On Inter-referential Awareness in Collaborative Augmented Reality

For successful collaboration to occur, a workspace must support inter-referential awareness - or the ability for one participant to refer to a set of artifacts in the environment, and for that reference to be correctly interpreted by others. While referring to objects in our everyday environment is a straight-forward task, the non-tangible nature of digital artifacts presents us with new interaction challenges. Augmented reality (AR) is inextricably linked to the physical world, and it is natural to believe that the re-integration of physical artifacts into the workspace makes referencing tasks easier; however, we find that these environments combine the referencing challenges from several computing disciplines, which compound across scenarios. This dissertation presents our studies of this form of awareness in collaborative AR environments. It stems from our research in developing mixed reality environments for molecular modeling, where we explored spatial and multi-modal referencing techniques. To encapsulate the myriad of factors found in collaborative AR, we present a generic, theoretical framework and apply it to analyze this domain. Because referencing is a very human-centric activity, we present the results of an exploratory study which examines the behaviors of participants and how they generate references to physical and virtual content in co-located and remote scenarios; we found that participants refer to content using physical and virtual techniques, and that shared video is highly effective in disambiguating references in remote environments. By implementing user feedback from this study, a follow-up study explores how the environment can passively support referencing, where we discovered the role that virtual referencing plays during collaboration. A third study was conducted in order to better understand the effectiveness of giving and interpreting references using a virtual pointer; the results suggest the need for participants to be parallel with the arrow vector (strengthening the argument for shared viewpoints), as well as the importance of shadows in non-stereoscopic environments. Our contributions include a framework for analyzing the domain of inter-referential awareness, the development of novel referencing techniques, the presentation and analysis of our findings from multiple user studies, and a set of guidelines to help designers support this form of awareness

Makeup Lamps: Live Augmentation of Human Faces via Projection

We propose the first system for live dynamic augmentation of human faces. Using projector‐based illumination, we alter the appearance of human performers during novel performances. The key challenge of live augmentation is latency — an image is generated according to a specific pose, but is displayed on a different facial configuration by the time it is projected. Therefore, our system aims at reducing latency during every step of the process, from capture, through processing, to projection. Using infrared illumination, an optically and computationally aligned high‐speed camera detects facial orientation as well as expression. The estimated expression blendshapes are mapped onto a lower dimensional space, and the facial motion and non‐rigid deformation are estimated, smoothed and predicted through adaptive Kalman filtering. Finally, the desired appearance is generated interpolating precomputed offset textures according to time, global position, and expression. We have evaluated our system through an optimized CPU and GPU prototype, and demonstrated successful low latency augmentation for different performers and performances with varying facial play and motion speed. In contrast to existing methods, the presented system is the first method which fully supports dynamic facial projection mapping without the requirement of any physical tracking markers and incorporates facial expressions

Projector-Based Augmented Reality for Quality Inspection of Scanned Objects

After scanning or reconstructing the geometry of objects, we need to inspect the result of our work. Are there any parts missing? Is every detail covered in the desired quality? We typically do this by looking at the resulting point clouds or meshes of our objects on-screen. What, if we could see the information directly visualized on the object itself? Augmented reality is the generic term for bringing virtual information into our real environment. In our paper, we show how we can project any 3D information like thematic visualizations or specific monitoring information with reference to our object onto the object’s surface itself, thus augmenting it with additional information. For small objects that could for instance be scanned in a laboratory, we propose a low-cost method involving a projector-camera system to solve this task. The user only needs a calibration board with coded fiducial markers to calibrate the system and to estimate the projector’s pose later on for projecting textures with information onto the object’s surface. Changes within the projected 3D information or of the projector’s pose will be applied in real-time. Our results clearly reveal that such a simple setup will deliver a good quality of the augmented information

Interactive ubiquitous displays based on steerable projection

The ongoing miniaturization of computers and their embedding into the physical environment require new means of visual output. In the area of Ubiquitous Computing, flexible and adaptable display options are needed in order to enable the presentation of visual content in the physical environment. In this dissertation, we introduce the concepts of Display Continuum and Virtual Displays as new means of human-computer interaction. In this context, we present a realization of a Display Continuum based on steerable projection, and we describe a number of different interaction methods for manipulating this Display Continuum and the Virtual Displays placed on it.Mit zunehmender Miniaturisierung der Computer und ihrer Einbettung in der physikalischen Umgebung werden neue Arten der visuellen Ausgabe notwendig. Im Bereich des Ubiquitous Computing (Rechnerallgegenwart) werden flexible und anpassungsfähige Displays benötigt, um eine Anzeige von visuellen Inhalten unmittelbar in der physikalischen Umgebung zu ermöglichen. In dieser Dissertation führen wir das Konzept des Display-Kontinuums und der Virtuellen Displays als Instrument der Mensch-Maschine-Interaktion ein. In diesem Zusammenhang präsentieren wir eine mögliche Display-Kontinuum-Realisierung, die auf der Verwendung steuerbarer Projektion basiert, und wir beschreiben mehrere verschiedene Interaktionsmethoden, mit denen man das Display-Kontinuum und die darauf platzierten Virtuellen Displays steuern kann

