How 3D Laser Scanning is Helping Restore Ancient Buildings
Building Information Modelling, or BIM, is a relatively recent innovation that has transformed the construction industry. BIM is a term used to describe the process of creating and managing information on a construction project across that project’s lifecycle. Experts apply it to the construction of new buildings and structures, with the life cycle spanning everything from conception to demolition.
Elements such as 3D scanning, can help record, uphold, and preserve older existing buildings. It might be a modern technique, but it’s helping to maintain important structures from the past.
What is 3D scanning?
3D scanning uses lasers aimed at various points of a building, structure or site. These lasers, which pulse thousands of times per second, give incredibly exact measurements between points, creating a 3D collection of XYZ coordinates known as a point cloud.
The point cloud represents the raw data of a survey, but specialist software can convert this data into comprehensive 3D site models. These can aid in the design and construction process to help plan the details of a new structure. In the fields of restoration and heritage, they can also record spatial and physical information about a building or help conservationists pinpoint issues and find solutions.
3D scanners used on the ground may be either fixed (tripod-mounted) or handheld. In architectural projects, airborne scanning can take place from an aircraft. This is known as Light Detection and Ranging, or LIDAR.
Creating a 3D architectural archive
Digital preservation is a new concept in heritage and archaeological disciplines. It uses 3D scanning in conjunction with digital film and photography to build a complete representation of a site or structure. This allows archaeologists not only to view the site as it is but also to digitally reconstruct how it would have looked hundreds or thousands of years ago.
CyArk is a non-profit organization aiming to create a comprehensive digital record of the world’s historic sites. It has already utilized laser scanning to survey sites such as Mount Rushmore, the medieval St Sebaldus Church in Germany, and the ancient Mayan city of Chichen Itza in Mexico.
The Vice President of CyArk Elizabeth Lee told technology website Gizmodo: “I would say we’re bringing a huge change to both archaeology and general heritage management. We like to think about what we’re doing — this idea of digital preservation — as kind of a paradigm shift for the entire field.”
She continued: "Once you have that information, you can do all sorts of things with it. You can slice through the building, create a video animation, bring parts of that data into a CAD design program for drawings and manipulations, develop virtual tours, make highly accurate models."
Restoration projects
The Castle of Coatfrec in Brittany is another site that involves digital archaeology, but in this case, digital scans also helped in the physical restoration process. A combination of 3D scanning, modeling, and analysis charted the structures that were still standing and used these to judge their structural and physical relationships to now-absent elements.
Historic England (formerly known as English Heritage) has also started to make extensive use of laser scanning. As with CyArk, the organization uses digital scans to archive and increase understanding of historical sites and said that this can be particularly useful “where a feature, structure or site might be lost or changed forever, such as in an archaeological excavation or for at a site at risk”.
It also said that 3D scanning can work in physical conservation and restoration programs, helping to check structural and physical conditions and analyzing the effects of weather, pollution, footfall or vandalism. This allows conservationists to put relevant measures in place and involves making replicas of areas or items using digital information. These replicas can be viewed in place of the original artifacts or set within a structure as part of the restoration process.
It’s no secret that 3D scanning has a large part to play in the design of new buildings. It can even help them become more sustainable moving forward. With a wide variety of applications, including preserving and recreating structures from the past, it’s safe to say that technologies like 3D scanning will continue to be utilized and built upon over time.