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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

#371

Post by dgroshev »

littlestymaar wrote: post #360
dgroshev wrote: post #288

Earlier quoted context omitted.

Half of munitions missing means doubling the logistical burden of delivering the munitions to where they need to be employed. The trucks/plains/ships that carry your munitions need to be fuelled and protected, too, so the expense is super-linear, especially when it's a distant war and not a war fought on the country's own soil, like in Ukraine. Cheap munitions sometimes explode before they are launched, killing crews…

> Half of munitions missing means doubling the logistical burden of delivering the munitions to where they need to be employed It means doubling the transport capacity, but not doubling the burden. A bunch of crates carrying 155mm shell (cheap munitions) is much easier logistically than a PAC-3 missile for the same weight. > Cheap munitions sometimes explode before they are launched, killing crews and destroying plat…

> It means doubling the transport capacity, but not doubling the burden

Which is my point, doubling the capacity at the end of the spear is more than double the burden. The scale is superlinear. The further out the front is (for the US, it's over at least one ocean), the more superlinear the scaling is.

> but it's not proportional to cost

You might've heard of the cheap North Korean shells exploding in barrels, destroying Russian howitzers. It is indeed very disproportional, that's why spending severalfold on better shells is a great tradeoff.

> You'd launch two at the same time to take the possibility of failure into account

It depends on the ability to launch two. Oftentimes it's impossible; cheap FPV drones interfere with each other, or maybe you don't have double the planes to fly CAS.

> how they are being employed today in Ukraine

It's logistically impossible to employ the kind of drones Ukraine is employing on the go and organically to infantry. Features and CONOPS that enable organic employment lead to a substantial increase in per-unit prices, see Rogue 1.

> A Magura isn't a missile, but it has shown its capability of completely shutting down the Black Sea Fleet.

It's three Black Seas worth of distance between Guam and the Taiwan strait. On top of that, nowadays those boats are pretty effectively countered. Overindexing on the war in Ukraine would be a mistake.

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

#372

Post by vidarh »

dgroshev wrote: post #370
vidarh wrote: post #367

Earlier quoted context omitted.

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

> a missile that can hit something a hundred kilometres away

At no point did I mention "a hundred kilometres away"

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

#373

Post by neoinkarasuyuu »

mothballed wrote: post #150
mikkupikku wrote: post #77

Earlier quoted context omitted.

MANPADS are certainly covered by ITAR. It could probably be effectively argued by his lawyers that what he has created isn't truly MANPADS but rather just an edgy toy that superficially resembles a weapon system but isn't actually capable of performing as one. Maybe that would work, but I think his chance of getting dragged into the legal system for this or for some chickenshit like weed possession are very high, par…

https://www.law.cornell.edu/uscode/text/18/2332g states that just having a system "intended to launch or guide a rocked or missile described in... [description of MANPAD type rocket]" carries life imprisonment. He calls it a manpad and then shows a system intended to launch it. There is no consideration in the law whether he actually plans to use it or ever meant any violence, nor any consideration of whether it viol…

I don't see how this system matches the description of subparagraph (A). The missile is fed a static gps coordinate at launch via the umbilical, and has no mechanism in the missile or launcher to "seek or proceed toward energy radiated or reflected from an aircraft or toward an image locating an aircraft" or "otherwise direct or guide the rocket or missile to an aircraft", which is the requirement in subparagraph A.

INAL, so I would like to understand why you think this applies?

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

#374

Post by jijijijij »

bragr wrote: post #85
shrubble wrote: post #69

Earlier quoted context omitted.

Consumer GPS chips are specifically nerfed for using them in rockets; they give erroneous readings on purpose if altitude is above a certain height and/or if speeds exceed a certain speed. That’s likely why the mid-course correction software uses other methods.

The restrictions on GPS prevent ballistic missiles, not MANPADs. Typical limits are 515 m/s and 18,000 meters (try using your phone's GPS on a commercial flight, it works fine near a window). Update rate is probably the biggest issue with GPS and MANPADs.

Are these chips so much better at calculating GPS position than general purpose CPUs or consumer FPGAs? Feels like a silly restrictions for anyone capable of building a ballistic missile. On the other hand it seems relatively computationally expensive to do a speed check every time for low energy devices.

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

#375

Post by jijijijij »

ninjagoo wrote: post #124
nekusar wrote: post #109

Earlier quoted context omitted.

Chinese GPS chips dont have those restrictions. I even have 1 that can remove up to 8 active jamming signals. Gotta love what you can buy for $20

It would be interesting to see if those are only for external sale vs restricted for sale within China. If China allows those unrestricted chips to be sold internationally but not domestically it would be a strategic long-term decision, I would think. Destabilize the neighbors but not themselves. The more likely reason is that their government has simply not gotten around to restricting it.

