Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

Lithuanian startup launches open-source network to detect Shahed-type drones

lrt.lt

Post reply on HN
Print view View original

41–50 of 104 posts

Re: Lithuanian startup launches open-source network to detect Shahed-type drones

#41

Post by MiracleRabbit »

amluto wrote: post #38
MiracleRabbit wrote: post #14

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 expensiv…

What’s the frequency response of that sensor? The datasheet says nothing.

Honestly: don't know.

My experiments never had a dependency on linearity.

Re: Lithuanian startup launches open-source network to detect Shahed-type drones

#42

Post by dghlsakjg »

tristanj wrote: post #6

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…

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.

It’s a trade off.

Re: Lithuanian startup launches open-source network to detect Shahed-type drones

#43

Post by brookst »

Hnrobert42 wrote: post #22
MiracleRabbit wrote: post #14

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 expensiv…

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.

Re: Lithuanian startup launches open-source network to detect Shahed-type drones

#44

Post by quietbritishjim »

embedding-shape wrote: post #31
sourcegrift wrote: post #11

Earlier quoted context omitted.

[flagged]

"Unwanted traffic", is what I go by typically. What is your understanding (if you have one) of that term?

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.

Re: Lithuanian startup launches open-source network to detect Shahed-type drones

#45

Post by warumdarum »

Hnrobert42 wrote: post #22
MiracleRabbit wrote: post #14

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 expensiv…

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.

https://freesound.org/people/PicassoCT/sounds/850225/

Curmudgeon Ai?

Re: Lithuanian startup launches open-source network to detect Shahed-type drones

#46

Post by brookst »

nefarious_ends wrote: post #20
Avicebron wrote: post #13

Earlier quoted context omitted.

As much as I like to point and guffaw at "bad evil rocket man" the from orbit bit is doing a massive amount of lift (pun not intended) for that price.

[flagged]

[flagged]

Re: Lithuanian startup launches open-source network to detect Shahed-type drones

#47

Post by Hackbraten »

dmos62 wrote: post #37
shevy-java wrote: post #21

Earlier quoted context omitted.

That statement made ignores several facts. 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 i…

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?

> What do you mean by comparison?

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."

Re: Lithuanian startup launches open-source network to detect Shahed-type drones

#48

Post by vintermann »

shevy-java wrote: post #21
dmos62 wrote: post #15

[flagged]

That statement made ignores several facts. 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 i…

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.

Re: Lithuanian startup launches open-source network to detect Shahed-type drones

#49

Post by rdtsc »

dghlsakjg wrote: post #42
tristanj wrote: post #6

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…

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. It’s a trade off.

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.

Re: Lithuanian startup launches open-source network to detect Shahed-type drones

#50

Post by dghlsakjg »

warumdarum wrote: post #12
tristanj wrote: post #6

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…

So film the sky during charging and run a llm on it?

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.

Post reply on HN