Shahed drones have increased in altitude from ~500m at the beginning of the Ukraine war to 2000-3000m, which is a 4x reduction in noise on the ground. The higher the drones are, the less noise they make at ground level, and the less effective this ground-based microphone system will be. The drones have moved to elevations to make them more difficult to target with ground based weapons. Reductions in ground noise are a secondary effect.
The latest versions of Shahed can reach 5000m in altitude, which would largely be inaudible on the ground.
At those higher altitudes they are trivial for radar to detect, and from farther away too. They are adapting cheap commodity used marine radars to get this done in some places
I suspect the Shaheds are going higher to mitigate AA ground fire. Higher up you have to send a missile or interceptor up.
And interceptors are more expensive than Shaheds. A $100k interceptor (guessing here) to shoot a $10k Shahed can be an acceptable deal for the side launching the Shaheds.
It's not about "can reach", it's fairly easy to get them to fly even higher. It's about danger of interceptors vs danger of detection. Today's Ukrainian detection network (based on radars) is so dense there is no way to hide from it anywhere, anyway, so high altitude wins.
Interceptors are battery powered and their energy budget and thus range suffers if they have to climb high.
Detection is facilitated by radar, low altitude means flying under the radar (due to curvature of the Earth) - except radar network is now so dense, it in practice can't work anymore. So they can fly low or high they will be detected anyway - but flying high reduces interceptor's reach and makes intercept geometry harder, giving them better chances to slip through.
The distance to the horizon at sea level, is 5km, a high flying drone only increases that.
With a 25k range and a 10k ceiling, and a stupid low unit cost it is dead easy to deploy this en mass to protect vital infrastructure and deny lower visibility routes (valleys, places where detection range is short).
They (Ukraine) are heavy users of YOLO (image model) that runs on some very low end hardware (sub .35 watt for the most efficient models) - and have shown it to be effective for terminal guidance.
The US has a budget item for 2027, DAWG (defense autonomous war group) - that requested 54 billion dollars. This is larger than the USMC's entire budget. This is a quite admission (another one) that the US is far behind, and the things that are going on in the Ukraine are, terrifying.
Clouds and nighttime are a barrier to visual detection. Even with good effectiveness the conditions needed for that would mean that you have far less than 50% uptime, and your downtime is predictable to your adversary.
A cheap radar takes an order of magnitude less power to run on hardware that is cheaper than an LLM and can see way farther than a camera.
Radar can't effectively see the new low-altitude small fiber optic spool first-person drones that are redefining frontline war.
The solution looks like it's going to be multi-modal (optical + audio) and imperfect. The above poster is correct that an ordinary camera with computer vision (not an LLM, of course) is going to be part of the multimodal defense in depth.
Shahed-type one-way attack drones are important to defend against, but not as impactful in terms of frontline body count, given they just slam into a pre-programmed target.
If these Shahed drones have a propeller they should have a brutal signature between 0-250Hz as they are moving a lot of air. And if the engine speed of the Shahed stays constant it will be even easier to detect it ("Angry lawnmower sound".. but that's only the high frequency part of it).
There are extremely sensitive differential pressure sensors (like SDP600-25Pa) available from Sensirion that aren't overly expensive.
Use one differential side and connect it to a kitchen funnel for directional listening the other one to a plastic bottle with a tiny hole in it. This way the sensor will "Null" out the environmental pressure (which the bottle follows very very slowly) from both inputs. It then only will pick up everything high frequency which is left over (and the bottle cannot follow because of its small hole).
This way I was able to detect washing machines that have a physical link to a house from many hundred meters (machine spinning -> house wall shaking -> pressure waves) away. The speed pattern of washing machines when spinning is very unique (several steps over many seconds).
Add this with some GPS PPS frame timestamping and you should have a nice tracking network that doesn't require a lot of bandwidth. But maybe the setup must switch to analog differential pressure sensors as these Senirion-I2C sensors do not have a Sync ping for super precise timestamping.
> Use one differential side and connect it to a kitchen funnel for directional listening the other one to a plastic bottle with a very very small hole in it. It will pick up everything high frequency that's different to the environmental pressure.
Nevermind drones, and war, that's all fine; but I need to know more about this. Is there a phrase or name for this I could use to find more information, maybe example schematics?
Interesting! There are a lot of super loud cars in my urban area. I want to catalog where and when they drive, so I can stand on the side of the street and shake my cane at them.
