desktop environment

Abstract We present an AR desktop environment which integrates the standard 2D computer desktop into an augmented 3D space. The underlying physical space is given by the standard office desk used in everyday work. Instead of sitting only in front of a computer screen, the user wears a video-through head mounted displays and interacts with the environment in both tangible and virtual ways. In this augmented environment, standard 2D application windows are attached to physical clipboards and can be freely positioned in the working space by simply moving the clipboard. Additionally, 3D content can be brought into and manipulated within the same space. To support interaction with 3D content we have experimented with a circular platform, on which a 3D model can be placed, and which the user can turn in a natural tangible way. By fusing familiar desktop utensils, two-dimensional computer desktop applications, and three-dimensional models, we provide a seamless transition from the traditional 2D computer desktop to a 3D augmented working environment. The paper describes the concept and implementation of the system and illustrates some interfaces and interaction techniques used in the context of CAD engineering.