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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

#101

Post by daymanstep »

tzury wrote: post #88

There are 2 short segments in the video showing the actual performance and thus far it is a complete [1] failure [2]. The guy has a talent, and he put together a nice prototype based on OpenRocket [3], but with all due respect, this is not a rocket, and you are not going to win any war with this toy, even if all your enemy has are rocks thrown at you from pretty much similar distance. The remix of computer games / Uk…

I'm surprised nobody else has pointed this out. The entire YouTube video has only two short clips of the actual rocket being fired, and in both cases the clips are very short and only show the rocket being fired and then following an erratic flight path, and then get cut before showing the rocket hitting anything.

For all the technical info given in the video, there is a curious lack of any data regarding the actual accuracy of the system. What percentage of rockets tested managed to hit anything and at what range?

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

#102

Post by V99 »

shrubble wrote: post #69
redgridtactical wrote: post #13

The engineering is genuinely impressive for $96, but naming the repo "MANPADS-System-Launcher-and-Rocket" on GitHub is going to attract exactly the kind of attention you don't want. ITAR implications aside, the interesting part is the mid-flight trajectory recalculation on a $5 sensor. That's the same basic problem military guidance systems solve with hardware that costs thousands. The gap between consumer electronic…

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.

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).

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

#103

Post by condensedcrab »

lukan wrote: post #100
tamimio wrote: post #92

Earlier quoted context omitted.

And that’s ok if it’s failing to do the job as intended, learning is acquired, and it looks fun to build, I am in the field and I find it great homemade concept. 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.

"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.

At long distances the small cross section of the drone requires tight focusing (expensive optics) or a high power, preferably pulsed laser (expensive laser) or both.

Not impossible but many times more expensive than the drone

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

#105

Post by kikkia »

Really cool work on making your own rocket motors.

I wonder why he calls it a MANPADS (Man portable Air Defense System) It does slightly resemble a Manpads, but with a GPS based guidance system it would not able to be used for air defense, even conceptually. Typically manpads would use something like an infrared/optical or radar guidance system which would run way more than $5. This does seem like a cool home made AGM-176 or similar. There's always been a side project idea in the back of my head about what the cheapest IR or laser guided RC Plane launched rocket would look like. A cheap rocket design powered by some model rocket engines that could be used for a drone -> drone intercept cheaply.

Awesome job taking a fun idea into reality. It's really impressive to see the design work

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

#106

Post by ninjagoo »

tzury wrote: post #97
tamimio wrote: post #92

Earlier quoted context omitted.

And that’s ok if it’s failing to do the job as intended, learning is acquired, and it looks fun to build, I am in the field and I find it great homemade concept. 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.

"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 dro…

> "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!

LLMs (Large Language Models) are far from the only type of AI around. It's a pretty broad field, and there are real-time AI systems, for example, self-driving cars, which have the response times you're thinking of. [1]

[1] https://en.wikipedia.org/wiki/Artificial_Intelligence:_A_Mod...

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

#107

Post by skybrian »

tamimio wrote: post #92
tzury wrote: post #88

There are 2 short segments in the video showing the actual performance and thus far it is a complete [1] failure [2]. The guy has a talent, and he put together a nice prototype based on OpenRocket [3], but with all due respect, this is not a rocket, and you are not going to win any war with this toy, even if all your enemy has are rocks thrown at you from pretty much similar distance. The remix of computer games / Uk…

And that’s ok if it’s failing to do the job as intended, learning is acquired, and it looks fun to build, I am in the field and I find it great homemade concept. 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.

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.

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

#108

Post by danmaz74 »

tamimio wrote: post #92
tzury wrote: post #88

There are 2 short segments in the video showing the actual performance and thus far it is a complete [1] failure [2]. The guy has a talent, and he put together a nice prototype based on OpenRocket [3], but with all due respect, this is not a rocket, and you are not going to win any war with this toy, even if all your enemy has are rocks thrown at you from pretty much similar distance. The remix of computer games / Uk…

And that’s ok if it’s failing to do the job as intended, learning is acquired, and it looks fun to build, I am in the field and I find it great homemade concept. 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.

> 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.

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

#109

Post by nekusar »

shrubble wrote: post #69
redgridtactical wrote: post #13

The engineering is genuinely impressive for $96, but naming the repo "MANPADS-System-Launcher-and-Rocket" on GitHub is going to attract exactly the kind of attention you don't want. ITAR implications aside, the interesting part is the mid-flight trajectory recalculation on a $5 sensor. That's the same basic problem military guidance systems solve with hardware that costs thousands. The gap between consumer electronic…

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.

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

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

#110

Post by MarkusWandel »

It still doesn't cease to amaze me what can be done with modern ultra-cheap electronics. $1 for the accelerometer. $17 for four servos. But as DIY cheap weapon development? Only if the ultra-cheap electronics pipeline will keep flowing.
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