This laser-powered drone concept could fly “indefinitely.”

In recent years, individuals have been able to purchase increasingly sophisticated drones long reserved for wealthy professionals. But these machines still suffer from a universal limitation: autonomy, which remains limited due to the weight of the batteries. A team of Chinese researchers wants to change that. In a case uncovered by the South China Morning Post, its members presented a concept that could allow drones to fly ” indefinitely “.

To achieve this, Li Xuelong and his colleagues at Northwest Polytechnic University (NPU) relied on laser-based technology. It is a little surprising to know that these beams are mostly used to destroy unwanted quadcopters. In this particular case, the researchers want to use it to directly power a drone during full flight.

For this, the machine is equipped with a photoelectric conversion module. A component that converts energy carried by an electromagnetic wave, such as laser light, into electrical energy that can be used directly by a device. In theory, the latter could fly, at least indefinitely as long as the laser beam is maintained.

This is a concept that has already been explored in various contexts, particularly in the military sector. This Popular Mechanics article also describes a comparable system developed by the US Army. But so far, no one has been able to bring this technology to maturity.

Light-based umbilical cord

This is mainly due to two main limitations. The first is traceability. In fact, to power a drone, a laser must be permanently pointed at the conversion cell. And that’s easier said than done, because systems like these can easily go off the rails as soon as they encounter an unknown situation.

To overcome this obstacle, Chinese researchers have written a predictive algorithm that continuously tries to predict the drone’s next move. Although not explicitly stated, the wording suggests that it may be an AI-based system.

It seems to work very well, even in less-than-ideal conditions. The authors explain that it “ good tolerance at different light levels in any environment.

From there, the researchers were able to tackle a second, more difficult problem: energy transfer. Because even if the laser beam actually transmits a certain energy, the performance is not perfect. Not all of the energy supplied to the device is completely transferred to the beam. When the latter passes through a medium, part of the laser’s energy will be lost due to the phenomenon of diffraction. This is called a mitigationand this means that the energy will be less at the end of the beam than at the beginning.

A working proof of concept

In order to provide enough power to the drone, the researchers had to reduce this attenuation as much as possible. That’s why they developed a solution that allows them to adjust the shape and power of the beam in real time. This reduces the negative effect of atmospheric turbulence on the beam. And in addition, to improve energy transfer.

They also added a security system. If another object, such as a bird, passes between the drone and the laser source, the intensity will be adjusted immediately to avoid damaging it.

According to the South China Morning Post, these two elements have been integrated into the prototype. The latter managed to stay in the air for a long time. The authors believe that this proof of concept “ demonstrating potentially unlimited range for optically powered drones (or ODD, for optically guided drones).

Unfortunately, it remains several dimensions unknown. For example, the authors did not show how long the car could stay in the air. And above all, they remained very tight-lipped about the specifics of the conversion cell. We don’t know how long it can run or what its performance is. It is not surprising to know that these are technologies that can be used in a military context.

Military, industrial and civilian interest

Especially in this field, the reality of flying drones permanently would be very interesting indeed. This is especially true for monitoring. The authors explain that this system can also work wonders during relief operations. ” Continuous flight will save valuable time on very long missions, such as searching for stranded tourists. “, explain the authors of the work.

They also suggest that these SDGs could play a defining role in tomorrow’s logistics. This applies to both industry and communities. ” Optical drones could have a huge impact on traffic control, security patrols, contactless logistics… “, list researchers. We can also imagine drone relay would allowthus transferring energy over long distances, and wireless.

They also discussed the future of this technology in the field of transportation. ” Large drones can be transformed into real air buses to create a three-dimensional transportation network “, they point out. They go even further. According to them, this technology even “ low altitude satellite “or” artificial moon “. But before you get there, you’ll probably have to make a lot of progress in terms of performance.

In the meantime, it will be interesting to see in what contexts this technology can be useful as it is. Unfortunately, it is impossible to suggest this level of potential without knowing the conversion yield. The weaker it is, the more the SDGs will be reserved for rich and powerful institutions, especially on the military side. Even if this technology eventually takes off, it will likely take several years for consumer applications to appear.