Sensor-packed underwater drone to shed light on marine life

By developing state-of-the-art optical technologies, DTU researchers will document marine biodiversity in much more detail than divers and satellite images do today.

Christian Pedersen står bøjet ind over et laserapparat og skruer på en knap, mens Joaquim Santos ser på.
 Christian Pedersen and his colleague, PhD student Joaquim Santos, have developed a unique laser system that will measure plankton in the water column. Photo: Thomas Steen Sørensen.

Unique laser system spots plankton

Above the seabed, life in the ocean is very layered. Many species of plankton only live at a specific depth, temperature, salinity, and level of light. Until now, the biodiversity of the open sea has been analysed by sending a sampler down to a certain depth and then retracting it and analysing the species in the sample, but this is a slow and strenuous method. Ocean Eye therefore aims to develop a special lidar, which is the type of laser system used in self-driving cars to measure distance. The researchers’ laser system will be able to focus on a specific depth and detect what kinds of microalgae and zooplankton (such as krill and copepods) live there. Initially, the laser system will be designed for coastal waters with depths of up to five metres, but it will also be able to operate at deeper levels.

“No one has ever created a lidar system that can detect marine life in this way before,” says Christian Pedersen.

Ocean Eye’s various sensors will be collecting so much data that it will be impossible to analyse it all manually. The team is therefore also working on developing an artificial intelligence that will chew through the data and conclude which species are hiding in the recordings.

“The three technologies complement each other, so when you take all the data and get an AI to analyse it, it can give a pretty accurate answer to whether what’s in the picture is a clam or red algae,” says Christian Pedersen.

Technology is the solution

The Ocean Eye prototype may still look like a DIY project, but the goal is to eventually install the sensors on an underwater drone that can sail around and measure biodiversity and its development over time, including in deeper regions. It will be a useful tool for marine biologists as well as authorities and decision-makers and will be able to document whether, e.g., marine restoration projects are working as intended.

“When we restore stone reefs, we want to understand what’s happening. Does one species take over everything because it’s quick as a flash, or what’s going on?” says Christian Pedersen.

The better we get at measuring marine life, the better we will understand what it will take to improve the marine environment.

“It speaks to all the major issues of how to improve the quality of the marine environment in Danish waters. But our project differs from other initiatives in that we bring technology into play as part of the solution,” says Christian Pedersen.


    • The project runs from 2023 to 2026.
    •  Has received DKK 6 million in funding from Villum Fonden.
    • It is an interdisciplinary collaboration project with researchers from the Department of Ecoscience at Aarhus University, which will test whether Ocean Eye’s measurements match the researchers’ physical observations, among other things.
    • The project was initiated by Christian Pedersen and Paul Michael Petersen from DTU Electro and Hans Jakobsen from Aarhus University.


The focus on biodiversity has increased sharply. Plant and animal species are threatened with extinction and many researchers describe the biodiversity crisis as the worst crisis facing humanity.

Biodiversity includes all life on the planet - in water and on land. This means animals, plants, fungi, bacteria and the ecosystems where plants and animals live, e.g. a forest or a lake.

At DTU, we work particularly with biodiversity in water.

Read more in our special topic about biodiversity.


Christian Pedersen

Christian Pedersen Group Leader, Professor Department of Electrical and Photonics Engineering Phone: +45 46774508