Finally, during the opening hours of the station, we had to be constantly vigilant about the flow of passengers that remains important, even late at night or early in the morning. Many curious people stopped to ask us what kind of machine it was and what it was designed for. But beyond the security of our equipment, we had to avoid to have people on the pictures and on the point clouds.

The other delicate aspect was not to get lost in the station as we progressed. Although we have plans and routes, it was not clear exactly where we were, especially in the levels. Indeed, the 2D representation of the station does not correspond to its 3D reality. To simplify the plans, certain levels have been merged together as part of the same level whereas in reality, there are real differences that do not appear so obvious on the plans. The point cloud of the whole station demonstrates this aspect.

Data assembly and use

The work of post-production and assembly of the data has thus made it possible to create a digital twin of the station accessible from a web browser (IndoorViewer) allowing to simply navigate inside of it like a Google Street View. We have integrated RATP’s plans to also allow 2D navigation and easier access to the areas of your choice. The main difficulty encountered was that explained above with the obligation to define levels to facilitate navigation whereas in reality, it is extremely complicated to assign them to a logic of clear levels.

The ability to create points of interest directly in the 3D model has made it possible to reference all the metro lines and corridors of the station. This nomenclature thus makes it possible to add a fourth way of navigating in the model:

  • in photos way Google Street View
  • in the point cloud with a 3D perception
  • in the 2D plane
  • via the nomenclature

Manage a building inventory

This first use case with the RATP was focused on the problem of finding and assessing water seepage in a metro station. The traditional method would have involved surveying the station using 2D plans and attaching thousands of photos to illustrate each of the infiltrations.

In two nights, with the technologies used, we mapped and photographed the 130,000 sq ft of the station and then made the data (photos and point clouds) easily accessible from a web browser. The real advantage of this method lies in the fact that the photos are put in perspective with respect to their location in the space, and that it is possible to move in the model thanks to the thousands of photos taken but also to adjust the angle of view since at each position in the model corresponds to a 360 ° panoramic photo high definition. Finally, the digital directory created for each corridor or eventually each infiltration allows to simply find the area in the IndoorViewer, to be able to view it on the 2D map, to access the HD photos and to view the area in 3D thanks to the point cloud.

This digitization will also enable other use cases for various departments of the RATP Group, for instance to follow up maintenance activity or to make a BIM model of the station.

«Feedback, Véronique Harroch, RATP Project Manager»

Our technical coordinator advised us to commission the company Levels 3D to scan the Republique station as part of its rehabilitation project. As a project manager, this tool allows me to have a 3D picture of the station from the beginning of the project. It has the advantage of being searchable anywhere, any time, by all project stakeholders.

Without moving, we can visualize in a very detailed way the corridors and the docks of the station for multiple uses:

  • consultation by the surveyors in charge of signage, by the project managers, or by the technical coordinators;
  • creation of geo-localized points of interest to integrate the results of diagnoses on seepage status and planned treatments.
  • We can also take action or share an image extracted from the tool.

The cost of this service is a little higher than a classic photo report, but it is largely offset by its benefits: time savings for project stakeholders, completeness and quality of the photographic content, sharing and communication of information.