Inspection of an underwater dam

Mission’s context

Something you need to know about IVM Technologies is that our actions are fueled by our core mission: to make subsea inspections smarter, faster and more accessible through advanced photogrammetry. This guiding principle shapes every decision we make and it’s why we never stop innovating.

In 2023, this forward-thinking approach led to the development of the IVM SLAM, a Visual Simultaneous Localization and Mapping (VSLAM) system. Basically, this is a real-time subsea 3D modeling solution designed to complement our photogrammetry units. With IVM SLAM, we move one step closer to fulfilling our mission: reducing the cost and complexity of subsea inspections.

learn more about the IVM SLAM

IVM Solution

To test and fine-tune IVM SLAM’s performance, we conducted a series of trials in real conditions —one of the most revealing took place in the Port-Miou underground river. This unique site holds significant scientific interest due to its rare geological features. It also hosts an underwater dam built in the 1970s, offering an ideal setting for inspection. We conducted the survey with the Hydro 300, our robust photogrammetry unit designed for shallow water and with a maximum depth rating of 300 msw. Concerning the IVM SLAM, it is a topside computer designed as a true plug-and-play solution, it integrates effortlessly with all our photogrammetry units.

This trial had a two objectives:

Validate the final version of IVM SLAM, under real inspection conditions, with a full 3D reconstruction of both the dam and its surrounding rock formations.
Conduct the first photogrammetry survey of the site and generate an accurate 3D model.

To assess accuracy, we relied on existing data from a previous survey conducted by divers. Although no photogrammetry had ever been performed at this location, this site was well documented and we had access to photographs and reference maps. This material served as a valuable baseline to compare against our SLAM-based reconstruction and evaluate its precision.