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$96 3D-printed rocket that recalculates its mid-air trajectory using a $5 sensor

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Re: $96 3D-printed rocket that recalculates its mid-air trajectory using a $5 sensor

#361

Post by torginus »

lukan wrote: post #148
torginus wrote: post #144

Earlier quoted context omitted.

Lasers imo don't really have IRL advantages over machine guns and rockets, and their line of sight nature is a huge limitation.

Laser: - are cheap to shoot - do not fall on someones head if they miss (unlike firing bullets and rockets at a drone that will come down again) - do hit the target immediately if aimed right Problems with lasers are, cooling, power consumption limiting mobile use - and indeed targeting and fog and clouds.

You need about 2 MJ (or 2000 Watt seconds) to boil away 1L of water. The Dragonfire ship class laser puts out 50 KW, so it would take 40 seconds to do that, assuming it can fire without pause, all of the enrgy makes it into the target, and none of it gets reflected.

This is a container sized system that needs to be mounted on a ship.

Meanwhile in Ukraine you have auto turrets made from anything ranging from heavy machineguns to old AA guns, with some added optics and/or radar, which are super cheap and you can carry them around in vans.

Re: $96 3D-printed rocket that recalculates its mid-air trajectory using a $5 sensor

#362

Post by srean »

NoMoreNicksLeft wrote: post #358
rexpop wrote: post #342

Earlier quoted context omitted.

Reasonable people know to take your flippant tone for the colorful warning of a rotten, toxic brain.

[flagged]

> White phosphorous is a way to light up the night sky during warfare

Lol No. Hilariously no. The thing to use to light up night sky is Magnesium (mostly, also aluminum. nowadays specialized resins). The primary use of WP is for smoke, but it is used illegally as an incendiary munition.

For someone who talks so much about WP I did not expect this level of ignorance. Empty vessels sounds much, I suppose.

Use of WP is banned * in warfare by international treaty, on the grounds of avoiding unnecessary cruelty and suffering. There are other banned weapons, for example, dumdum bullets. *There is a specific exception made for WP, which the Israeli army habitually and illegally abuses.

No other army is known to be a repeat offender with regards to WP. It's use in an area with civilian population is strictly prohibited. Cliffs are not.

Given the number of false equivalences you have been drawing you sound like a shill.

Re: $96 3D-printed rocket that recalculates its mid-air trajectory using a $5 sensor

#363

Post by vidarh »

philistine wrote: post #352
vidarh wrote: post #87

Earlier quoted context omitted.

They should be sweating, because if the other side can fire 100 rockets for $10k that are close enough to not immediately and obviously be off target, and you don't know whether a more expensive one with actual explosives is hiding within that barrage, you now have 100 targets to try to intercept, and suddenly your costs have gone up dramatically while the other sides costs has barely moved.

It is warfare, not mere product delivery. The second you fire one of these you reveal your position, making you a target for immediate reprisal. You don't win wars by losing very fine soldiers on homemade close enough shots.

So mount a battery on a truck, fire, move, fire again. Do that on a few hundred trucks, and drive around places without any real target and you have the other side burning through their arsenal real quick.

This isn't a rocket that is viable when you need to e.g. cross the Persian gulf. But it is a rocket that shows there are potentially viable decoys at a similar cost sufficient to spead fear in an enemy force if you can drive a bunch of trucks close enough to fire off dozens of them each, with the enemy knowing odds are you've hidden a handful of small warheads in there.

It'd be pointless for a conventional force that has the upper hand. It'd not be pointless for a weaker force or insurgency that needs massive asymmetry in cost to stand a chance.

EDIT: Heck, build tiny launch batteries in a crate, and drive around dropping launch batteries with a timer, and by the time the first rocket goes off you might've already dropped 10 of them and driven off. Now every car large enough to hold even a small box is a threat, and you have a real quagmire.

Re: $96 3D-printed rocket that recalculates its mid-air trajectory using a $5 sensor

#364

Post by srean »

inglor_cz wrote: post #337
srean wrote: post #245

Earlier quoted context omitted.

Strike a light in front of a parked but otherwise active fin guided heat-seeker and its freaky to watch it come alive like a lazy beagle eyeing a treat.

Is there a video of that on YT?

Got curious. It's not a lighter

https://youtube.com/shorts/6fYM4OlkIgk?si=NFMgNKGWz7rCJm2B

Re: $96 3D-printed rocket that recalculates its mid-air trajectory using a $5 sensor

#365

Post by vidarh »

dgroshev wrote: post #329
Animats wrote: post #324

Earlier quoted context omitted.

Shelf life doesn't matter if you are firing them as quickly as you can make them, especially if you actually can make them as quickly as you need them because they're so simple. Right. High-volume users can skip the thermal batteries with decades-long shelf life, and just spot-weld a few AAA batteries inside the weapon. Just stencil the thing "Best if used by DATE". Good for a year or two at least. Skip the anti-corr…

AAA batteries don't have the current. Li-Ion is too fussy and has a pretty high self-discharge. Ukraine can afford the cardboard boxes because they are fighting in their own country. The US has an ocean to cross. Ukraine can get away with short shelf life because they are at war right now . The US has to stockpile because the supply chain has to run at some capacity in peace time to be able to ramp up quickly when ne…

> The US has an ocean to cross.

