Future oriented: Battery-powered drones, popular with consumers, can typically fly for about 30 minutes before needing to be recharged. Solar power could extend that time considerably as long as sunlight is available, and researchers are also finding ways to make these devices extremely small and lightweight.
Researchers from Peking University have revealed A prototype of an ultra-small drone that can run on solar power indefinitely. While far from a full-fledged device, the micro-drone could represent a major leap forward in terms of efficiency and longevity.
The video above shows the drone, small enough to fit in the palm of a researcher’s hand, hovering in place continuously for more than an hour. The video ends before the device stops working, but the study published suggests It can maintain its flight as long as it receives sunlight.
For comparison, similarly sized drones like the DelFly Micro The drone needs to be recharged after about three minutes of flight. Larger drones like the best-selling DJI Mini 3 advertise a maximum flight time of about half an hour.
Solar-powered drones aren’t new, but researchers say they’ve built the smallest and lightest one yet. It’s just a few inches long and weighs just under five grams.
Other microdrones have struggled to use solar power, because solar panels collect less energy as they shrink. Other experiments have had limited success with wirelessly transmitted power, equivalent to artificial sunlight. Beijing researchers say they have built the first ultra-small drone capable of sustained flight using natural sunlight, as shown in the video demonstration.
The main advantage of the device is its electrostatic propulsion, which consumes less energy than the electromagnetic motors usually used by drones. Combined with a power converter at the bottom, an electrode blade arrangement in the center, and a helicopter-type rotor at the top, the drone operates on just over half a watt.
There is still room for improvement, however. The prototype lacks the control mechanisms needed for directed flight, as demonstrated in the demonstration of it taking off from the ground and hovering in a vertical cage. While a fully functional drone would likely weigh more, it would still have a huge endurance advantage over other microdrones.
The researchers admit that they could also improve efficiency and performance. Additionally, integrating batteries for nighttime operation could allow the drone to operate 24 hours a day.