Laser beams replace landing pads for drone recharging
Imagine a fleet of unmanned aerial vehicles that never need to touch the ground to swap batteries. A research team from the Civil Aviation University of China has turned that vision into a laboratory reality by beaming a focused laser onto a lightweight receiver mounted on a drone’s wing. The concept mirrors the wireless charging we use for smartphones, but it operates at a scale and intensity that can sustain a flying platform for extended missions.
How the perovskite‑laser‑thermo‑electric device works
The heart of the system is a perovskite‑laser‑thermo‑electric (PLC‑TE) module. Unlike conventional solar cells that harvest sunlight, this device is tuned to absorb a specific green‑laser wavelength. The perovskite layer converts the incoming photons directly into electrical current, while an adjoining thermoelectric layer captures the heat that would otherwise be wasted. The larger the temperature gradient between the hot side (exposed to the laser) and the cold side (cooled by airflow), the more voltage the thermoelectric section can generate.
Overcoming the heat challenge with nanocrystals
High‑power lasers inevitably raise the temperature of the receiver. Initial tests recorded surface temperatures of 80‑90 °C, threatening both efficiency and component longevity. To mitigate this, the researchers embedded a lattice of nanocrystals that act as a thermal barrier. These crystals conduct heat poorly, slowing its flow toward the sensitive electronics and allowing the device to maintain a stable conversion rate even under prolonged illumination.
Performance figures and proof‑of‑concept flight
When illuminated by a green laser, the prototype achieved a conversion efficiency of 38.49 %—one of the highest reported for laser‑driven power harvesters in comparable conditions. In a bench‑top demonstration, the module was installed under the wing of a stationary drone model with custom‑cut air channels. As soon as the laser was switched on, the propeller sprang to life, and the induced airflow further cooled the cold side of the thermoelectric layer, boosting output.
Next steps toward real‑world operation
Although the stationary test proved the concept, the team acknowledges that an actual flight test is still pending. The upcoming experiment will mount the PLC‑TE unit on a lightweight UAV and evaluate its reliability in open‑air conditions, where factors such as wind, vibration, and varying laser alignment come into play. Success would mark a pivotal shift in how drones are powered, potentially extending mission durations for tasks ranging from forest monitoring to disaster response and last‑mile delivery.
Source: https://scientias.nl/vliegende-drones-opladen-met-een-laserstraal-is-het-accuprobleem-opgelost/