Case study: dual frequency bathymetric survey

Dual frequency bathymetric survey of a gravel quarry


Hélicéo carries out a dual-frequency bathymetric survey on a gravel quarry.

Mission was carried out with:
-The aquatic drone FoxBathy
-The DroneBox RTK
-Dual frequency echo sounder

Mission data:

– Weather situation: sunny
– Outside temperature: 18°C
– Missions performed in automatic and manual mode
– Accuracy of mission georeferencing: 10cm
– Total area covered by the mission: 30 ha (74 acres)
– Spacing between the trajectories: 10m
– Measurement frequency: 2 Hz
– Mission speed: 1 m / s
– Mission duration: 6 hours

The specifications:

The echosounder:
– Dual frequency echo sounder
– Transmission frequency: 200 kHz and 30 kHz
– Beam width: 9 ° for 200kHz and 26 ° for 30 kHz
– Detection of depths from 0.4 m to 200 m
– Centimetric resolution

The positioning system:
The DroneBox RTK

Data processing:

Data production method:
Extraction of information from bi-frequency echosounders and triangulation interpolation

Data format:
Point cloud of the survey plot and interpolation of a 50 cm mesh in XYZ format

Data projection system:
RFG93 L93 (planimetry) – IGN69 (altimetry)


– Min / max depths observed at 200 kHz: 0,41 m / 50,53 m

– Min / max depths observed at 30 kHz: 0,43 m / 56,51 m

– Average altimetry of the water surface: 202,8 m

– Average water temperature: 15,88 ° C

Retail map (scale 1: 12000)

Enquête de profil de longueur

Length profile survey

Interpolated point clouds at 50 cm


Monitoring the Durian Tunggal Dam in Malaysia

Case study: Monitoring the Durian Tunggal Dam   Skyshine, the Malaysian distributor of Hélicéo, conducts a bathymetric survey of the Durian Tunggal Dam. It is one of the main sources of water supply for the inhabitants of the state of [...]