Exploitable results Virtually reconstructing the past Bringing ancient history to life challenges even the best of guides. Especially when the site is little more than a pile of crumbling stones. But research in Greece shows that a novel combination of audiovisual and communication technologies - turning reality into 'augmented reality' - can enhance visitor experience by rebuilding historical locations in front of their very eyes. In the run-up to the 2004 Olympic Games, it seems appropriate that Ancient Olympia in Greece should become the test site for a unique European initiative. Under ARCHEOGUIDE, a 34-month project that ended in October 2002, a consortium of seven partners from Greece, Germany, Italy and Portugal assembled innovative hardware and software solutions into three different types of interactive mobile device. Armed with any one of these units, fans of cultural heritage can now admire Olympia's architectural glories, as they looked several thousand years ago. The remains of once-grandiose temples - including foundations and colonnades - majestically develop automatically on-screen into complete virtual buildings as users approach. Audio commentary over headphones completes the historical picture. The ARCHEOGUIDE devices have already impressed one history teacher. "I toured Olympia with each of them and found the experience very compelling," recalls Ms Malliou, from the Ellinogermaniki Agogi private school in Athens. "Compared to a standard guide book, they offer visitors a different perspective and create a sense of wonder." She felt sure her own students would benefit from using such technology in their history lessons. But she hoped that future devices would be smaller and lighter than their present incarnations. More than technicalities The project's system calls on client-server architecture, comprising a site information server, mobile units and a communication infrastructure. The server stores all audiovisual and textual information about the site and its monuments. These data are accessed by the mobile units, which request information according to user preferences, position and the tour selected. Three mobile devices have been tested. The largest is based on a laptop computer, which users carry in a rucksack. The computer is linked to a D-GPS (differential global positioning system) receiver and digital compass, which together track the user's position and orientation. Also attached are a PC camera, capturing live video from the user's viewpoint, and an augmented reality (AR) head-mounted display (HMD). The HMD comes as a pair of see-through sunglasses, for viewing AR worlds. Added realism The system's clever part is the augmented reality. "AR systems have been studied for several years, but mostly in indoor environments," says Dr Vassilios Vlahakis, from INTRACOM, the Greek company responsible for the project's central server, network infrastructure and the integration of systems on the mobile devices. "Unlike virtual reality, where 3D models are projected onto a synthetic world, AR systems project 3D models onto a real background, seen with a user's eyes or a video camera that tracks the user's gaze." He adds with pride: "You are not cut off from reality by AR." The project tested several headset viewing devices. All of them change the image perspective as the user moves around the site. The second-generation glasses, similar to binoculars, were lighter and more compact than the original HMD and preferred by users such as Ms Malliou. She liked the ability to alter the transparency of the model "making it easy to compare the virtual reconstruction and the real scene." The two other units utilised, a tablet PC and palmtop computer, are smaller. They render 3D reconstructions of Olympia's ruins on their screens. Users interact with both by touching the screens, selecting data of interest or consulting a digital map to navigate around the area. Completing the system is the communication infrastructure. A wireless LAN, based on the IEEE 802.11 standard, transfers audiovisual content from the server to the mobile units. The second network facilitates user-tracking, by providing point-to-point wireless links from the D-GPS reference station to the mobile units' associated receivers. AR images were displayed at rates of around 15 frames per second. "This is satisfactory during normal head motion," says Vlahakis, "but a higher rate, ideally 30 frames/second, would be better during faster motion in order to achieve real-time display speed." The system was optimised for computing power rather than weight, mobility and robustness. "AR has only become possible in recent years, thanks to advances in chip and real-time graphics processing power," admits Vlahakis. Emerging technologies such as speech and gesture recognition will improve interactivity on future mobile units, doing away with the need for external input devices. This will help people with limited computer skills. Through data personalisation, users can select what they want to see or learn as they move around a site: a great way of avoiding information overload. Cartoon characters can be employed as information presenters in the display system, to hold children's attention. Imagine seeing the Olympic Games as they originally were, with avatar athletes competing against each other in the stadium of Olympia amongst spectators and real visitors. This too is possible with ARCHEOGUIDE. Features like these, believe the developers, will bring together the worlds of education, research and entertainment - making cultural visits a more enriching experience. Potential markets for ARCHEOGUIDE's expert personal guide system include museums, culture ministries and heritage sites. Its AR platform and components can find applications in industrial training, university education and mobile computing applications. Multimedia database technologies and data management can be applied to all industry sectors that handle large multimedia data volumes. More specifically in archaeology, the database and the authoring tools could help archaeologists plan excavations, perform virtual monument and artefact reconstructions and reuse multimedia content in other applications (e.g. tourist guide publishing). "We are actively searching out commercial partners and outlets," says Vlahakis, who adds that the project has aroused considerable interest from cultural heritage authorities in France, Italy, Portugal and the Middle East. Further demonstrations of the system - parts of which could also be employed on CDs and websites - are scheduled in Ancient Olympia, central Athens and elsewhere in the coming months. Promoted by the IST Results Service Searching for OpenAIRE data... There was an error trying to search data from OpenAIRE No results available
