Micro-drones are an engineering marvel: small, fast, and agile. But they’re not the strongest machines around and are not capable of exerting a lot of force. Until now. Scientists from Stanford University and EPFL in Switzerland have created a micro-drone with a built-in winch. It’s capable of lifting up to 40 times its own weight and performing simple mechanical tasks like opening a door.
The key to the design is the use of interchangeable adhesives on the drone’s base. Microspines useful for digging into rough materials or for grabbing onto glass. Both microspines and silicone ridges only cling to surfaces in one direction. This means they can be easily detached. With these in place, the micro-drones can pull well above their 100-gram weight, exerting 40 newtons of force, enough to lift four kilograms.
What can these machines really do? One of the things these robots can do is open doors. Although Estrada notes that making this work was quite difficult. They had to build a hook that fit the door handle. And lining up the drones correctly was no easy task. “It was challenging in that a number of things had to go right,” says Estrada.
Inspired By Nature
The design was inspired by nature, says Matthew Estrada, a Ph.D. candidate at Stanford and co-author on the paper. The team looked to small flying insects as the nearest equivalent to micro-drones. They studied how wasps particularly are able to move prey much heavier than themselves.
“Wasps quite often grab large prey and move it back to their den,” Estrada told The Verge. But, if they don’t have enough muscle power to fly with their cargo “they have to drag it along the ground, hooking on with their claws and moving it bit by bit.” These winch-equipped micro-drones — named FlyCroTugs — work exactly the same way.
“If you look at most small flying things, they’re interacting with their environments through the use of these mechanisms all the time. They’re perching, climbing, dragging things along,” says Estrada. Micro-drones are now learning the same skills.
But, this is just a proof of concept. The idea that we can create micro-drones that don’t just fly around but can also manipulate their surroundings is promising. Large number of cheap, disposable micro-drones could work together in the future to perform various tasks. Clearing rubble for larger robots in disaster scenarios for example.