Digital technologies and AI at the bedside of world architectural heritage

Where Eugène Viollet-Le-Duc (1814-1879) carried out his surveys by hand and undertook tedious plaster casting campaigns to restore Notre-Dame, architects and heritage specialists now have access to highly precise digital duplicates of the masterpiece of Gothic art, devastated by a fire in 2019.

Thanks to images taken by drones and in-situ measurements from laser scanners, "the 3D model accurately reproduces the monument and all its deformations and imperfections, like an X-ray for the human body," Frédéric Gourdet, project manager for the Valorisation project at the French company AGP (Art graphique & Patrimoine, Memorist group), founded in 1994 and a pioneer in digital technologies for cultural heritage, told AFP.

For Notre-Dame, "we were able to compare the before and after fire, a gold mine," he adds.

AGP, which had carried out surveys of the framework before the fire, digitized a large part of the cathedral the day after the disaster and its entirety a few weeks later.

Digital twin

The development of a "digital twin of the cathedral, or intelligent 3D model, then made it possible to diagnose, study and reconstruct the building thanks to the production of graphic, metric and structurally fragile documents," explains Mr. Gourdet.

Essential for installing scaffolding and positioning cranes, this digital double also made it possible to study the resistance of the cathedral's spire to wind, Emmanuel Di Giacomo, head of building information modeling (BIM) and AI for architecture in Europe at Autodesk, an American company that publishes digital creation and content software, and which is associated with AGP at Notre-Dame, explained to AFP.

"Generative AI (content producer) allowed us to simulate the entire construction process, saving considerable time by generating suggestions. Each of the cathedral's 189 vaults, for example, was digitally recreated, like the elements of the framework that were transported by barge on the Seine, so that we could arrange and assemble them like a sort of giant Lego, in a strict order," he explains.

The American company, which will provide the official design and manufacturing platform for the Los Angeles 2028 Olympic Games, is focusing on even more innovative solutions "by restoring existing heritage rather than building new structures," according to this official.

Pyramids, basilica, mosque

The use of AI is also "revolutionizing" the practices of the French company Iconem, which carried out "the first high-resolution scan of the Egyptian pyramids at Giza," its co-founder, Yves Ubelmann, told AFP.

"We use AI for very large-scale calculations and the restitution of reality as it is - deteriorated or not - it is the basis for reconstructing the previous states of monuments and heritage sites. It is also a valuable scientific tool for the conservation, management and protection of artistic and architectural heritage," he adds.

Iconem has reconstructed the entirety of St. Peter's Basilica in Rome, including its Roman necropolis, the subject of an immersive exhibition.

She also created a virtual model of the very first Angkor site in Cambodia that the public will be able to discover in a museum due to open in 2026 in Siem Reap.

In war zones, it also digitized the al-Nouri mosque in

Mosul (Iraq), reduced to ashes in 2017 then restored with UNESCO, the

site of Palmyra in Syria and the cities of Aleppo and Beirut, "territories

whose data was threatened with disappearance," explains Mr. Ubelmann.

Today, he adds, "AI software is trained to

observe areas to be protected" using satellite imagery.

Looting of archaeological sites has thus been detected recently.

in northern Afghanistan, according to the official.

Microsoft, the International Alliance for the Protection of Heritage in

conflict zone (Aliph), Iconem and Planet Labs, American image provider

satellites, launched an endowment fund, "HeritageWatch.AI" in February

to, they assure, map the world heritage and anticipate the

risks that threaten it.