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

35-ish years ago there was a pitch for cheap, high velocity, spin-stabilized rockets that were deployed in dense pods on the A-10. The rocket's seeker could divert some small amount of thrust at an angle for guidance, but otherwise that was it. I can't recall if it ever made it out of the pilot phase, but obviously nothing new under the sun.

The wobble would only 'scan' a limited field of view, so only if the sun was in that view

That tracks. The defense primes have zero incentive to make things cheaper — their business model is cost-plus. A guy building something for 10k in his garage is an existential threat to programs billing 500k per unit. Of course they ignored him until the geopolitical situation made it impossible to keep ignoring.

If you build a tool optimized for human destruction, you are feeding a system where violence is the default currency

We are heading to robotic wars where abilities and cost efficiency are the key factors. Like today drones in Ukraine war. Attack + defense + automation, + money + production

I wonder what could have possibly sparked that... lol

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.

For a sub-minute flight the drift budget is actually pretty forgiving — a MEMS gyro drifts maybe 1-3 deg/sec, and if you're fusing with accelerometer data you really just need "which way is up" and "am I still pointed at the target." A $5 IMU can hold that for tens of seconds.

Where you're right is repeatability. Mil-spec works the same on launch 1 and launch 500 across temperature extremes. Consumer MEMS you'd need to characterize each unit individually — fine for a demo, impractical at any scale.

Cheap sensors are the future ;) onboard ML can help with signals interpretation.

For different definitions of cheap though.

While the pure gyro/accelerometer stuff does suffer from major problems the improvements in SLAM using just cameras in the last 15 years are insane.

You can calibrate any sensor, its just a manufacturing step, and while cheap ones may be inaccurate and drift over time, I'm pretty sure the good enough ones (which cost tens of dollars, not fractions of a dollar) are accurate enough to work for the seconds-to-minutes flight time of a rocket like this.

But do they drift enough to hit girls schools?

People made self-guided missiles with 1940s technology, in the 1940s. It can't be too much of a surprise if someone right now can make guided missiles in their garage with 2026 electronics. At this point the "guided" feature is trivial, the "missile" part is doable, and the weapon has probably become the tricky part.

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.

What you are likely thinking of is the "selective availability" system, which intentionally provided slightly inaccurate data to civilian clients, while military receivers could decrypt the most accurate info. But this has not been used for many years now.

Other than that, GPS is a one-way system, it does not know you exist, how fast your receiver is moving or "give" different information to one client vs another.

Even if it did, this is essentially a toy and moving slower and lower than a general aviation plane.

It uses accelerometers and other sensors because they can be sampled and integrated hundreds of times a second. The $5 gps module is 9600 baud serial and provides one update/second (or maybe 5/sec depending on which part number you pick).

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

3d printed PLA and spiral wound cardboard is generally fine for hobby rockets, until they start going supersonic - then you need metal.

I'm not sure the launch tube could withstand the heat of the rocket exhaust though. Although that might depend what it is printed with.

People have been doing 3d printed model rockets for a while now. With no payload they experience higher acceleration than this will.

Seems like the quick fix is to rebrand this from "MANPADS" to "anti-tank", right? Then it would just be a standard destructive device?

It’s really odd how people will so easily fixate on the bone the government consisting of maniacal, narcissistic, psychopathic, pathological liars will throw them; while totally ignoring that the pathological lying, evil, murderous people in and of the government are constantly and ceaselessly, lying and murdering.

There now carpet bombing and murdering people in Iran, just like they mass murdered people in Gaza, and they’re doing it to cover up and distract from the fact that our government consists of raping pedophiles. That is who we are governed by. … but David Koresh excuses it and makes any opposition invalid, of close.

> I think he's trying to make a point about technology enhancing the capabilities of people who are in any conflict with conventionally powerful forces

Which is absurd, since all the technology he used was manufactured by the conventionally powerful forces and they can decide to not sell you their stuff.

Yeah the solution is simple.

