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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

#321

Post by Animats »

ralferoo wrote: post #238

I remember an anecdote our robotics lecturer told our university class in 1995, which was about how in the west we try to make expensive things that are the absolute best of technology and how the other side didn't have that luxury and relied on ingenuity. He described a cold war Russian missile they had somehow obtained and were tasked with trying to reverse engineer. Ostensibly, it was thought to be a heat seeking…

That's roughly how the original Sidewinder worked. The original concept was to reduce near-misses. If the pilot could get on the target's tail and aim at the engines, it usually got a hit. That was the same task as getting into firing position for guns. Hit rate about 8% in combat.

Later versions allowed launches from longer ranges and from off-angles.

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

#322

Post by dgroshev »

Mars008 wrote: post #312
dgroshev wrote: post #230

Earlier quoted context omitted.

Ukraine does bother with all of that when they can afford it. I'd even say that FPV drones are the main exception, and only because Ukraine was so pressed for immediate results and had stockpiles to repurpose. There are only so many old RPG warheads you can reuse with a detonator made of live wires, and maiming your own launch crews because someone made a tiny wrong movement arming their thirtieth drone of the day un…

> Hezbollah is a terrorist organisation That depends from which side you are looking. From the other side they are patriots and defending their people and land, sacrificing their lives. Looks like in NATO you haven't seen that. The same in Vietnam, Iraq,.. there is a long list of 'terrorists' of this sort. Almost like 'suffering minorities'.

It's an objective statement of their tactics, not something relative.

Modern precision guided weaponry is meant to selectively destroy military targets. WW2 style strategic bombing was targeting civilian populations mostly trying to disrupt industrial production in support of military action. Randomly firing a few unguided rockets into civilian population centres can't possibly achieve either. The only goal is to provoke terror in the civilian population, therefore it's a terrorist organisation.

You can see similar tactics in the "human safari" the Russians are running in several Ukrainian population centres.

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

#323

Post by projektfu »

srean wrote: post #300
Mars008 wrote: post #296

Earlier quoted context omitted.

Well, there are cheap portable ultrasound scanners and endoscopes.

True. I was talking about those that are meant for hospitals. Was peripherally involved with a fledgling startup that was developing something cheap. Hospitals straightaway said noway.

They would be desirable in places with poor advanced imaging penetration like Brazil. Usually only the largest city in a state has this sort of imaging.

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

#324

Post by Animats »

tgsovlerkhgsel wrote: post #314
dgroshev wrote: post #115

Earlier quoted context omitted.

100 rockets for $10k is not happening. The price floor is not dictated by the electronics (which did get cheaper), it's dictated by the rest of the system: propulsion, warheads, arming and safety, QA, traceability, climate and shelf life stability. Take a look at Raytheon's manufacturing line: https://www.youtube.com/watch?v=kCCkVAHSzrc That's what it takes to have missiles that are nearly guaranteed to perform to sp…

> 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…

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-corrosion stuff and ship it in consumer-grade shrink wrap. Ukraine ships drones to the field in lightweight cardboard boxes, not rugged weapons containers.

Many US weapons are really old designs. The Patriot went into production in 1980. The Stinger went into service in 1981. There's been progress since then. Consumer-grade parts can do most of what's needed.

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

#325

Post by edmundsauto »

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.

I think the point is to look at the US requirements compared to the cost and explore ways that a country could gain strategic advantages by building objectively worse products. (But cheaper/faster, gaining an asymmetric advantage in the offense/defense scaling)

I used to think the US dollars were well spent, because we felt it was morally important to deliver precision strikes which had higher cost requirements. Recent evidence demonstrates that is insufficient when the wetware making the targeting decisions is faulty.

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

#326

Post by srean »

blincoln wrote: post #260
oofbey wrote: post #188

Earlier quoted context omitted.

This design is pretty clearly optimized for weaponry. Eg the foldable fins - necessary if you want to keep a magazine of these things stored compactly before firing. Totally unnecessary for funsies. What nonviolent application are you imagining for a gps-guided rocket that is launched by pulling a gun trigger on a hand held mount?

> What nonviolent application are you imagining for a gps-guided rocket that is launched by pulling a gun trigger on a hand held mount? A launcher for a climbing rope or grappling hook. Have you ever tried getting a rope up over a branch on a very tall tree? Not joking - I considered it as a hobby project years ago until I discovered how hard it would be to do legally.

Hatari

https://m.youtube.com/watch?v=5LqMAygTHEQ&t=120s

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

#327

Post by sofixa »

kdheiwns wrote: post #263
dgroshev wrote: post #115

Earlier quoted context omitted.

