Projects gallery (Business applications)

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.olution.


ILS installation at Merowe airport (Sudan)

The Merowe Airport (Sudan) is set on the banks of the Nile, just next to the dam of the same name, 300 km North of Khartoum and 400 km South of the Egyptian border.

The ILS (Instrument Landing System) was built by the firm I-Elec who entrusted us with its installation.

The various items installed were: a localizer on each runway (02 and 20), the measurement circle and array points associated with each localizer, two glides, theodolite platforms, a weather mast and all offsets.


Merowe airport (Sudan)
Staking out on Merowe airport (Sudan)

We have set up several tens of ILS's, VORs and aerial beacons in mainland France and its overseas territories.

Mode S multilateration system control at Roissy airport (France)

Sensis Corporation, configure this system, an antenna survey using WGS84 coordinates and a precision check (metric) of the determined positions was required.

The check was performed by fitting a vehicle with a transponder and RTK GPS to simulate aircraft routes on the runways, taxiways and parking areas. The aircraft maintain continuous radio links with the control tower (day and night according to the airport) throughout this route. The two surveys were then compared using analysis software.

An article describing this service was published in XYZ magazine (published by the "French Association of Topography").

Accuracy control of a Multilateration Mode S system in Roissy CDG
Accuracy control of a Multilateration Mode S system in Roissy CDG

We performed these operations at around 15 major international airports throughout Europe and Asia.


Installation of three Continuously Operating Reference Station (CORS) in Senegal

The farm we were assigned to survey covers tens of thousands of hectares. Its tractors are fitted with guide bars for operating in RTK mode. In view of the size of the farm, 3 stations were required to ensure the RTK signal, transmitted by radio, was received over the entire area. Their coordinates needed centimetre-level accuracy, as a tractor can work with 2 different stations on a single plot.

We determined the coordinates using GPS/GNSS observations recorded at the stations and matching observations performed using a Trimble R8 receiver on the geodetic control points of the new Senegalese Reference Network (RSS - Réseau de Référence Sénégalais).

Setting Up three GNSS stations (CORS) for a farm in Senegal
Geodetic vertice of the Senegalese Network (RRS)

Farm survey using GPS/GNSS (Normandy)

This is a stud farm in Normandy, near Deauville. The survey, carried out before the Teria Network, was performed using RTK with a local pivot. Georeferencing of this pivot using long-term post-processing observations from available permanent GNSS network stations.

Environment & Golf Courses

Piezometer survey on Beauce's Groundwater

A piezometer is a device for measuring fluid levels and their variation over time.

The hydrological area of Beauce's Groundwater spans 9000 sq. km between the Seine and Loire rivers. It is divided into two hydrographic districts, Loire-Bretagne and Seine-Normandie, and two regions, Centre and Île-de-France. We conducted a survey on approximately 500 piezometers spread over Beauce for the Agence de l'Eau Loire Bretagne, together with groundwater level measurements using a probe.

The map below, published by DREAL Centre, only shows piezometers monitored on a regular basis.

Nappe phréatique des calcaires de Beauce
Relevé piezzométrique

Golf course survey (I Rovari et Genève)

When required, a GPS/GNSS survey can be used for a few special points (tee-off, bunker entrance and exit, green entrance and exit, etc. or the entire layout).

The two examples shown below (I Roveri Golf Course in Italy (left) and Geneva Golf Club in Switzerland (right) illustrate this.propos.

Relevé des points sigificatifs (départs, bunkers, greens)
Relevé des surfaces (départs, fairways, bunkers, greens)

Linear networks

Traversing survey on the provisional layout of a VHV power line in Gabon

For this study on a VHV power line measuring several hundred kilometres, a LIDAR survey was conducted by the firm Geophenix (FIT group - France). Ground control points and reference surfaces had to be identified in order to calibrate the surveys, with pivots deployed during the flight.

We were in charge of organizing, managing and monitoring the teams from the Gabon National Cartographic Institute responsible for field work.

Control points had to be built in clearings (which can be hard to find in the equatorial forest). We also performed GPS/GNSS observations, conducted reference surface surveys and installed receivers during flights for calculating the aircraft's trajectory.

Due to the absence of a homogenous geodetic network over such a large area, we calculated the departure and arrival points of each traverse using the IGS permanent GNSS stations.

Construction d'une borne de canevas géodésique au Gabon
Tracé d'une ligne électrique THT au Gabon

Topography and GIS

Topographic surveys for the Maurecourt road diversion (France)

For this operation, led by the Cergy-Pontoise metropolitan area, we performed gridding of 3D altimetric points for the production of contour lines and the layouts (edges) of roads and ditches.

Relevé topographique pour la déviation de Maurecourt (95)

Point survey for the Bois de Vincennes zoo audio guides

Founded in 1934 by the National Natural History Museum, Parc Zoologique de Paris (Bois de Vincennes Zoo) closed its doors for full refurbishment on November 30th, 2008. It reopened to the public on April 12th, 2014 after 27 months of work and nearly 6 years' closure.

Visitors can now enjoy audio guides offering information on the various animal species and their environments at each enclosure.

For this project, we performed a GPS point survey, georeferenced on the zoo plan in order to superimpose the two data layers.

Zoo du bois de Vincennes (75)

Civil engineering, mines and quarries

Site traversing survey between Ndolé and Manioc (Gabon)

Measuring around 50 kilometres in linear distance, this site was covered with dense vegetation. To position the vertices, the French firm in charge of the work (Dragages et Travaux Publics, a subsidiary of the Bouygues Construction group) initially enlarged several of the existing platforms to provide adequate GPS space.

The survey used for the project feasibility study, performed by a local firm, had been carried out using the Gabon coordinate system (GTM32), which differs from the UTM32 system, to ensure the country is covered by a single projection zone.

We pinpointed a levelling error of around 70 cm between the start and end of the project on the initial survey (vertices). This is due to the fact that the geoid undulation variation was not taken into account as is frequently the case when GPS technology is used by poorly-trained operators.

Polygonale de chantier entre Ndolé et Manioc (Gabon)
Tracé de la route entre Ndolé et Manioc (Gabon)

Site traversing survey between Ngaoundéré and Meidougou (Cameroun)

These two villages are separated by around 175 km of track. The construction of a tarmacked road in place of the track was financed by the African Development Bank and Republic of Cameroun.

The site was divided into 2 plots of equivalent lengths. The southern section was performed by the French firm Dragages et Travaux Publics, a subsidiary of the Bouygues Construction group, and the northern section by the Portuguese firm Zagope, a subsidiary of the Brazilian group Andrade Gutierrez.

We were successively appointed by both firms to set up around a hundred control points comprising the main site traverse, i.e. one control point every 2 km approx.

Polygonale de chantier entre Ngaoundéré et Meidougou
Tracé de la route entre Ngaoundéré et Meidougou (Cameroun)