Scientists from the Northwestern Polytechnic University (NPU) in China reported on the development and field testing of a laser-powered drone. Such a drone can conditionally stay in the air indefinitely, which opens up new perspectives for traffic control, agriculture, emergency services, the military and much more.

Today, lasers are more often seen as weapons, including remotely engaging drones. Chinese scientists went from the opposite - they proposed turning a laser beam into a power source for drones. A photodetector is installed on the device, which converts the laser light incident on it into electrical energy. It would seem that nothing complicated. But for this, it was necessary to create an intelligent visual tracking system for the drone in a wide range of weather conditions at any time of the day.

The drone tracking system basically uses the same power-transmitting laser beam. The beam also transmits drone control signals. “Highlights of the study are a 24/7 intelligent visual tracking system and autonomous energy replenishment for an ODD (optically guided drone) over a long distance,” the team wrote on the NPU’s official WeChat account.

Tests indoors and outdoors during the day and at night proved that the algorithm tolerated “flare” well, withstood the test at different distances, did not allow the drone to lose stability in different conditions, and always accurately positioned the device in the air. Unfortunately, the researchers did not name the distances at which laser energy transfer was tested. This was done for reasons of secrecy, since the technology is also being created for military purposes. But from the presentation it follows that a laser-powered drone can rise "to the height of a skyscraper."

Another challenge was the optimization of energy transfer by the laser beam. The beam is attenuated in the atmosphere and the stronger, the greater the turbulence of the air, not to mention the presence of precipitation, smoke, and other "impurities". An adaptive beamforming system came to the rescue. The laser beam, by the way, is automatically turned off in the event of an obstacle in its path. This does not allow anything to be set on fire and destroyed in its path, which is very, very correct.

In the future, the researchers expect that laser-powered drones will be used for logistics, traffic control, agriculture, patrolling, rescue and military operations, and in the future, the technology will reach the point where it will be possible to create aerial transport routes, stratospheric satellites and even hang an artificial moon.