100 rockets for $10k is not happening. The price floor is not dictated by the electronics (which did get cheaper), it's dictated by the rest of the system: propulsion, warheads, arming and safety, QA, traceability, climate and shelf life stability. Take a look at Raytheon's manufacturing line: https://www.youtube.com/watch?v=kCCkVAHSzrc That's what it takes to have missiles that are nearly guaranteed to perform to sp…

If you think shelf life, QA, safety, blah blah blah matters when a rocket is 100 bucks, I have just three words: you will lose. The Ukraine war is being fought with a bunch of cheap toy style drones dropping grenades everywhere. The US got their bases blown to pieces across the Middle East by cheap drones that gently float through the air like a paper airplane in comparison to absolutely any missile. And let's not fo…

> The Ukraine war is being fought with a bunch of cheap toy style drones dropping grenades everywhere

This hasn't been true for 3-4 years now, most of the combat drones being used now are purpose built kamikaze drones. Notably the Russians are using Iranian designed Shahed 136s, while the Ukranians have the similar Liutyi. Among many, many, many other models in various roles.

> And let's not forget. The US had napalm, helicopters, bombers, incredible logistics, cutting edge equipment of all sorts. Vietnam had a bunch of sticks in a hole covered in poop. Those sticks sent Americans crying home and we still get movies and games with them crying about how bad it was.

While the Americans absolutely lost in Vietnam really bad, the Vietnamese regular army (PAVN) was extremely well equipped with some of the latest Soviet and Chinese equipment. Hanoi was one of the most densely defended anti-air spaces in the world (because the Americans insisted on trying, again, to kill civiliasn to get them to surrender, which never works), with top notch systems. The PAVN had mechanised batallions with tanks, armoured personnel carriers, anti-tank missiles, even amphibious tanks. The air force also had pretty good quality fighters.

The VietCong on the other hand was a guerilla force equipped only with light and mobile equipment.

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

#328

Post by ricardobeat »

bluescrn wrote: post #254
jacquesm wrote: post #157

Earlier quoted context omitted.

With a 3D printer and some 'ordinary household chemicals' to quote a certain movie you can do pretty scary stuff.

People can do very scary things with a knife, a car, or petrol+matches. We don't try to regulate those things out of existence like we do with new technology (drones and now 3D printers) Kind of ridiculous that a country with more guns than people and 45k firearms deaths per year wants to regulate 3D printed plastic. Yet collecting and shooting actual guns is still an acceptable hobby in many states.

Can a rocket be used to cut your food, take you to the supermarket or power your car?

I'm completely against regulation of any sorts on 3D printing, but you have to admit there is a huge difference in purpose there.

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

#329

Post by dgroshev »

Animats wrote: post #324
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…

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 needed, and discarding the produced ammunition after a year would be incredibly wasteful.

Neither Ukraine nor Russia can defeat each others' air defence networks. The US has a lot of experience doing just that, while successfully defending against ballistic missiles. High tier capabilities matter.

The Patriot in 1980 is a very different system from the Patriot that is fielded today. Between PAC-2 and PAC-3, AN/MPQ-65A and LTAMDS it's a cutting edge air defence system. The progress is constantly incorporated.

The Stinger is a bit old, but mostly because the US doctrine has few uses for it. Regardless, NGSRI is coming.

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

#330

Post by Mars008 »

swiftcoder wrote: post #200
clbrmbr wrote: post #171

I strongly object to building weapons. It is not right. Raise your consciousness, young hacker. I grew up building homemade rocket engines to power model rockets. I even programmed a flight computer in ASM. I was always quite risk averse and, then being only shortly after 9/11, I told my friend I worried what we were doing may be illegal or otherwise get us in trouble. So he picked up the phone and called the county…

> I strongly object to building weapons. It is not right. I used to object to building weapons. Now the EU is engaged in a proxy war with Russia, and the US has repeatedly threatening to annex Greenland. Suddenly the need for a domestic weapons supply chain does not seem so farfetched

That's what US constitution is all about. The people should have power more than just voting. When they don't have it it's like EU. Even legitimate candidate can be easily taken out like in Romania. EU leaders prized it. None even said sorry when accusations appeared to be fake and intentionally fabricated. In this case even voting power has been taken from citizens. Nobody can do anything about it. Multi-step voting systems is another example of minimizing citizens' voting powers. And no legal (and illegal) way for armed protests. Very safe total control. In EU it's called 'democracy'. For comparison Putin is also democratically rules for 26 years now. At least that's what their media tells.
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