It's not even electrical output. They mount harness to the drone carrying payload with a 9V battery (or whatever) with a light sensitive resistor positioned over the auxiliary light. When the light turns on the payload is released with a motor/solenoid/something running from that battery on the harness and it doesn't require any modification to the drone itself.

[–] CanadaPlus@lemmy.sdf.org 6 points 2 weeks ago (1 children)

Interesting. I wonder why that's easier than just pulling out the LED?

[–] IsoKiero@sopuli.xyz 9 points 2 weeks ago* (last edited 2 weeks ago) (1 children)

It's and SMD led on a main board of the drone (at least on DJI ones) and the whole board is quite a complex computer with a ton of RF tech, power limitations and whatever is included to make those things both safe and fun for your average consumer. For a skilled operator it's not a problem to pull out the led and wire it to a transistor, but you need to pull the whole drone apart, somewhat sophisticated tools to solder wires to the led contact points, reassemble the whole thing excactly as it were and then connect that to the external harness.

Or, you can just bend the frame out of chicken wire, twist wires together and secure them with a tape or hot glue, zip-tie that to a drone and you're good to go. I think in Ukraine they use a ton of 3d-printed stuff which makes it more reliable and even easier to assemble. That way you don't risk breaking the drone and you can prefab pretty much the whole thing and just send them out to the field where practically anyone can assemble it even on standing in a mud puddle and have successful results within minutes from pulling a new drone out of a box.

[–] CanadaPlus@lemmy.sdf.org 3 points 2 weeks ago* (last edited 2 weeks ago)

I guess that makes sense. Easier to just assemble than disassemble+assemble. It might cost slightly more in materials and preform slightly worse, but they're primarily limited by people and time, not aid dollars to import electronics.

[–] Hubi@feddit.org 3 points 2 weeks ago

Wow, I had no idea. I always thought it's just rewired to the harness. Thanks for the information.

[–] potentiallynotfelix@lemmy.fish 2 points 2 weeks ago

Pretty genius, as a drone builder myself I appreciate lots of the drones being built during this war. Just unfortunate they have to be used for this purpose.

[–] Tar_alcaran@sh.itjust.works 10 points 2 weeks ago

Ahhh, makes sense, but I never knew that.

[–] Luccus@feddit.org 13 points 2 weeks ago

Who downvoted that?

You have to watch pretty fucked up footage to get this joke. Imo it's a really reasonable question.

[–] ladicius@lemmy.world 6 points 2 weeks ago (1 children)

I thought the most iconic sign in the display was "battery low".

[–] tal 3 points 2 weeks ago* (last edited 2 weeks ago) (1 children)

I have to say that one minor but unfortunate aspect of this conflict is that we're not doing a great job of recycling an awful lot of lithium batteries.

EDIT: One thing I have been wondering about is the practicality of an FPV carrier -- like, a reusable winged drone, maybe with a deployable chute for landing or something, or a larger quadcopter -- that can launch an FPV quadcopter to do the actual hit. That provides range, possibly slashes time-to-target, and lets more parts be reused. The less that has to go on the vehicle that actually explodes, the better.

[–] IsoKiero@sopuli.xyz 11 points 2 weeks ago (1 children)

While you are of course correct on this, the amount of waste and environmental damage Russia is causing by blowing up dams and pretty much leaving a trail of garbage where ever they go combined with the pollution and wasted resources on burning fuel (both in engines and otherwise), destroying buildings and everything else going on, the couple truckloads of small LiFePo batteries on drones aren't even a rounding error in the equation.

I'm not an expert on what residual materials come from burning batteries, but I'm willing to bet that plastic from pretty much everything on the field has a bigger environmental affect, even the drones themselves are mostly just a plastic shell with very little of anything else in them.

[–] tal 4 points 2 weeks ago* (last edited 2 weeks ago) (1 children)

Oh, yeah, not saying that it's a contest or that Ukraine (or Russia) should stop using FPVs or loitering drones. I mean, if there isn't a better alternative, then there isn't a better alternative. Just that it's an unfortunate aspect of having lots of electrically-powered things that both need lightweight, high-density batteries and need to explode, when we're lithium-constrained.

Wasn't even principally thinking about the pollution aspect, just the "that's more lithium that probably isn't going to be recoverable" aspect.

[–] IsoKiero@sopuli.xyz 5 points 2 weeks ago* (last edited 2 weeks ago)

Amount of lithium in a single drone battery is minuscle. Quickly googled answer says that there's about 7% from weight lithium in a battery, so your average drone cell might have something like 10-20 grams of lithium in it (altough that 7% is for Li-Ion and drones tend to use LiFePo, so that number might be wrong). In a single electric car there's tens of kilograms of lithium inside. So a single car fire anywhere in the world "wastes" more lithium than hundreds and hundreds of drones in Ukraine.

Sure, it would be nice to recover that small amount too, but in practise we need a better material than lithium for our batteries. Also there's things like single-use vape-pens which use perfectly fine li-ion cell but it was manufactured without any means to charge it, a handful of those discarded on a nearest trash can (or more likely to the street next to it) is comparable to a single drone battery and people throw those away without concern every day.