Engineers at the University of California, Berkeley have created the world’s smallest flying robot that can be controlled without any wires.
This tiny insect-like machine is less than 1 centimeter wide and weighs only 21 milligrams—lighter than a grain of rice!
Inspired by the flight of bumblebees, this robot can hover in the air, change direction, and even hit small targets.
Just like a bee visiting flowers, it could one day help with tasks like artificial pollination or exploring hard-to-reach places.
“Bees are amazing at flying, hovering, and navigating their environment,” said Professor Liwei Lin, who led the research.
“Our robot can copy some of these skills and be wirelessly controlled to fly and land on targets, just like bees gathering nectar.”
The research team published their findings in the journal Science Advances.
One of the biggest challenges in building such a tiny flying robot is powering it. Normal batteries and control electronics are too heavy for something this small. To solve this, the engineers used a clever method—they power and control the robot using an external magnetic field.
The robot is shaped like a tiny propeller and has two small magnets inside. When it’s placed inside a changing magnetic field, the magnets push and pull, making the propeller spin. This creates enough lift to make the robot fly. By adjusting the strength of the magnetic field, researchers can control where the robot goes.
This mini flying robot is much smaller than any other wireless robot with similar flying abilities. The previous smallest model was 2.8 centimeters wide—almost three times bigger.
“These tiny robots could be used to inspect tight spaces, like the inside of small pipes,” said Fanping Sui, one of the lead researchers.
Right now, the robot can only fly in a controlled environment. It doesn’t have sensors to detect wind or obstacles, so if something changes suddenly, like a gust of wind, it might lose control. But the researchers hope to improve this soon by adding active controls to help the robot respond to its surroundings in real time.
The team also hopes to make the robot even smaller—less than 1 millimeter—so it could eventually be powered by weak magnetic fields, or even radio waves.
Besides flying robots, the Berkeley team is also working on other tiny machines, like a cockroach-inspired robot that can survive being stepped on and “swarm robots” that work together like ants. These future robots could even be used in medicine—swimming or crawling inside the human body to help with surgeries.
“We’re just starting to see what these tiny robots can do,” said graduate student Wei Yue.
