Researchers have long envisioned deploying armies of tiny flying robots to tackle vital tasks. The versatile machines could be used as first responders to trace gas or pollutant seepage during natural disasters, to survey crops in large farms, to help astronauts on space missions, and even to assist bees with plant pollination. However, fitting the heavy electronics required to power and control the wings into the robot's tiny frame has been challenging. Now, there is hope, thanks to RoboBee X-Wing — the world's lightest aerial vehicle that can fly without being tethered to a power source.