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 Assistant Professor Kevin Yufeng Chen has built a system that approaches insects' agility. Chen, a member of the Department of Electrical Engineering and Computer Science and the Research Laboratory of Electronics, 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.
Kevin Chen, an assistant professor at the Massachusetts Institute of Technology, envisions a time when his insect-sized drone could be used as a search and rescue robot -- to find survivors in disaster debris that bigger drones couldn't reach. Kevin Chen, an assistant professor at the Massachusetts Institute of Technology, envisions a time when his insect-sized drone could be used as a search and rescue robot -- to find survivors in disaster debris that bigger drones couldn't reach. The reason it's so hard to kill a mosquito is that they move really well. Scientists are trying to build a robot with that kind of agility. And these tiny but mighty flying robots could be used in life-and-death situations, such as finding people in a collapsed building.
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. "If we look at most drones today, they're usually quite big," says Chen. "Most of their applications involve flying outdoors. The question is: Can you create insect-scale robots that can move around in very complex, cluttered spaces?" According to Chen, "The challenge of building small aerial robots is immense." Pint-sized drones require a fundamentally different construction from larger ones.
MIT researchers have developed a tiny drone with soft actuators that can flap nearly 500 times per second, allowing it to be more resilient to mid-flight bumps and nimble enough to fly like a bee. MIT Assistant Professor Kevin Yufeng Chen led the project to build an insect-like drone that uses soft actuators rather than hard, fragile actuators. "The soft actuators are made of thin rubber cylinders coated in carbon nanotubes," explains MIT. "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."