I mean, do you have the impression they are destabilizing anything with this (implying these GPS restrictions are actually needed)?

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

#376

Post by m4rtink »

gorgoiler wrote: post #244
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…

I believe there was a similar weapon being developed in the west, only recently, which involved a missile with contra rotating halves joined by a clutch. The fixed fins caused it to always steer one way. It flew straight by releasing the clutch to spin up the front half, negating the steering effect. Grabbing the clutch caused it to stop spinning and veer off in one direction. Presto! Two axis continuous flight contr…

I think the Ukrainian Stugna & other ATGMs (not only with soviet heritage) use the rotation trick - you get some stabilization for free, might need less control surfaces and maybe even simpler sensors.

IIRC in the Stugna case, they even use solid fuel micro motors - they have a couple dozen of them in a rignt near the nose and fire them as the missile rotates in flight providing a kick in the right direction to hit the target. Given the missile usually flies for <30 seconds, this is perfectly adequate versus a complex set of aerodynamic actuators.

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

#377

Post by m4rtink »

pjc50 wrote: post #209
laborcontract wrote: post #45

Earlier quoted context omitted.

soo... i have no kept up with what's gone on in russia/ukraine. Are those drone videos what i think they are – drones sneaking up on humans and, presumably, ceasing them of life? edit: Ok, I googled the guy > I have read the works of authors such as Jean Baudrillard, Desmod Morris, and Ted Kaczynski who believe that technology is harming us and the world. https://wiki.opensourceecology.org/wiki/User:Alisherkhojayev

> have no kept up with what's gone on in russia/ukraine https://en.wikipedia.org/wiki/Casualties_of_the_Russo-Ukrain... "between 400,000 and 1.5 million estimated casualties (killed and wounded) during the Russian invasion of Ukraine from 24 February 2022 to November 2025" Mostly due to artillery. Both sides are firing in the region of 10,000 155mm shells per day. For years.

I think this is likely quite outdated by now - a lot of artillery is definitely still is use now, but there is also a very large gray zone dozens of kilometers around the front line where remote controlled UAVs (usually single use FPVs and reusable bomber drones) will quickly identify and strike anything that moves.

Due to that I have seen many people monitoring the war to estimate that drones are now causing more casualties than artillery - both due to being much more precise & by forcing artillery to move further back & fire less from the gray zone to avoid itself being destroyed by drones.

In any case things are moving pretty quickly & the current state is very different than just a year or two ago.

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

#378

Post by mothballed »

neoinkarasuyuu wrote: post #373
mothballed wrote: post #150

Earlier quoted context omitted.

https://www.law.cornell.edu/uscode/text/18/2332g states that just having a system "intended to launch or guide a rocked or missile described in... [description of MANPAD type rocket]" carries life imprisonment. He calls it a manpad and then shows a system intended to launch it. There is no consideration in the law whether he actually plans to use it or ever meant any violence, nor any consideration of whether it viol…

I don't see how this system matches the description of subparagraph (A). The missile is fed a static gps coordinate at launch via the umbilical, and has no mechanism in the missile or launcher to "seek or proceed toward energy radiated or reflected from an aircraft or toward an image locating an aircraft" or "otherwise direct or guide the rocket or missile to an aircraft", which is the requirement in subparagraph A.…

I'm no lawyer either but he literally calls it a "MANPADS Rocket and Launcher prototype."

Look up MANPADS[1] and find out what that is, it appears to pretty clearly satisfies (A).

Then look at (B) and note a launcher that merely intends to launch something that satisfies (A) counts, and then note he straight up calls it a MANPADS launcher prototype. There is no requirement that it actually be capable of doing so.

Also note in his other short, the guy shows a network of cameras doing tracking of a drone[2] and claims that is an intended guidance system. He claims the guidance is updated to the rocket while in flight, with his diagram clearly showing the target as the emblem of an aircraft.

[1] https://en.wikipedia.org/wiki/Man-portable_air-defense_syste... [2] https://www.youtube.com/shorts/85oI725HPPU

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

#380

Post by NuclearPM »

steve-atx-7600 wrote: post #308
shrubble wrote: post #60

Earlier quoted context omitted.

The fact that Koresh and his group held off Federal officers who stormed their building with simple guns that anyone can buy, is likely the point. Out of five and a half minutes of video, David Koresh appears for perhaps three seconds. It does put a new twist on the recent controversy about 3d printers needing to be licensed, however.

I think this is within the intent of the 2nd amendment. Having groups of citizens check the power of their government by being armed comes with the the downside of abusive types forming cults. I think this tradeoff is worth it. Mass shooting evens and cults harming people are obviously terrible. But, I prefer living with some of that knowing that it provides recourse for becoming like the majority of Iranians that ar…

The problem is too many of these small government libertarian 2nd amendment people are fascism lovers.
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