5 research outputs found
Outdoor Augmented Reality: State of the Art and Issues
International audienceThe goal of an outdoor augmented reality system is to allow the human operator to move freely without restraint in its environment, to view and interact in real time with geo-referenced data via mobile wireless devices. This requires proposing new techniques for 3D localization, visualization and 3D interaction, adapted to working conditions in outdoor environment (brightness variation, features of displays used, etc.). This paper surveys recent advances in outdoor augmented reality. It resumes a large retrospective of the work carried out in this field, especially on methodological aspects (localization methods, generation of 3D models, visualization and interaction approaches), technological aspects (sensors, visualization devices and architecture software) and industrial aspects
3D Multi-user interactive visualization with a shared large-scale display
When the multiple users interact with a virtual environment on a largescale
display there are several issues that need to be addressed to facilitate the
interaction. In the thesis, three main topics for collaborative visualization are
discussed; display setup, interactive visualization, and visual fatigue. The
problems that the author is trying to address in this thesis are how multiple
users can interact with a shared large-scale display depending on the display
setups and how they can interact with the shared visualization in a way that
doesn’t lead to visual fatigue.
The first user study (Chapter 3) explores the display setups for multi-user
interaction with a shared large-display. The author describes the design of the
three main display setups (a shared view, a split screen, and a split screen with
navigation information) and a demonstration using these setups. The user
study found that the split screen and the split screen with navigation
information can improve users’ confidence and reduce frustration level and
are more preferred than a shared view. However, a shared view can still
provide effective interaction and collaboration and the display setups cannot
have a large impact on usability and workload.
From the first study, the author employed a shared view for multi-user
interactive visualization with a shared large-scale display due to the
advantages of the shared view. To improve interactive visualization with a
shared view for multiple users, the author designed and conducted the second
user study (Chapter 4). A conventional interaction technique, the mean
tracking method, was not effective for more than three users. In order to
overcome the limitation of the current multi-user interactive visualization
techniques, two interactive visualization techniques (the Object Shift
Technique and Activity-based Weighted Mean Tracking method) were developed and were evaluated in the second user study. The Object Shift Technique translates the virtual objects in the opposite direction of movement
of the Point of View (PoV) and the Activity-based Weighted Mean Tracking
method assigns the higher weight to active users in comparison with
stationary users to determine the location of the PoV. The results of the user
study showed that these techniques can support collaboration, improve
interactivity, and provide similar visual discomfort compared to the
conventional method.
The third study (Chapter 5) describes how to reduce visual fatigue for 3D
stereoscopic visualization with a single point of view (PoV). When multiple
users interact with 3D stereoscopic VR using multi-user interactive
visualization techniques and they are close to the virtual objects, they can
perceive 3D visual fatigue from the large disparity. To reduce the 3D visual
fatigue, an Adaptive Interpupillary Distance (Adaptive IPD) adjustment
technique was developed. To evaluate the Adaptive IPD method, the author
compared to traditional 3D stereoscopic and the monoscopic visualization
techniques. Through the user experiments, the author was able to confirm that
the proposed method can reduce visual discomfort, yet maintain compelling
depth perception as the result provided the most preferable 3D stereoscopic
visualization experience.
For these studies, the author developed a software framework and designed
a set of experiments (Chapter 6). The framework architecture that contains
the three main ideas are described. A demonstration application for multidimensional
decision making was developed using the framework.
The primary contributions of this thesis include a literature review of multiuser
interaction with a shared large-scale display, deeper insights into three
display setups for multi-user interaction, development of the Object Shift
Techniques, the Activity-based Weighted Mean Tracking method, and the
Adaptive Interpupillary Distance Adjustment technique, the evaluation of the
three novel interaction techniques, development of a framework for
supporting a multi-user interaction with a shared large-scale display and its
application to multi-dimensional decision making VR system
Language-level support for exploratory programming of distributed virtual environments
We describe COTERIE, a toolkit that provides languagelevel support for building distributed virtual environments. COTERIE is based on the distributed data-object paradigm for distributed shared memory. Any data object in COTE-RIE can be declared to be a Shared Object that is replicated fully in any process that is interested in it. These Shared Objects support asynchronous data propagation with atomic serializable updates, and asynchronous notification of updates. COTERIE is built in Modula-3 and uses existing Modula-3 packages that support an integrated interpreted language, multithreading, and 3D animation. Unlike other VE toolkits, COTERIE is based on a set of general-purpose parallel and distributed language concepts designed with the needs of virtual environments in mind. We summarize th