Drone System for Bathymetry with Echo Sounder

Bathymetry is the measurement of the depth of water in oceans, rivers, or lakes. The standard measurement tool for bathymetry is echo sounding, and the survey process involves the use of a ship, boat or unmanned surface vehicle (USV) as a platform for the sensor.

Sometimes, the use of a boat can be complicated, especially in the case of small or hard to reach rivers and lakes. The use of USV is not feasible in every situation either. Firstly, it is necessary to have a good point of entry to the water for deployment/recovery. Secondly, it may be impossible to use USV in shallow lakes with lots of seaweed. Last but not least, in many cases, USV should be big enough to resist the waves and a big car may be necessary to transport it.

An alternative is to fly a drone (UAV) to carry the echo sounder. A drone is compact and easy to transport and deploy. Drones also have a high precision of following planned survey lines and can be used in any place where there is at least a small area for take-off and landing near the surveyed water surface.

The system includes:

• A commercially available drone like DJI M350 RTK, DJI M300 RTK, M210 or M600 Pro (as well as drones based on the Pixhawk autopilot)

• Echo sounder sensor on a rope (cable)

• Radar altimeter to measure the precise altitude of the drone over the water surface

• On-board computer SkyHub to control the mission and store geotagged measurements

• UgCS Expert ground control software

SPH Engineering offers three standard options available with different echosounder sensors:

• EchoLogger ECT D052S dual-frequency

• EchoLogger ECT D24S dual-frequency

• EchoLogger ECT 400S single-frequency