But this is exactly the point: This approach allows for insurgents or parties subject to overwhelming but expensive force to strain the logistics and budgets of their opponent. This is something that would be far more costly for the US to counter.

Re: $96 3D-printed rocket that recalculates its mid-air trajectory using a $5 sensor

#367

Post by vidarh »

dgroshev wrote: post #317
tgsovlerkhgsel wrote: post #314

Earlier quoted context omitted.

> propulsion, warheads, arming and safety, QA, traceability, climate and shelf life stability. The further down the list you go, the more optional the requirements get in a sufficiently dire scenario. Shelf life doesn't matter if you are firing them as quickly as you can make them, especially if you actually can make them as quickly as you need them because they're so simple. QA and traceability may matter less if yo…

I don't understand your point. Sure, Ukraine can cut a few corners that western militaries are unwilling to cut. They still can't produce a domestic ballistic missile at scale, because it's genuinely hard, and simple terror weapons like Qassams are useless for militaries. "100 rockets for $10k" is off by orders of magnitude.

100 harmful rockets for $10k is off by orders of magnitude, but that was entirely not the point.

The point is that if you're in a asymmetric position where you can't do much damage directly, then whatever you can do to make the other side waste expensive resources while putting them on constant alert is a win.

You don't need a warhead, or a viable rocket, to do that. You need something that looks enough like a viable rocket to force a response, because the other side knows that x% are real.

If that thing is cheap enough for you to fire large numbers of them, you multiply the problem for your opponent. Cheap enough, and you have the potential to overwhelm the capacity of their countermeasures entirely, at which point you increase the chance that some of their real rockets will make it through.

Re: $96 3D-printed rocket that recalculates its mid-air trajectory using a $5 sensor

#368

Post by [deleted] »

dgroshev wrote: post #320
esseph wrote: post #309

Earlier quoted context omitted.

> Iran's neighbours would need to intercept only a handful of drones, which is hardly an insurmountable challenge. It's a big challenge when you run out of interceptors...

We're absolutely not running out of APKWS. They are manufactured by tens of thousands, and Hydra 70s are even more numerous.

[deleted]

Re: $96 3D-printed rocket that recalculates its mid-air trajectory using a $5 sensor

#369

Post by vidarh »

dgroshev wrote: post #240
vidarh wrote: post #140

Earlier quoted context omitted.

TFA is literally about a $96 rocket. > propulsion, warheads, arming and safety, QA, traceability, climate and shelf life stability. You're entirely missing the point. These do not need to be reliable for the scenario I hinted at. They also do not need to be armed. They need to be large enough that if one of them is a higher quality rocket (not part of the $10k) that contains actual explosives, you have serious destru…

> TFA is literally about a $96 rocket It's a firework-grade rocket with no payload that can't even ignite reliably. To imitate even a TBM or a MBRM, you need similar kinematics, even if you're running without a payload. Maybe your solid rocket motor would be a touch smaller because you're not delivering hundreds of kilograms of explosives, but it still has to be large because of the rocket equation. With a large moto…

> It's a firework-grade rocket with no payload that can't even ignite reliably.

Doesn't matter at that cost.

> To imitate even a TBM or a MBRM, you need similar kinematics, even if you're running without a payload.

That is relevant in a conflict like Iran at the moment, where the distance that needs to be covered is large. It's not relevant in e.g. an insurgency or the moment you put boots on the ground, where it only needs to look like something potentially explosive coming towards your truck or your helicopter or your people and you have 20 seconds to decide whether to waste munitions on it or not.

Re: $96 3D-printed rocket that recalculates its mid-air trajectory using a $5 sensor

#370

Post by dgroshev »

vidarh wrote: post #367
dgroshev wrote: post #317

Earlier quoted context omitted.

I don't understand your point. Sure, Ukraine can cut a few corners that western militaries are unwilling to cut. They still can't produce a domestic ballistic missile at scale, because it's genuinely hard, and simple terror weapons like Qassams are useless for militaries. "100 rockets for $10k" is off by orders of magnitude.

100 harmful rockets for $10k is off by orders of magnitude, but that was entirely not the point. The point is that if you're in a asymmetric position where you can't do much damage directly, then whatever you can do to make the other side waste expensive resources while putting them on constant alert is a win. You don't need a warhead, or a viable rocket, to do that. You need something that looks enough like a viable…

To "look enough" like a missile that can hit something a hundred kilometres away with enough precision to not be ignored you need a missile that can fly a hundred kilometres. This is not cheap.

Instead of repeating myself, I'll just link a reply, if you don't mind: https://news.ycombinator.com/item?id=47389309

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