Toolkit support for interactive projected displays

Interactive projected displays are an emerging class of computer interface with the potential to transform interactions with surfaces in physical environments. They distinguish themselves from other visual output technologies, for instance LCD screens, by overlaying content onto the physical world. They can appear, disappear, and reconfigure themselves to suit a range of application scenarios, physical settings, and user needs. These properties have attracted significant academic research interest, yet the surrounding technical challenges and lack of application developer tools limit adoption to those with advanced technical skills. These barriers prevent people with different expertise from engaging, iteratively evaluating deployments, and thus building a strong community understanding of the technology in context. We argue that creating and deploying interactive projected displays should take hours, not weeks. This thesis addresses these difficulties through the construction of a toolkit that effectively facilitates user innovation with interactive projected displays. The toolkit’s design is informed by a review of related work and a series of in-depth research probes that study different application scenarios. These findings result in toolkit requirements that are then integrated into a cohesive design and implementation. This implementation is evaluated to determine its strengths, limitations, and effectiveness at facilitating the development of applied interactive projected displays. The toolkit is released to support users in the real-world and its adoption studied. The findings describe a range of real application scenarios, case studies, and increase academic understanding of applied interactive projected display toolkits. By significantly lowering the complexity, time, and skills required to develop and deploy interactive projected displays, a diverse community of over 2,000 individual users have applied the toolkit to their own projects. Widespread adoption beyond the computer-science academic community will continue to stimulate an exciting new wave of interactive projected display applications that transfer computing functionality into physical spaces

Telethrone : a situated display using retro-reflection basedmulti-view toward remote collaboration in small dynamic groups

This research identifies a gap in the tele-communication technology. Several novel technology demonstrators are tested experimentally throughout the research. The presented final system allows a remote participant in a conversation to unambiguously address individual members of a group of 5 people using non-verbal cues. The capability to link less formal groups through technology is the primary contribution. Technology-mediated communication is first reviewed, with attention to different supported styles of meetings. A gap is identified for small informal groups. Small dynamic groups which are convened on demand for the solution of specific problems may be called “ad-hoc”. In these meetings it is possible to ‘pull up a chair’. This is poorly supported by current tele-communication tools, that is, it is difficult for one or more members to join such a meeting from a remote location. It is also difficult for physically located parties to reorient themselves in the meeting as goals evolve. As the major contribution toward addressing this the ’Telethrone’ is introduced. Telethrone projects a remote user onto a chair, bringing them into your space. The chair seems to act as a situated display, which can support multi party head gaze, eye gaze, and body torque. Each observer knows where the projected user is looking. It is simpler to implement and cheaper than current comparable systems. The underpinning approach is technology and systems development, with regard to HCI and psychology throughout. Prototypes, refinements, and novel engineered systems are presented. Two experiments to test these systems are peer-reviewed, and further design & experimentation undertaken based on the positive results. The final paper is pending. An initial version of the new technology approach combined retro-reflective material with aligned pairs of cameras, and projectors, connected by IP video. A counterbalanced repeated measures experiment to analyse gaze interactions was undertaken. Results suggest that the remote user is not excluded from triadic poker game-play. Analysis of the multi-view aspect of the system was inconclusive as to whether it shows advantage over a set-up which does not support multi-view. User impressions from the questionnaires suggest that the current implementation still gives the impression of being a display despite its situated nature, although participants did feel the remote user was in the space with them. A refinement of the system using models generated by visual hull reconstruction can better connect eye gaze. An exploration is made of its ability to allow chairs to be moved around the meeting, and what this might enable for the participants of the meeting. The ability to move furniture was earlier identified as an aid to natural interaction, but may also affect highly correlated subgroups in an ad-hoc meeting. This is unsupported by current technologies. Repositioning of several onlooking chairs seems to support ’fault lines’. Performance constraints of the current system are explored. An experiment tests whether it is possible to judge remote participant eye gaze as the viewer changes location, attempting to address concerns raised by the first experiment in which the physical offsets of the IP cameras lenses from the projected eyes of the remote participants (in both directions), may have influenced perception of attention. A third experiment shows that five participants viewing a remote recording, presented through the Telethrone, can judge the attention of the remote participant accurately when the viewpoint is correctly rendered for their location in the room. This is compared to a control in which spatial discrimination is impossible. A figure for how many optically seperate retro-reflected segments is obtained through spatial anlysis and testing. It is possible to render the optical maximum of 5 independent viewpoints supporting an ’ideal’ meeting of 6 people. The tested system uses one computer at the meeting side of the exchange making it potentially deployable from a small flight case. The thesis presents and tests the utility of elements toward a system, and finds that remote users are in the conversation, spatially segmented with a view for each onlooker, that eye gaze can be reconnected through the system using 3D video, and that performance supports scalability up to the theoretical maximum for the material and an ideal meeting size