Optical Camouflage - Review

Fiber optic systems are important telecommunication infrastructure for world-wide broadband networks. Wide band width signal transmission with low delay is a key requirement in present day applications. Optical fibers provide enormous and unsurpassed transmission bandwidth with negligible latency, and are now the transmission medium of choice for long distance and high data rate transmission in telecommunication networks. This paper focused on the creation of invisibility with the help of technologies like Optical camouflage Image based rendering and Retro reflective projection. The object that needs to be made transparent or invisible is painted or covered with retro reflective material. There are some beneficial applications for this simple but astonishing technology. The different methods of optical camouflage provide invisibility in the visible site of spectrum. One of the most promising applications of this technology, however, has less to do with making objects invisible and more about making them visible. nbs

A mixed reality telepresence system for collaborative space operation

This paper presents a Mixed Reality system that results from the integration of a telepresence system and an application to improve collaborative space exploration. The system combines free viewpoint video with immersive projection technology to support non-verbal communication, including eye gaze, inter-personal distance and facial expression. Importantly, these can be interpreted together as people move around the simulation, maintaining natural social distance. The application is a simulation of Mars, within which the collaborators must come to agreement over, for example, where the Rover should land and go. The first contribution is the creation of a Mixed Reality system supporting contextualization of non-verbal communication. Tw technological contributions are prototyping a technique to subtract a person from a background that may contain physical objects and/or moving images, and a light weight texturing method for multi-view rendering which provides balance in terms of visual and temporal quality. A practical contribution is the demonstration of pragmatic approaches to sharing space between display systems of distinct levels of immersion. A research tool contribution is a system that allows comparison of conventional authored and video based reconstructed avatars, within an environment that encourages exploration and social interaction. Aspects of system quality, including the communication of facial expression and end-to-end latency are reported

Gametecture: architectural form in augmented reality

Architectural forms of the digital age are based on games and computer simulations: formation, information, transformation. Formation means creation of structures as extensions of the kinetic potential of the human body (form as skin or wrapper). inFormation is based on the active power of information (interactive and intelligent structures). transFormation means sequences of forms as mutations of primary structures in topological space (metamorphic forms)

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

A 3D image-based measurement approach for analysing dynamic foot posture and mobility

The original contribution achieved from this research was the development of a low-cost 3D high-accuracy photogrammetric technique for measuring dynamic changes in foot anthropometry during gait. In clinical settings, the approach of determining foot mobility is achieved through measuring changes in bone landmarks between the static unloaded foot and the static loaded foot. From previous reliability assessment tests, it was found that static clinical foot mobility assessments based on the dorsum bone as a point of landmark reference provides high levels of measurement reliability. However, the relationships between these static dorsum measurement techniques have not been assessed against dynamic dorsum measurements collected during foot mobility. In this thesis, two assessment techniques based on the dorsum as a point of reference; namely the Foot Mobility Magnitude (FMM) and Arch Height Index (AHI) were compared statically and dynamically. The purpose for this was to validate these static measurements against the actual foot mobility during dynamic activities. An imaging platform was developed which consisted of 12 video cameras synchronised with force plate data to continuously capture the foot during gait while simultaneously obtaining ground reaction force information. The developed system achieved measurement accuracies within 0.3 mm with high levels of measurement precisions and insignificant random and systematic errors. From the research study, it was found that the correlation between the static and dynamic FMM measurements was insignificant, whereas significant correlations were found between the static and dynamic AHI measurements. Agreements between the static and dynamic AHI measurements were higher when the dorsum measurements were normalised to the truncated foot length (AHI 1) than normalising the dorsum measurements to the total foot length (AHI 2). Another major finding from the research was the higher measurement correlations achieved when the dynamic FMM and AHI were assessed between heel-strike and mid-stance compared to between heel-strike and active propulsion. This indicates that measuring the static FMM and AHI between 10% WB and 50% WB instead of between 10% WB and 90% WB might lend better insight in determining the behaviour of the foot dynamically. The Foot Posture Index (FPI) was used to classify foot postures and the relationship between the FPI scores and the dynamic FMM and AHI were assessed. It was found that the FPI was significantly correlated to the AHI measures but no correlation was found between the FPI and the FMM. The highest correlation was found for AHI 1 at active propulsion where the FPI predicted 48.9% of the variation of the AHI 1. The only FPI classification criteria to have a significant influence on the AHI at heel-strike, mid-stance and active-propulsion was the congruence of the MLA with the highest prediction of 66.7% of the variation in the AHI 1 at heelstrike