Donations close to a billion dollars are pouring in from across the globe for the restoration of 850-year-old medieval Catholic cathedral Notre-Dame de Paris which was undergoing renovations at the time of the fire. While investigating agencies are hard at work to decipher the cause that might have turned one of the finest examples of French Gothic architecture into an inferno, French authorities have announced that they want Notre-Dame rebuilt in five years.
Considering the complexity and pressure to deliver the project close to its original design and feel, five years to rebuild one of the most recognized symbols of the French nation may not seem to be a lot to ask considering the fact its initial construction began in 1160 and was largely completed by 1260, followed by several modifications and alterations in following decades.
However, one may argue that with so many technological advancements and evolution of overall construction industry, can’t these latest technologies help to rebuild and reopen the most-visited monument in Europe to over 12 million visitors a year sooner with its original design and feel?
Design Accuracy and Precision is Everything
One of the biggest challenges in rebuilding the cathedral is to get the design accurate and truly precise to its original version. Using traditional methods would take a long time and may not be precise or accurate, particularly in the case of unique details resulting in rework and inefficiencies. This is where the latest technologies and advancements like Artificial Intelligence (AI), laser scanning, photogrammetry, and Building Information Modeling (BIM) can help and play a vital role.
With photo-to-point cloud creation or laser scanning, we can gather millions of points simply by camera-equipped unmanned aerial vehicle (UAV), hand-held device, or laser scanning device. We can also create photo-textured meshes, photo-based point clouds with geolocation, and high-resolution orthographic views with elevation maps. Through automation and the computing power of the cloud, the software is speeding up and automating the once tedious process of registering (stitching) and editing captured information.
Finally, we can combine these captured data from all the sources, if needed with an amazing level of detail. This combined digitised 3D model mapped onto an XYZ coordinate system, providing a more intelligent survey output to export for use. By facilitating the creation of highly accurate virtual models that can be imported and used to further develop/convert into a Building Information Model teams can deliver the project with accurate execution of the design vision.
Let us look at the example of the ancient city, Volterra in Italy, built over 3,000 years ago with historic sites dating back to the 4th century BC. In 2016, an international team of architects, engineers, historians, and students embarked on a journey to digitally reconstruct many of the historically significant architectural treasures of this ancient city.
They used innovative technologies including drones, photogrammetry, and laser scanning reality capture techniques, together with Autodesk ReCap 360 software, to digitally record and produce spectacular photo-realistic virtual replicas which may be used to share the experience of the city to anyone in the world and for the city to have precise documentation for potential future reconstruction. The project consisted of three phases; digitally recreating historical and archaeological artifacts, creating Building Information Models of historic buildings and architectural features, and creating 3D interactive models of ancient historical sites.
Research at Volterra-Detroit Foundation
In the case of Notre-Dame, apart from the ancient official blueprints of the design, a gaming company have announced they have also got a 3D scan of the infrastructure which they recorded in the process for one of their games. Also, authorities may also want to consider reaching out to the millions of the tourists who have visited the monument in the past and request to share any photographs to feed the intelligent automated and cloud-powered software for the tedious process of registering (stitching) and editing captured information. Finally, combine these captured data from all the sources to develop a Building Information Model as “Single Source of Truth” of the original design with very high accuracy and precision.
This not only will save time and effort to build an accurate and precise design, but the design can be verified and validated way before the shovel hits the ground; not to mention getting the authorities and public involved and approvals faster. Finally, this approach will give an exceptional opportunity to reproduce every corner and detail of this historical and cultural heritage that is unique and unrepeatable characteristics precisely as it was before.
The assets like Notre-Dame Cathedral, are not only important to a country but to whole humankind, as it is evident by the reach out from various countries, companies, and individuals offering to help. I am proud our company Autodesk and CEO Andrew Anagnostalso have offered to help.
“Autodesk will be contributing money to the restoration fund and our expertise and software to the restoration efforts,” he said. “May the beauty and majesty of Notre-Dame grace the skyline of Paris for many generations to come.”