Designing and Implementing a Context-Aware Augmented Reality System

Over time, spatial data has evolved from paper maps to Web GIS through digital mapping and finally to the current generation of GIS. Although this new interface has enhanced user’s insights about spatial information, it still needs more tangible interface that can be usable to the public and enhance human interactions with the environment and spatial objects. Combining real and virtual worlds, Augmented Reality (AR) systems can make more tangible experience with real world objects. These activities relies on the dynamic working environments. Therefore it is important to consider the users environment and its changing through context-awareness. Context-awareness is any kind of information about user’s status and its estimation allows to integrate the context with the happening changes. AR is a combination of real vision with virtual content in real–time and acts as an interface to increase user insight of the real world and interaction with it. With increasing information in the AR, the usefulness and readability of information decreases and the details and their display should also be subject to certain conditions. To overcome this problem, we offer the combination of AR with context-awareness. Hence, in this study, The AR representation varies according to the user’s context. The increasing use of sensors, their hardware and software enhancements, and growth and development of communication networks have led to development of context-aware computing. Context-aware computing is rooted in processing anywhere and anytime, and aims at understanding environmental changes in computer systems so that computers can understand and respond to their environment. The small screen, low bandwidth, interaction problems, and user’s quick need to obtain response from service have driven services to provide information based on users and their environments. Nowadays, in most location planning applications, they try to use directional data besides location data. By using this information, better interaction and information are provided to user. The activities performed depend on user’s dynamic work environment, so by using context-aware knowledge, the environment and user environment changes receive more attention. The output of old programs was based on specific input and did not consider context change.
By increasing the amount of realistic information, simultaneous provision of all information will not only reduce the usefulness and readability of information, but also details and their presentation. In order to overcome the problem, we have used a context-aware augmented reality that displays the necessary information according to actual increase in user’s context. Specially in the domain of spatial services, given the massive amount of the available information and simultaneous provision of data in real-time due to small display of associated equipment make visual distraction for user, so by using context-awareness, useful and proper information can be provided to the user. Having the vulnerability maps, specifically about buildings in the region of interest is a necessary requirement for any rescue and relief teams after earthquake. Due to the lack of immediate access to earthquake vulnerability maps, it is necessary to provide an intelligible context information system for displaying vulnerabilities of building with the help of augmented reality. In general, any type of navigation issue, information about building vulnerabilities to select safe paths or temporary accommodation is required. In order to implement such information system, three contexts, i.e. distance, direction and time for presenting information in augmented reality was studied. To this purpose, after zoning vulnerability caused by earthquake in Tehran, Donyaye-Noor business complex was used as the case study and information system was considered with three contexts for given site. In order to evaluate the presented system, our context-aware augmented reality system was compared with an augmented reality system alone.
Results of evaluation show that combination of augmented reality and context-aware can reveal suitable information by considering the user context, while data presentation in augmented reality is monotonic and there is no dynamism in changing information display. The results of evaluating combined augmented reality system with context-awareness compared with augmented reality alone show that context-aware augmented reality system is more active and always reveals more adopted information to the user regarding environmental dynamics. While information is uniform and does not change in augmented reality.
Using the context-aware spatial information system, the user can take different decisions under different circumstances or gain extra information about other context such as time, velocity, acceleration. To better understanding augmented reality, certain graphical forms can be used. Displaying vulnerability by augmented reality can be a tool for ordinary users or specialists in the field of urban design and management, without the need for mapping and map reading knowledge in managing important centers and building in low-risk areas. The results of integrated system evaluation from various users indicate the system’s performance is superior to augmented reality system alone.