Project gallery (GCP & Lidar reference surfaces)

This gallery is not exhaustive. If you do not find specific examples corresponding to your particular needs, please contact us so we can find you a solution.

Reference surfaces for the production of flood risk prevention plans

In 2011 and 2012, the French National Geographic Institute assigned various photogrammetry firms to draw up DTM (Digital Terrain Model) using a LIDAR airborne technique along several rivers for the production of flood prevention risk plans.

Two of them subcontracted the required reference surface survey to us, totalling half of the plots.

Over the two-year period and, in reality, two short periods between 2011 and 2012, we collected 5275 points distributed over 93 sites.

Survey of 93 refernce surfaces for flood risk prevention plans
Détail d'une surface de référence pour PPRI

Pléiades satellite image calibration at 417 airports in 87 countries on 4 continents

The firm Astrium Geoinformation Services, now part of the Airbus Defence and Space group under the name Airbus DS Geo SA, launched a worldwide call to tender in 2012 (for performance in 2013) for the collection of ground control points intended for Pléïades satellite image calibration at 1000 airports throughout the world.

257 were assigned to us (i.e. over a quarter of the world market) and the survey was performed in conjunction with 5 regional partners (East Africa, West Africa, Mexico, Indian Peninsula, Portugal and the islands of Portugal).

We performed field surveys at 119 airports (Asia, French West Indies and Europe), as well as all calculations for all 257 airports over a 6-month period.

On July 2016, after some additional contracts, total number of airports surveyed was 417.

GCP for Pleiade images around airports

According to the terms of the contract, we share ownership of the collected GCPs (5 per airport) with Astrium and therefore have a right of resale. The coordinates of these points are delivered along with logsheet including sketches, a site map and photos.

The list of airports is available for download here: download (kmz file). The positions of the collected points and a copy of the ID sheet (with approximate coordinates) can be supplied on request.

Ground Control Points for the production of cadastral maps for 11 towns in Tchad

In 2013, the government of Tchad created a centralized office for securing cadastral, land and domain data, with the technical assistance of Obertur Group. Obertur took aerial photos of the 11 towns relevant to this operation (Abéché, Ati, Doba, Fada, Faya-Largeau, Kelo, Mongo, Moundou, N'Djaména, Pala and Sahr).

For the production of orthophoto maps, the firm in charge of filming and orthorectification asked us to collect ground control points (between 5 and 30 per town).

In view of the sensitive geopolitical situation in this area of the world, we asked a local team to perform the field work after training the operators and technicians in the use of Trimble GSP/GNSS receivers, which they already possessed. Aerial photos were available to us for point selection.

We accompanied them to Moundou and Ndjamena to put their control point survey training into practise. They then issued us with the observation data as the survey progressed, to enable us to calculate the points and create a layout for our customer.

Ground Control Points on 11 Chadian cities
Formation des opérateurs tchadiens au relevé de points de calage