A team of researchers has developed a new generation of tiny, agile drones that look, act and maneuver like actual insects allowing them to operate in cramped spaces and withstand collisions.
If you’ve ever swatted a mosquito away from your face, only to have it return again (and again and again), you know that insects can be remarkably acrobatic and resilient in flight. Those traits help them navigate the aerial world, with all of its wind gusts, obstacles, and general uncertainty. Such traits are also hard to build into flying robots, but MIT Team has built a system that approaches insects’ agility.
The team has developed insect-sized drones with unprecedented dexterity and resilience. The aerial robots are powered by a new class of soft actuator, which allows them to withstand the physical travails of real-world flight. The robots could one day aid humans by pollinating crops or performing machinery inspections in cramped spaces.
This research work appears in the journal IEEE Transactions on Robotics
Typically, drones require wide open spaces because they’re neither nimble enough to navigate confined spaces nor robust enough to withstand collisions in a crowd.
The challenge of building small aerial robots is immense. Pint-sized drones require a fundamentally different construction from larger ones. Large drones are usually powered by motors, but motors lose efficiency as we shrink them.
The principal alternative until now has been employing a small, rigid actuator built from piezoelectric ceramic materials. While piezoelectric ceramics allowed the first generation of tiny robots to take flight, they’re quite fragile.
This research team designed a more resilient tiny drone using soft actuators instead of hard, fragile ones. The soft actuators are made of thin rubber cylinders coated in carbon nanotubes. When voltage is applied to the carbon nanotubes, they produce an electrostatic force that squeezes and elongates the rubber cylinder. Repeated elongation and contraction causes the drone’s wings to beat — fast.
These actuators can flap nearly 500 times per second, giving the drone insect-like resilience.
We can hit it when it’s flying, and it can recover. It can also do aggressive maneuvers like somersaults in the air. And it weighs in at just 0.6 grams, approximately the mass of a large bumble bee. The drone looks a bit like a tiny cassette tape with wings, though the team is working on a new prototype shaped like a dragonfly.
These mini-aerialists could navigate complex machinery to ensure safety and functionality. Other potential applications include artificial pollination of crops or completing search-and-rescue missions following a disaster.
News source: MIT
