Mapping the ocean floor with a swarm of underwater drones

Start-up DEESS won the Octo’pousse innovation competition organized by Ifremer. In partnership with this Institute, it will develop a new technology to produce relief maps of the seabed and carry out an inventory of biodiversity.

The characterization of the seabed that borders our coasts is an important issue for a better understanding of marine habitats and their biodiversity. Currently, the main technique consists of involving a diver, equipped with oxygen cylinders and a camera, who will film the bottom of the sea. This method has limitations, as it is difficult to observe large areas of depth and to repeat this operation at regular intervals. breaks. In the end, it doesn’t really meet the growing conservation needs of the ecosystem. Nice-based start-up DEESS envisioned a completely different solution: sending a swarm of underwater micro-drones to photograph the seafloor. It has just won the Octo’pousse innovation contest organized by Ifremer. The institute will thus provide human, financial and material resources for the development of this project.

“At the bottom of the sea there is little visibility and it is difficult to photograph at more than 5 meters, explains Yannick Penneçot, co-founder of the startup. Our idea is to involve micro-drones that will take pictures between 3 and 5 meters from the bottom. They will move side by side, about 4 meters apart, and move forward at the same time to cover large areas comprehensively. 🇧🇷 To position these machines underwater, drones will fly over the surface of the water and have the role of guiding them. To do this, they will be equipped with sonar and will emit acoustic waves that will be reflected in the underwater micro-drones. This way, you can make them move forward at the same speed and prevent them from moving to the right or left, with the risk of a collision. The micro-drones will be able to know how far from the seabed they are positioned, and will be able to automatically adjust to avoid terrain-related obstacles.

All the photographs taken by the underwater vehicles will then be combined to form a mosaic of sorts. Through photogrammetric processing, a 3D digital reconstruction technique, it will be possible to draw a relief map of the seabed. And to identify the living species present, artificial intelligence algorithms will be used. “There are already species recognition algorithms based on photos and videos, precise Yannick Pennett. We will develop them with the help of Ifremer and our goal is to automatically recognize all benthic organisms[1] : starfish, sea urchins, shells… to produce species and habitat density maps. For example, we will be able to identify Posidonia, they are large underwater seagrass beds, excellent markers of biodiversity and water quality. 🇧🇷

One hundred underwater drones to map 1 km² per hour

In the Ifremer contest and in partnership with it, the start-up has 18 months to prove the concept of this technology. His intention is to demonstrate the feasibility of this device with 4 to 6 underwater drones. They must be able to work independently, without being piloted by a human, and combine navigation with photogrammetry. Eventually, if this technology works, it could be deployed on a larger scale: “one hundred drones are imagined to be involved, spaced 4 meters apart and therefore with a range of 400 meters, and moving at a speed of 2.5 km per hour to map 1 km² in one hour”, detailed Yannick Pennett.

In the future, this new device could be used by biologists to collect more and more data on the seabed to carry out environmental impact studies. “Today, if you want to install wind turbines somewhere, existing technologies do not allow for exhaustive coverage, analyze Yannick Pennett. The data is therefore fragmented and, at a certain point, we cannot observe anything, while 30 meters further on, living beings are really present. With full photogrammetric coverage, biologists will have a comprehensive view of the seafloor and informed decisions can be made. Faced with an infrastructure installation, we will be able to know exactly its consequences on the ecosystem. 🇧🇷


[1] From the Greek “benthos” which means depth, bottom of the sea, but also lakes, rivers. Benthic species live in and around the substrate.

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