I’ve always dreamt of building a mesh network of loud vehicle detectors that would map current loud noises and track where loud vehicles live, coupled with very powerful parametric speakers. So when e.g. the network detects a loud motorcycle at 3am anywhere in town, that live sound is instantly played at high volumes targeting only homes where other loud vehicles live.
Somehow there has been little VC interest in this idea.
Theoretically wind can be Nulled with a 4-way water splitter that are placed in 90° angles (+ a connector at the bottom to the sensor). As long they are orthogonal the wind pressure coming from one side will cause a counter-pressure on the opposite.
Only pressure waves coming into all holes at the same time will reach sensor.
Never tested it. Only a Gedankenexperiment as Einstein would say.
The SDP600-25Pa speaks I2C and only has a handful of commands.
Just read it out with a microcontroller you love (like ESP32) and send the samples to a host for analysis. The ESP32 has limited I2C time stretching capabilities limiting it in the highest resolution modes of the sensor - but often that's not a big factor.
To not overwhelm the poor processor and Wifi maybe better a bunch of frames (like 512 or more).
Yes. But they usually are not performing very good between 1-250Hz.
Sensirion is using a thermal flow-sensing principle method which is basically a heated plate that cools/heats up when air passes it - making it extremely sensitive in this range.
Spam specifically means (at least originally) so much unwanted traffic that it overwhelms legitimate traffic. So can I see why that commenter might have considered it a contradiction to say "the majority being truthful" as a strategy to deal with spam.
The name comes from a Monty Python sketch where "SPAM!" is being sung so loudly that it drowned out any other conservation.
Multi billion dollar spend to “see” $2,000 aircraft and try to shoot it down with multi million dollar equipment.
The speed to produce and cost effectiveness of these drones are seemingly at a massive advantage right now vs Defense capabilities and straight up cost and looks to be that way for a good while.
Sounds like a simple app with mic input being sent to a yamnet-like audio classification model for a single target detection. Hardly anything innovative?
I believe Ukrainians had already deployed such a system. This is specifically designed to use old Android phones already sitting in a drawer somewhere without any other use, and most importantly by anyone without technical skills.
The Ukrainian system isn't open-source. Not a lot of defence tech is.
I don't know about condescension, but a degree of grounding is in order, I believe. European sense of defence is waking up, but it still needs a lot of stimulation, and patting ourselves on the back for some volunteer work is not that.
So, knowing this, but also for more reasons, it absolutely makes sense for Lithuania to not neglect its capabilities, and that includes start-ups that want to be supportive here.
> If we're serious about defence, cooperation with Ukies and expansion of the EU defence sector is the way.
So at which point has the war been about other countries? Lithuania is not at war and it makes no sense to assume that every other country but Ukraine is clueless.
> Phones against windows will not deter ww3.
Aha. So pray tell and explain what your plan is against nukes.
Russia is murmuring that the Baltics let Ukraine use their airspace for offensive drone operations against Russia. And a lot (all?) of the crashed drones have been confirmed by Lithuania to be Ukrainian, although it's alleged that it's Russian jamming driving them off course.
I don't understand what you're saying. What do you mean by comparison? I don't think that every other country but Ukraine is useless. What makes you say that? What are you saying about nukes?
Your comment compares Lithuanian homebrew tech to Ukrainian military-funded tech and claims that the former is grossly inferior to the latter. That comparison is what they're challenging.
> What are you saying about nukes?
According to your comment, homebrew tech was not going to prevent World War III. This can come across as unconstructive because in general, even small things can make a difference (or be a first step towards something that will.)
Their comeback "explain what your plan is against nukes" is just another way of saying "your comment just dismissed an idea but failed to present a better idea on its own," or more generally, "let's remain constructive."
The latest versions of Shahed can reach 5000m in altitude, which would largely be inaudible on the ground.
I suspect the Shaheds are going higher to mitigate AA ground fire. Higher up you have to send a missile or interceptor up.
It’s a trade off.
Sending up a plane that costs $500/hour to operate to take down a few Shaheds an hour works out really well.
YouTube has plenty of videos of these guys going up and just shooting them out of the air.
What's with that "vs" trade-off?
You're saying avoiding detection requires high altitudes.
What do interceptors have to do with that?
Detection is facilitated by radar, low altitude means flying under the radar (due to curvature of the Earth) - except radar network is now so dense, it in practice can't work anymore. So they can fly low or high they will be detected anyway - but flying high reduces interceptor's reach and makes intercept geometry harder, giving them better chances to slip through.
The distance to the horizon at sea level, is 5km, a high flying drone only increases that.
With a 25k range and a 10k ceiling, and a stupid low unit cost it is dead easy to deploy this en mass to protect vital infrastructure and deny lower visibility routes (valleys, places where detection range is short).
