Telethrone: a situated display using retro-reflection based multi-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.