Just licence everything private people can buy except (healthy food). /S

Microcontrollers and electric motors are too dangerous for the general public.

Both Russia and Ukraine build millions of drones per year, most of them fpv drones that are basically remote controlled flying grenades. There's plenty of electronic warfare with radio jamming, so in some places they use drone mounted spools of fiber optic cable to control them. It's probably been the most impactful weapon type in the war for the past years.

> 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.

Yes. Both sides are using explosive FPV drones, flown directly into soldiers (as well as other forms of drone warfare.)

We might need them. Would be better than my theory that this country will recover at some point after they destroy the EPA and reintroduce leaded gas because that's what made this country great which leads to a generation of kids who are willing to throw bricks at cops again.

It is exciting to know a secret no one else does. David vs Goliath stories have always been powerful. It is seductive to think you have outsmarted the rest of society.

Be careful who you let manipulate those emotions.

The white washing of Koresh is sickening to see. Similar to how some in the US idolize the traitor Colonel Robert E Lee.

I suspect a major problem is the quality and consistency of the propellant and getting a symmetric burn.

The video references "future tracking systems," so I don't think it aims at all yet.

> curious lack of any data regarding the actual accuracy of the system

No lack of entrackment data generated by [edit] d̶i̶g̶i̶t̶a̶l̶ ̶t̶w̶i̶n̶ github repo of "the system".

I always wonder why rockets are millions of dollars each, that seems insane to me.

I've been subscribed to this guy for some time. His work is much more impressive, and IIRC, he either works for a defense contractor or is studying for that.

I think there's lots of people talking past each other on this post. These kinds of designs won't be as reliable as the existing designs, and they may have a systemic flaw, for example, susceptibility to disabling with microwaves. And they aren't going to work after sitting in an ammo depot for 15 years in the desert or after being dropped from a plane.

But these designs will cost just a few dollars more than the equivalent dumb munition (and can possibly be retrofitted), and can be two orders of magnitude more effective in the short term. The threat here isn't "guy in garage makes MANPADS", it's "IRGC converts 100's of thousands of existing unguided cold-war rockets into guided S2A and S2S missiles for $20 each". Even if it doesn't hit any target, each aircraft has a limited number of countermeasures and has to return to base if they run out or risk being hit.

Guided munition at a dumb munition price is enough to invalidate many strategies.

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

Exactly. Consider the current conflict in Iran. They have thousands of drones that cost $50k each. The US’s only real defense against one of these drones is to fire a million dollar missile at it. That assymmetry can win or lose a war.

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?

> I think the propulsion system will be the easy part.

Really? I think rocket science is still not easy. Just look at how much nation states are spending on maintaining their liquid and/or solid fuel rocket programs. If they even have one, let alone both.

This book might give some insights into the why https://library.sciencemadness.org/library/books/ignition.pd...

Quote: "All this sounds fairly academic and innocuous, but when it is translated into the problem of handling the stuff, the results are horrendous. It is, of course, extremely toxic, but that's the least of the problem. It is hypergolic with every known fuel, and so rapidly hypergolic that no ignition delay has ever been measured. It is also hypergolic with such things as cloth, wood, and test engineers, not to mention asbestos, sand, and water —with which it reacts explosively. It can be It has recently been shown that an argon fluoride, probably ArF2, does exist, but it is unstable except at cryogenic temperatures.

[...] kept in some of the ordinary structural metals — steel, copper, aluminum, etc. —because of the formation of a thin film of insoluble metal fluoride which protects the bulk of the metal, just as the invisible coat of oxide on aluminum keeps it from burning up in the atmosphere. If, however, this coat is melted or scrubbed off, and has no chance to reform, the operator is confronted with the problem of coping with a metal-fluorine fire. For dealing with this situation, I have always recommended a good pair of running shoes."

Granted this is about a fuel that is AFAIK not used for MANPADs, but the joke about the running shoes could be made about most aspects of rocket propulsion.

