Demonstrating the use of the alphabetic telegraph through a collaborative AR activity Iason Panagiotis Diakoumakos Department of Informatics and Telecommunications National and Kapodistrian University of Athens Athens, Greece sdi1100009@di.uoa.gr Akrivi Katifori, Vassilis Kourtis, Manos Karvounis, Yannis Ioannidis Athena Research Center Athens, Greece {vivi, vkourtis, manosk, yannis}@di.uoa.gr Abstract—Augmented reality (AR) has been extensively used in different contexts, including tourism and cultural heritage, in both commercial and research applications, and they are well known for their ability to capture the attention of their potential users. On the other hand, collaboration among groups in a museum context is proven to engage the visitors and offer a more personal experience. The combination of these two technics has not yet been thoroughly explored. In this work, we present a card-based AR application with the objective to engage the visitors in a collaborative activity designed to showcase on-site the use of a 19th century‟s alphabetic telegraph, exhibited in the History Museum of the University of Athens. The users are able to manipulate photorealistic 3D models that simulate the operation of the telegraph transmitter and receiver and use them to send messages to one another. The application has been evaluated with 19 pairs of teenage students with very promising results. Keywords—augmented reality, collaborative experience I. INTRODUCTION Augmented reality (AR) has been extensively used in different contexts, including gaming, sports, marketing, commerce, even military applications and it has been gradually being turned into a common technological approach accessible even to the wider public through devices like their mobile phones. Tourism and cultural heritage has been a field where AR has been applied in both commercial and research applications, and has been a major focus and research direction in projects like Mesch 1 and CHESS 2 . Collaboration among groups in a museum context has also been proven to engage the visitors and offer a more personal experience. People typically visit museums and heritage sites in social groups, either in conjunction with organized parties, or with family or friends [1][3]. The value of social interactions taking place in such visits has long been recognized as important in museum studies [2][4], and a growing line of research now focuses upon digital technologies as means to enhance this social context [5]. The combination of these two technics, AR and collaboration, in a cultural heritage context is an approach that 1 http://www.mesch-project.eu/ 2 http://www.chessexperience.eu/ has not yet been thoroughly explored. In this work we present a collaborative AR application with the objective to engage the visitors in a common activity designed to showcase on site the use of the alphabetic telegraph, exhibited in the History Museum of the University of Athens. Section II offers an overview of related approaches in the field of cultural heritage, whereas Section III presents the objectives of this work, IV provides implementation details and V the evaluation details. Section VI concludes the paper. II. AR IN CULTURAL HERITAGE AR may offer different views of an artefact or cultural site, visualizing its original state or different states of its preservation and thus providing to the visitor a more in depth view of the artefact. An example of an AR application on a 3D exhibit with the purpose to present its original state has been the one developed in the context of the EU funded project CHESS and presented in [6]. The visitors were offered the possibility to view status of Ancient Greek women (“Korai”) through their mobile device and see them in their original colourful state. They also could interact with the augmented view of the statue and listen to information for specific details and parts that were not directly evident or visible in the original statue. Mesch also explored the use of AR in a museum context [7] by experimenting with its use removing the intimidating association in the example of a pilot that run in the Allard Pierson Museum. The museum made use of iPhones in a purpose-built case in the shape of a loupe or magnifying glass so that visitors could hold the device with one hand. Any association with a specific device or technology was removed to avoid that visitors automatically try a fixed gesture vocabulary. The loupes were presented hanging from a display, directly connected with the objects. Visitors saw the outline of the object they had to look for and had to tilt the loupe in order to move on and see new content. As already mentioned, our approach attempts to introduce a new aspect into the use of AR in this context, that of collaborative applications. Our hypothesis was that bringing the visitors together in a common task, which directly and interactively showcases the use of an actual exhibit, would enhance their engagement with the object and their