US Army: laser to enable UAVs to fly indefinitely

The US military is developing a ground-based laser which can charge drones as they fly and potentially help them stay perpetually in flight, Feilidh Dwyer report in WeTalkUAV. According to New Scientist, Army engineers working for the Communications-Electronics Research, Development and Engineering Center in Maryland are developing a laser which could fire beams from distances of up to 1600 feet (487 meters) in order to charge photovoltaic cells aboard small drones.

US Army laser to enable UAVs to fly indefinitely
The photovoltaic cells convert the heat from the laser into electricity.  (Illustration: WeTalkUAV )

The photovoltaic cells convert the heat from the laser into electricity. A major challenge of this system is that lasers generate enormous amounts of heat which can cause damage to the drone’s materials. The Army is therefore working on making sure excess heat from the laser will dissipate and the photovoltaic cells are the only part of the drones that comes in contact with the laser.

The appeal of a drone that can stay in the air indefinitely is easy to see. Bringing drones back to base to refuel or recharge takes times away from their mission. The vast majority of drones can fly for less than an hour. Two proposed solutions to this problem are hydrogen fuel cells and lithium-metal batteries. Lasers could represent a new direction for this technology entirely. Whether this method of powering drones would be practical for anything other than military applications is not yet known. One assumes that the laser is fired at the drone intermittently to recharge the cells, rather than constantly.

According to Futurism, the Army are looking to have the system ready to power drones on the ground by 2019 and in the air in 2020. The next hurdle would be getting permission from regulators.