Even if the correct sensor could be chosen (whatever it is), unlikely is attainable by consumers and the technology would definitely be export controlled in the US.

> Realistically, I doubt there’s ANY system out there will be able to counter small weaponized drones that are flown manually let alone with AI, you might have some workarounds, but never a real counter.

Weaponized drones (say D_A) can be countered by other weaponized drones (say D_B), equally cheap or cheaper than D_A because the D_A is usually targeting something larger (so more payload) and typically has a longer range. D_B only needs to wreck D_A at a shorter defensive range. That's what Ukraine is doing.

You can also use drone swarms with coordinated action so that each drone in the swarm is only targeting one other drone, and automatic re-targeting if one node misses. [1]

[1] https://en.wikipedia.org/wiki/Swarm_robotics

I don’t know if it will work, but here’s a startup that seems to be building an AI-controlled shotgun:

https://www.ycombinator.com/companies/9-mothers-corporation

Given the war in Ukraine, wanting to build such things is certainly understandable. But still, this is the stuff of nightmares.

"Realistically, I doubt there’s ANY system out there will be able to counter small weaponized drones that are flown manually "

Why would lasers not work?

Those cheap drones are made from plastic, if you have a laser powerful enough and a target guidance system (like a camera and a PI) - then you would just need enough of them.

From what I can tell, Ukrainians are having some success with converting guns into automatic turrets that can track and shoot down drones via sensors, and the rifle-equivalent of birdshot.

"let alone with AI" what's falling into the AI category here perhaps is the key question, since microseconds counts, and LLM are very slow!

Even the fastest "real-time" LLM frameworks currently report sub-second latencies around 120ms. This is fine for high-level mission planning (e.g., "fly to the red house") but too slow to prevent a drone from hitting a tree at 50mph (80 KM/h)[1]

Whilst the Shahed-136 kamikaze drone typically flies at a maximum speed of around 185 km/h (roughly 115 mph or 100 knots).

[1] https://arxiv.org/html/2602.19534v1 [2] https://en.wikipedia.org/wiki/HESA_Shahed_136

> Realistically, I doubt there’s ANY system out there will be able to counter small weaponized drones that are flown manually let alone with AI

What kind of systems are you thinking about? Jet airplanes for sure are completely safe from small drones.

I mean, if we already "trust" nations with that power...

My understanding is that for the civilians in Ukraine Shaheed style drones are the danger.

So far russia launched over 57 000 Iranian/inspired shahed drones. They are like 6ft long drones with 40+ lbs payload with couple hundreds of miles of range.

USA/NATO/allies heavily rely on Patriot AA system. Even if you disregard the prohibitive 100x cost difference, there are about 2500 Patriot compatible PAC missiles.

This is why gulf states are scrambling to get their hands on cheap alternatives - Ukraine manages to shoot down over 90% of all drones heading their way, usually it is over 400 per day in big waves.

>FOV

FPV.

But I really hate the whole weaponization of these FPV drones (as opposed to the bigger fixed wings ones), not just they ruined the fun hobby that a lot enjoy, but also increased the prices for the parts. Before 2022 whenever I talk about drones everyone is enthusiastic about them, what benefits they can bring like drone deliveries and all, after that, you get a hostile reaction or the government putting you on some watchlist.

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 violates ITAR.

As someone who has a lot of interest in weapons law, this is probably about the only kind of weapon that can't be even legally contemplated in the USA, worst case for almost anything else you can get an NFA stamp. The USA is absolutely paranoid about yielding their air power so they come down like a ton of bricks against anyone that might want to defend against that.

You can also blow your hands off, blind yourself and/or burn down the building. So be very careful if you try this. Note it is illegal to make your own solid fuel motors in some countries (you need a special license in the UK).

That's why it's so important for people who can hold a moral line, to do so. Violence breeds violence.

A good engineer in America can afford avoiding weapons work.

But in Canada we ...

Oh shit. You're right.

Clawjet, secured with sandboxing, bring your own SKILLs.

this is not funny yall!

that's lit