The ultrafast transition from an underwater drone to the aerial vehicle in less than one second is based on a new propeller design – making this transition between the different mediums faster than most prior aerial-aquatic robots. Designed by a team of scientists from China, the United Kingdom and Switzerland, the versatile robot and its bio-inspired adhesive disc could be adapted for open-environment aerial and aquatic surveillance research.
Travelling with whales
It’s well known that untethered drones can help research expeditions and wildlife surveys in expansive or remote environments such as the open sea, but some constraints remain. For example, untethered drones are not the best choice to use during lengthier missions because they have no external power sources 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. The robot features a suction pad inspired by remora fish – a family of 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, even on moving objects.
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 Mirko Kovac, who heads both Empa’s Materials and Technology Center of Robotics and the Aerial Robotics Lab at Imperial College.
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.