Dart-firing drones to monitor jungle climate

Scientists create robotic aircraft to deploy sensors within tree canopies at hard-to-access locations

DRONES that shoot sensor arrows into trees have been developed by scientists at Imperial University to monitor jungles hard to reach on foot.

A team of roboticists developed the bespoke drones, equipped with sensitive navigation equipment and a robust design, to measure changing humidity and temperatures and provide an early warning for forest fires.

The aircraft are designed to be able to access tall canopies in tropical and mountainous forests, which are typically difficult to monitor.

Developed in partnership with Swiss scientists, the technology also reduces the risks to researchers who would otherwise have to place the sensors themselves.

The drones were tested at Imperial’s

Berkshire campus, Silwood Park, and at Swiss laboratories in Dübendorf.

Prof Mirko Kovac, director of the aerial robotics laboratory at Imperial College London, said his team was looking to partner with non-government organisations and companies that want to collect better data about the climate and environment in remote areas.

Drones have commonly been used to photograph and map areas of the world that are hard to reach, allowing for greater understanding of the scale and impact of natural disasters such as forest fires, but scientists have struggled to monitor the space beneath the treetops.

“The question of how to sense inside of the canopy, so in the dense vegetation around trees or in the forest itself, is very much unexplored,” Prof Kovac said. “This can give good validation of the data and models that predict the climate inside of the forest.”

Sensor placement can be adapted depending on the environment, which can range from dense jungle to airier treetops.

In the busy canopy, where foliage makes it difficult to get close enough to trees to place sensors manually, a pilot uses a camera lens to identify a target location and shoot the dart from up to three metres away.

Where a forest is clearer, the drones also have the ability to place sensors on trees, or deploy sensors while dangling below branches higher up, using a grapple and tensile cable.

This reduces the energy usage of the drone allowing it to collect data for longer periods.

Multiple arrows could create wireless sensor networks for scientific monitoring, and cameras can also be used to identify wildlife and track the movements and behaviour of animals. The Imperial lab also developed origami-inspired bumpers to protect the drones from collisions that would knock less specialised aircraft out of the air.

Prof Kovac and his co-creators, Dr Salua Hamaza and André Farhina, are now working on the drones’ autonomous abilities, hoping to enable the crafts to pilot themselves without human intervention.

The sensors could offer scientists a much-needed window into how the natural world is changing due to human activities.