Apparently this was too credible....
I posted this OC 8 months ago, today i see this in my YT feed:
https://www.youtube.com/watch?v=m2-p2srIRLI (Ukraine Counters Fibre-Optic Drones with Lasers That Fry the Cables)
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Comments36View original on sh.itjust.works
Well done.
I didn't think fibre optic cable worked like that.
On the case of the real drone, the laser is destroying the cable.
On the OP's case, yes a laser can interrupt the communication. But the drone needs to keep sending it, or the drone will just continue after it's gone. On the other hand, you need less power.
unless it injects a detonation command
If you can inject commands into a communication line, somebody was really stupid while designing it.
Well those fiber optic line end points are not exactly encrypted, they use off the shelf components like HDMI over Fiber adapters, and serial over fiber for control link. In rare cases they could maybe use a actual IP connection over fiber but i doubt that since, it would add overhead, latency and make the hardware setup a lot more complex and expensive (if would be able to encrypt tho).
Wouldn't any civilian endpoint they're buying be designed to use IP?
no, because often its not "internet/network over fiber" stuff but HDMI over fiber no ip there. HDMI cables have very limited lenght due to high frequency beeing used in em, so if you have a media production company and a few spread out cameras HDMI over fiber is kinda common
Huh, TIL!
Which happens, but then a different idiot tends to fix it. See what happened with the Starlink-controlled drones.
The fibre that's carried by combat drones is uncoated, so with the right angle it's possible to inject another signal.
We still don't know the full story, it was probably a drone flying rounds trying to detect fiber optic and something else cut the cable, there's no way you're powering a 5kW laser off a quad
edit: even if it's tethered, which isn't a real thing yet
does it destroy the actual glass cable, or does it get inside and travel along the optic path and burn out the transceiver? burning the glass to breaking point seems like it would take a heck of a lot of energy, so i assumed it was attacking the light sensors at each end of the line, but people keep saying it's actually breaking the glass.
thats a very good question, let me suggest 2 more options:
It injects laser into the fiber, coded identical to the command that would be used to detonate the drone.
It dosent need to fully burn thru the whole fiber, just melt it a tiny bit to increase fiber losses to a point where the connection fails
The actual power to cut the fibre would be a lot lower than you think.
Assuming a 100um thick fibre, ant heating a 5cm length, it's a volume mass of around 10e-7kg. That would take about 1.5J (not kJ) to melt.
The catch is whether you can find an efficient enough laser, that outputs at a frequency the glass is opaque to.
And it needs to be accurate enough to focus on an unsecured clear cable in uncontrollable weather conditions for a long enough time. You'd need a lot more power than what the basic physics in an ideal scenario would suggest.
You would still have that issue when trying to inject commands into the fibre.
You also don't need to target the fibre directly. Just sweep the area with enough focused power to burn one out.
Defocusing would be the biggest range limiter. You could likely get 100m+ with the right setup, and keep it drone mountable. Not ideal, but potentially viable.
How about a mirror on a drone?
Now try to fit enough batteries to power that laser on a drone lol (spoiler: you can't)
ok so the giant battery is in the tank, guess how big a cable would have to be? You're not putting that on a quad
edit: it's also impractical as hell to tether drones when most roads get netting installed over them, just saying
edit2: why not just put the laser on the tank? fry the drones around you directly instead of hoping you cut the comms in the fiber optic lines
not very
I can show you a chunky 500W cable for a pc power supply, would be just as relevant. Look up cables of actual laser power supplies, they're big and relatively dense, and we're talking about tethering a quad, it's not gonna fly well with that dangling.
This man has never heard of ohm’s law
Not a man but I take your point, consider that this drone and the cable is gonna get peppered like crazy. Plus you don't want it tangling up
Apologies, I had meant “man” as person but I recognize that usage is dated. No gender assumption was intended.
This ohm's law?
the tank has a giant gas turbine why do you need a battery
Find me a tank with a 5kW turbine
edit: i misread the units yall don't stone me to death
The battery isn’t the issue they were talking about. They meant “so instead of batteries on the quad you’re powering it from the tank.”
The gas turbine in an Abrams produces 1100 kW
https://en.wikipedia.org/wiki/Avco-Lycoming_AGT1500
If you mean a dedicated turbine producing 5kW of electricity then it already has an accessory gearbox drawing up to 75kW out of the 1100 for peripherals. I doubt they're currently generating (pun intended) huge amounts of electricity, but the drive is there for exactly this sort of purpose.
A 5kW alternator seems to be about $700 on ebay
https://www.ebay.com/itm/146849456677
If a reasonably skilled engineer cant fit that there's something wrong
My bad, i misread the units
It wouldn’t have to run at full power all the time, just when actively defending against a drone. There are lots of other harder to solve issues.
Ok and? Still needs batteries and cables to withstand peak power, still needs to be tethered somehow, still needs another crew member constantly flying it. Not to mention being this close to combat and to the ground, you better have some insanely good lens protectors or that laser is gonna be out of commission after any shrapnel lodges itself in.
Completely made up idea to counter this made up idea, but if you're putting it on armor - a 12 gauge turret sounds so much easier. Doesn't need a shitload of power, can put it onto a generic stand/turret base, targeting is easier and you're guaranteed to ruin the enemy drone's life
The laser could be on the tank with a mirror on the drone
Archimedes would love it.
Now we're cooking with gas