They (Ukraine) are heavy users of YOLO (image model) that runs on some very low end hardware (sub .35 watt for the most efficient models) - and have shown it to be effective for terminal guidance.
The US has a budget item for 2027, DAWG (defense autonomous war group) - that requested 54 billion dollars. This is larger than the USMC's entire budget. This is a quite admission (another one) that the US is far behind, and the things that are going on in the Ukraine are, terrifying.
A cheap radar takes an order of magnitude less power to run on hardware that is cheaper than an LLM and can see way farther than a camera.
The solution looks like it's going to be multi-modal (optical + audio) and imperfect. The above poster is correct that an ordinary camera with computer vision (not an LLM, of course) is going to be part of the multimodal defense in depth.
Shahed-type one-way attack drones are important to defend against, but not as impactful in terms of frontline body count, given they just slam into a pre-programmed target.
I may have even discovered it from hacker news, I forget now.
There are extremely sensitive differential pressure sensors (like SDP600-25Pa) available from Sensirion that aren't overly expensive.
Use one differential side and connect it to a kitchen funnel for directional listening the other one to a plastic bottle with a tiny hole in it. This way the sensor will "Null" out the environmental pressure (which the bottle follows very very slowly) from both inputs. It then only will pick up everything high frequency which is left over (and the bottle cannot follow because of its small hole).
This way I was able to detect washing machines that have a physical link to a house from many hundred meters (machine spinning -> house wall shaking -> pressure waves) away. The speed pattern of washing machines when spinning is very unique (several steps over many seconds).
Add this with some GPS PPS frame timestamping and you should have a nice tracking network that doesn't require a lot of bandwidth. But maybe the setup must switch to analog differential pressure sensors as these Senirion-I2C sensors do not have a Sync ping for super precise timestamping.
Nevermind drones, and war, that's all fine; but I need to know more about this. Is there a phrase or name for this I could use to find more information, maybe example schematics?
I'm 99.5% sure if you throw Claude with a datasheet on it will Slop out working code for a ESP32 with ESP-IDF.
Somehow there has been little VC interest in this idea.
Curmudgeon Ai?
My experiments never had a dependency on linearity.
Only pressure waves coming into all holes at the same time will reach sensor.
Never tested it. Only a Gedankenexperiment as Einstein would say.
The SDP600-25Pa speaks I2C and only has a handful of commands.
Just read it out with a microcontroller you love (like ESP32) and send the samples to a host for analysis. The ESP32 has limited I2C time stretching capabilities limiting it in the highest resolution modes of the sensor - but often that's not a big factor.
To not overwhelm the poor processor and Wifi maybe better a bunch of frames (like 512 or more).
Sensirion is using a thermal flow-sensing principle method which is basically a heated plate that cools/heats up when air passes it - making it extremely sensitive in this range.
The name comes from a Monty Python sketch where "SPAM!" is being sung so loudly that it drowned out any other conservation.
https://www.currentaffairs.org/news/how-elon-musk-killed-hun...
And unnecessarily so, to boot. Is the Ukrainian system open source? Can you link to it?
I don't know about condescension, but a degree of grounding is in order, I believe. European sense of defence is waking up, but it still needs a lot of stimulation, and patting ourselves on the back for some volunteer work is not that.
For instance:
a) Lithuania is not at war right now. Ukraine is. So the comparison already does not work.
b) There are drones entering the airspace of Lithuania somewhat regularly; two weeks ago was the last one: https://tvpworld.com/93695919/nato-rafale-jet-shoots-down-dr...
So, knowing this, but also for more reasons, it absolutely makes sense for Lithuania to not neglect its capabilities, and that includes start-ups that want to be supportive here.
> If we're serious about defence, cooperation with Ukies and expansion of the EU defence sector is the way.
So at which point has the war been about other countries? Lithuania is not at war and it makes no sense to assume that every other country but Ukraine is clueless.
> Phones against windows will not deter ww3.
Aha. So pray tell and explain what your plan is against nukes.
Your comment compares Lithuanian homebrew tech to Ukrainian military-funded tech and claims that the former is grossly inferior to the latter. That comparison is what they're challenging.
> What are you saying about nukes?
According to your comment, homebrew tech was not going to prevent World War III. This can come across as unconstructive because in general, even small things can make a difference (or be a first step towards something that will.)
Their comeback "explain what your plan is against nukes" is just another way of saying "your comment just dismissed an idea but failed to present a better idea on its own," or more generally, "let's remain constructive."