Drones and robots helping save Paris Notre Dame Cathedral

In the era of social networks, events such as the fire at Notre Dame Cathedral are watched by a global audience in real time. From New York to Tokyo, millions of people stuck to their smartphones and computers, waiting for the latest updates from the media and individuals who documented the fire from the scene. Twelve harsh hours, the fate of the 850-year-old icon of Paris hung in the balance, and for some time it seemed that the worst could not be avoided.

The fire was completely extinguished, the smoke cleared, and in the light of day, we find out what heroic accomplishments the rescue services had to go to avoid a complete disaster. And although the cathedral suffered serious damage, its structure and most of the priceless works of art have been preserved. It is too early to assess how much it will cost to clean and repair the cathedral, but even the most optimistic estimates speak of hundreds of millions of dollars. In the case of such an old structure, its reconstruction is likely to slow down due to the fact that historians will have to re-examine the construction technologies that have been used over the past centuries and outdated to this day. But the people of France will not scare it away, and President Macron has already promised that his country will restore the cathedral in five years.

It is impossible to overestimate the importance of the actions of men and women who risked their lives to save one of France’s favorite monuments. They deserve praise from the grateful people of the country and the world. But along with them, advanced technologies also fought, some of which went to service immediately after notification. These vehicles helped guide firefighters in their battle against the raging flames, and replaced the man in case of too much risk. As a result, it was not cars, but people, that dealt with the fury of nature; but if not for the application of modern technology, the damage could have been much stronger.

Top view

As the French media wrote , the rescue services used at least two drones to inspect the burning cathedral. Thanks to the images obtained, firefighters could observe the intensity and movement of the fire in real time. Using drones was not only faster and cheaper than helicopters - their operators could fly much closer to the fire, because they were not so afraid of fire and smoke as a manned aircraft that would keep a respectful distance from the fire.


Mavic pro

However, it turned out that the Parisian firefighters did not actually have their drones for use in such situations. They occupied two copies available for sale, which were used by the Ministry of the Interior and the Ministry of Culture. Both models of quadrocopters, Mavic Pro and Matrice M210, are made by the Chinese company DJI. The products of this manufacturer practically represent the segment between consumer and professional platforms for aerial photography [prosumer - from professional (professional) and consumer (consumer) / approx. trans.], and also this company produces the extremely popular Phantom series of drones.

The Mavic Pro is a small semi-autonomous quadrocopter that DJI advertises as the ideal device for spontaneous shooting of high-quality video, because it can be folded up, making it much easier to transport than traditional quadrocopters. Its flight time is up to half an hour, the camera with a resolution of 4K has a gimbal for three-axis stabilization, and it also can automatically track objects selected by the operator in the frame and rotate around them - as a result, it was ideally suited for viewing fire from above.


Matrice M210

Unlike the Mavic, the Matrice M210 belongs to the DJI professional quadrocopter line. It is larger and more powerful, and is designed to carry payloads such as spotlights, thermal imagers, and cameras with optical zoom. There are conflicting messages about whether a thermal imager was installed on the M210 used by Parisian firefighters, but in any case, he still gave them another high-definition video source.

It is interesting to note that in general it is strictly forbidden to use drones in Paris , and the support function of "geographical barriers" built into DJI products would not allow them to fly over Notre Dame. However, the DJI system allows operators to send requests to temporarily remove restrictions, which allowed the manufacturer to quickly work together with the French authorities and allow flights of drones due to the seriousness of the situation.

On the shoulders of the Colossus

If consumer equipment coped with its task in the sky, then on earth the situation was too complicated for beginners. To penetrate the cathedral and try to fight the fire from within, Parisian firefighters used the Colossus. This 500 kg tracked platform , developed by Shark Robotics, is essentially fireproof and waterproof, and coupled with a motorized water cannon is a powerful fire fighting asset.

The Colossus was especially useful during the extinguishing of a fire in Notre Dame, as it could remain inside the structure when the roof was already enveloped in fire. When burning debris fell from above, and then the inevitable collapse of the cult spire of the building, consisting of lead and wood, the inside of the cathedral was a particularly dangerous place for live firefighters. The Colossus was able to provide a constant water flow in the nave, even when the entire building literally fell apart into parts around it. The final cooling effect has already been called the main factor, thanks to which it was possible to save priceless stained-glass windows. In addition, he gave the firefighters another real-time video stream, and they were able to determine a safe moment when additional commands could be sent inside.

High tech recovery

Advanced technologies and robots played a role in saving the cathedral, and, apparently, their work is not over yet. As we saw during previous disasters, for example, the accident at the Fukushima nuclear power plant , robots can be used to study structural integrity in places too dangerous for humans. From the air, drones with high-resolution cameras will be able to quickly obtain images of the entire structure, and this can help in creating a three-dimensional model of the building using photogrammetry ; it will be possible to design a modern roof that blends with the original masonry.

For the restoration of Notre Dame in such an ambitious period as five years, set by President Macron, without neglecting the safety of the thousands of workers who will be involved in this project, no help options will be rejected. The French people are excited by this event, and before the end of this project, we may still see new advanced solutions specially designed to overcome the unique difficulties associated with this reconstruction. The fire in Notre Dame can be called a historical tragedy, but the lessons we have learned can bring such benefits to the world that it’s even hard to imagine today.