tl;dr: drones can be tethered by fiber optic cables. The cable provides jam-proof communication between the drone and the operator; and it also supplies power to the drone so it doesn’t need a massive battery pack and can stay airborne longer.
In the case of drones, the fiber optic cable provides a direct, stable, and high-capacity link for both power and data transmission. […] The fiber optic cable also supplies power to the drone, meaning the UAV doesn’t need a huge battery onboard.
Sadly, the article has been written by a non-competent person.
I can claim to be a competent person and explain a bit.
At a drone’s own voltage (4…8 lithium cells in series), powering an FPV attack drone requires 2 wires of 2,5 - 4,0 square millimeters of thickness. One meter of this pair of wires weighs about 50 grams. One kilometer would weigh 50 kilograms, but would exhibit a voltage drop proportional to length, so in reality, you’d need to increase the diameter several times.
If one was into physical experiments, using super high voltage and thinner wires, this could be brought down, but voltage converters on both ends would gain weight and insulation thickness would have to increase: as you raise voltage in an electrical cable (e.g. into kilovolts) current starts arcing across air gaps and breaking though insulation. That’s why high voltage power lines have long ceramic / glass insulators. :) So building a hypothetical “330 kilovolt drone” would be the last thing anyone would do. :)
Power Over Fiber “is a technology in which a fiber-optic cable carries optical power, which is used as an energy source rather than, or as well as, carrying data”.
Now I’d recommend looking up how much power can be transported by the very few implementations out there, and how much they cost.
Anything coming close to being able to power a drone would need way thicker fibers, increasing the drone weight. Any too big bend would set the fiber on fire. And it costs so much that building a slightly bigger drone with more batteries is cheaper.
Commercial systems generally deliver about a watt at 10-20 meters, which of course drops with distance and depends on fiber quality. It also requires a separate fiber(pair) from the data fiber.
The keyword is “optical power”: laser light. But a drone doesn’t need laser light to fly, it needs electrical power. Payload carrying drones need considerable amounts, 1 kilowatt might be typical. There is no readily available equipment to convert that amount of optical power into electrical power inside a drone, at an acceptable efficiency (solar panels have an efficiency of ~25%).
In addition, it helps to know: these drones use a single 25 micrometer single mode fiber (the power of the fiber transceivers is in milliwatts). It is hard to pack considerable power into that cross section, the optics are complicated (optics aside, a kilowatt class laser is very expensive). When you transmit laser power over fiber, you generally benefit from using a cable made of many fibers, or a considerably thicker multimode fiber.
Ukraine has had a lot of success using remotely operated suicide drones. They are cheap, built mostly from off the shelf hobbyist grade components, but with a few inexpensive upgrades the signal goes for miles. Strap a grenade on the bottom or any kind of bomb with an impact fuse and you have an excellent remote control weapon.
So of course the Russians start deploying radio jammers to block the drone signals.
The solution to this is fiber optics. The drone carries a giant spool of hair thin fiber optic cable which sends control commands from the operator and video back from the drone. Because it’s a cable, it’s immune to jamming.
The cable is insanely thin, usually in the tens of microns thickness. So they don’t bother recovering the cable, drone flies out spooling out cable behind it, hits its target and blows up, operator just detaches that fiber and pulls out another drone with another spool of cable to start again. This leaves tons of little fibers laying around on the countryside because every drone leaves one in its path.
That’s the point of this video. Most of those fibers have a dead Russian soldier at the end of them.
Wondering the same thing myself
This link explained a lot for me
https://defensefeeds.com/analysis/how-do-fiber-optic-drones-work/
tl;dr: drones can be tethered by fiber optic cables. The cable provides jam-proof communication between the drone and the operator; and it also supplies power to the drone so it doesn’t need a massive battery pack and can stay airborne longer.
Fiber optic cable can’t supply power.
They could if it was a copper wire, but then it’s even heavier.
According to the article:
There’s no way that’s correct though, with current technology
Maybe this is why we shouldn’t have AI write articles. Does the drone have a solar panel on the other end of the cable?
Sadly, the article has been written by a non-competent person.
I can claim to be a competent person and explain a bit.
At a drone’s own voltage (4…8 lithium cells in series), powering an FPV attack drone requires 2 wires of 2,5 - 4,0 square millimeters of thickness. One meter of this pair of wires weighs about 50 grams. One kilometer would weigh 50 kilograms, but would exhibit a voltage drop proportional to length, so in reality, you’d need to increase the diameter several times.
If one was into physical experiments, using super high voltage and thinner wires, this could be brought down, but voltage converters on both ends would gain weight and insulation thickness would have to increase: as you raise voltage in an electrical cable (e.g. into kilovolts) current starts arcing across air gaps and breaking though insulation. That’s why high voltage power lines have long ceramic / glass insulators. :) So building a hypothetical “330 kilovolt drone” would be the last thing anyone would do. :)
I have to imagine the article is just wrong about this part, but maybe there’s something I’m missing.
Power Over Fiber “is a technology in which a fiber-optic cable carries optical power, which is used as an energy source rather than, or as well as, carrying data”.
Now I’d recommend looking up how much power can be transported by the very few implementations out there, and how much they cost.
Anything coming close to being able to power a drone would need way thicker fibers, increasing the drone weight. Any too big bend would set the fiber on fire. And it costs so much that building a slightly bigger drone with more batteries is cheaper.
To save people the click:
Commercial systems generally deliver about a watt at 10-20 meters, which of course drops with distance and depends on fiber quality. It also requires a separate fiber(pair) from the data fiber.
A small DJI burns about 100 watts
Has it actually been deployed for aerial drones, or just theoretically?
See reference [1] if the article: https://optics.org/news/4/5/1
It seems to work at least for small surveillance drones.
The keyword is “optical power”: laser light. But a drone doesn’t need laser light to fly, it needs electrical power. Payload carrying drones need considerable amounts, 1 kilowatt might be typical. There is no readily available equipment to convert that amount of optical power into electrical power inside a drone, at an acceptable efficiency (solar panels have an efficiency of ~25%).
In addition, it helps to know: these drones use a single 25 micrometer single mode fiber (the power of the fiber transceivers is in milliwatts). It is hard to pack considerable power into that cross section, the optics are complicated (optics aside, a kilowatt class laser is very expensive). When you transmit laser power over fiber, you generally benefit from using a cable made of many fibers, or a considerably thicker multimode fiber.
Thank you, that was helpful.
Ukraine has had a lot of success using remotely operated suicide drones. They are cheap, built mostly from off the shelf hobbyist grade components, but with a few inexpensive upgrades the signal goes for miles. Strap a grenade on the bottom or any kind of bomb with an impact fuse and you have an excellent remote control weapon.
So of course the Russians start deploying radio jammers to block the drone signals.
The solution to this is fiber optics. The drone carries a giant spool of hair thin fiber optic cable which sends control commands from the operator and video back from the drone. Because it’s a cable, it’s immune to jamming.
The cable is insanely thin, usually in the tens of microns thickness. So they don’t bother recovering the cable, drone flies out spooling out cable behind it, hits its target and blows up, operator just detaches that fiber and pulls out another drone with another spool of cable to start again. This leaves tons of little fibers laying around on the countryside because every drone leaves one in its path.
That’s the point of this video. Most of those fibers have a dead Russian soldier at the end of them.
Its very “the fates”. Literally clipping threads.