The designers of an innovative drone, that can travel through air and water, say the robotic technology was inspired by tropical suckerfish.

The ultrafast transition from underwater drone to aerial vehicle occurs in less than a second, and is based on a new propeller design where a suction disc hitchhikes on moving objects to save power and make the transition between the different mediums faster than most existing aerial-aquatic robots. The technology was inspired by remora, also known as suckerfish, a family of fish species known for their adhesive discs, which help them catch a ride on marine creatures including whales and sharks.

The remote-controlled robot’s disc can stick to wet and dry surfaces with different textures, and even onto moving objects. Designed by a team of scientists from Beihang University in China, Imperial College London and Swiss materials research and testing facility Empa, the device could be adapted for open-environment aerial and aquatic surveillance and research.

Untethered drones can help research expeditions and wildlife surveys in expansive or remote environments such as the open sea, but they are not the best choice to use during lengthier missions because they have no external power source to fall back on if their battery fails. To address this limitation, the scientists 3D-printed an aerial-aquatic untethered robot that reduces its power consumption through hitchhiking.

In tests, the robot hitched a ride on a swimming host vehicle to obtain seabed images of hermit crabs, scallops, and seaweed.

"Our study shows how we can take inspiration from the adhesion mechanism of the remora and combine it with aerial robotics systems to achieve novel mobility methods for robotics“, says Professor Mirko Kovac, who heads both Empa's Materials & Technology Center of Robotics in Switzerland and the Aerial Robotics Lab at Imperial College London.

During the process, the hitchhiking robot consumed almost 20-times less energy than it would have using self-propulsion. Through their outdoor experiments, the team could show that the robot can hitchhike, record video during air-water transitions, and perform cross-medium retrieval operations in both freshwater and saltwater environments.

The research was published in Science Robotics journal.