Alonzo C. Addison, USA | ISBN: | Submitted: Jul 28, 1998

'Virtualized' Architectural Heritage-New Tools and Techniques for Capturing Built History

Virtual worlds have become common in computer graphics and entertainment, but in architecture and heritage applications historically accurate representations have remained elusive. Yet the potential is great-photorealistic walkthroughs and virtual representations offer researchers and the public a chance to transcend time and space and explore the past in a highly accessible form, to experiment with numerous interpretations or reconstructions without requiring physical intervention, and to enable low-impact visits by a truly global audience. despite an appreciation for their value. Although software tools, and standards such as VRML, for creating highly realistic 3D representations are now available, collecting accurate data has continued to hamper progress.

The representation of architectural heritage requires two distinct forms of 3D data-current, real world conditions, and virtual or 'theorized' historical interpretations. We call the combination of the two forms 'virtualized' as opposed to 'virtual'.

New technologies have recently emerged which show great promise for architectural heritage applications. At the 8th-10th century church of the Pomposa Abbey near Ferrara, Italy, we utilized a variety of methods to document existing conditions as a basis for a 'virtualized' representation of the church's presumed state centuries ago. Starting with a hand survey, the Ferrara team went on to use a theodolite and photogrammetric camera to capture existing 3D conditions of a structurally failing facade. In cooperation with NRC Canada, a handheld short range Biris scanner was used to capture 3D surface geometry of several stone reliefs at submillimeter accuracy. In a second project at the US landmark Hearst Memorial Mining Building in Berkeley, California we utilized a 100-meter range prototype 3D laser radar scanner from Cyra Technologies to record the existing state of the facade prior to a major earthquake renovation. In both of these cases, three dimensional data collection technologies, coupled with historic research, allowed the creation of 'virtualized' worlds for analysis, visualization, and simulation of current, as well as past, conditions. In the coming year we hope to take these capture and associated modeling and reconstruction techniques further in planned projects on World Heritage Sites in Rome and Peru.

New three dimensional survey and measurement technologies, from the close range scanner utilized at the Pomposa Church to the large object lidar scanner utilized at Berkeley, allow significantly faster and more accurate documentation of real-world conditions. 'Virtualized' architectural heritage offers the research community and greater public the possibility to quickly and accurately document our past for future generations.

Further images and details about this paper and work can be found at: http://dns.unife.it/architettura/labs/OFF/Pomposa_Berkley/pag1.htm http://dns.unife.it/architettura/labs/OFF/Pomposa_Berkley/pag2.htm

[more information]

[other authors]
Marco Gaiani

[keywords]
architectural heritage, virtual reality, photogrammetric camera, 3D, 3D laser radar scanner