Extending Augmented Reality Mobile Application with Structured Knowledge from the LOD Cloud Bet ¨ ul Aydin Grenoble Informatics Lab. 681, rue de la Passerelle 38402 Saint Martin d’H ` eres France Betul.Aydin@imag.fr J´ erˆ ome Gensel Grenoble Informatics Lab. 681, rue de la Passerelle 38402 Saint Martin d’H ` eres France Jerome.Gensel@imag.fr Philippe Genoud Grenoble Informatics Lab. 681, rue de la Passerellem 38402 Saint Martin d’H ` eres France Philippe.Genoud@imag.fr Sylvie Calabretto INSA de Lyon 20, avenue Albert Einstein 69621 Villeurbanne Cedex France Sylvie.Calabretto@liris.cnrs.fr Bruno Tellez Claude Bernard Uni. Lyon 1 43 bvd du 11 Novembre 1918 69622 Villeurbanne Cedex France Bruno Tellez@liris.cnrs.fr ABSTRACT ARCAMA-3D (Augmented Reality for Context Aware Mo- bile Applications with 3D) is a mobile platform that allows us to overlay a 3D representation of the surroundings with augmented reality objects. In this paper, we show how these 3D objects, which are overlaid on the real view captured by the camera of the mobile device, are coupled with the Linked Open Data (LOD) cloud. With this approach, the data ag- gregation for a mobile augmented reality system is provided using the interconnected knowledge bases on the Web. This offers the possibility to enrich our 3D objects with struc- tured information on the cloud. The objects that act as an augmented reality interface are used to provide an interac- tive access to these information. This approach provides an opportunity for people who publish information on the LOD cloud to interlink their data with 3D urban models. In order to achieve this, we propose an extensible data model that takes into account the temporal evolution of real world en- tities (such as buildings, monuments, etc.) and we publish our 3D models using this data model. 1. INTRODUCTION Ubiquitous mobile applications rely on context and loca- tion aware approaches in which the system takes into ac- count the changing context of the user to provide informa- tion dynamically. However, constraints related to the small displays of mobile devices and the methods used in order to look for information during the mobility require providing the most relevant information when the user expects a quick answer. For example, in order to discover the surroundings using a mobile application, the systematic and exhaustive presentation of all Points of Interest (PoIs) will not only hamper the readability of these collected information, but also risk to divert the user who observes her surroundings. In this paper, we present a context-aware Augmented Re- ality (AR) approach which minimizes the effort from the user to access and interact with the information that may be of her interest. For this, we interconnect our applica- tion with the Linked Open Data [8] which, by structuring the knowledge available on the Web, enables a semantic ap- proach in the information search and discovery. Augmented reality consists in an interactive medium that overlays the real world with some objects modelled in 3D and keeps their alignment in real time [3]. By adding a virtual layer on the real world view, the goal is to improve and enrich the user’s perception. LOD uses the infrastructure of the World Wide Web to publish and link datasets that can then be explored and ex- ploited by applications accessing to them. While achieving some of these objectives still remains a research interest, many datasets from very different domains (media, biology, chemistry, economics, energy, etc.) are already published and are constantly being enriched. A portion of these data contains geo-localized information that can be exploited by the applications, especially while the user is moving. How- ever, few mobile augmented reality applications have ex- plored this possibility. ARCAMA-3D (Augmented Reality for Context Aware Mo- bile Applications with 3D) [1], [2], our AR system, superim- poses transparent 3D representations of the real world ob- jects, with which the user can interact, on the view captured by the mobile device, such as a smartphone. By enriching the 3D models with thematic and temporal metadata pub- lished on the LOD cloud, ARCAMA-3D proposes answers to several applicable ubiquitous scenarios in which the aug- mented reality interface effectively helps the user during her exploration of the real world based on her choices and pref- erences. The paper is organized as follows. In Section 2, we present some work that integrates a location-based approach in an 1 Proceedings IMMoA’13 21 http://www.dbis.rwth-aachen.de/IMMoA2013/