Meet Drone Shield, an Ambitious Idea For a $70 Drone Detection System

An anonymous reader writes "Here's an Interesting idea of how to use a Raspberry Pi and a few other inexpensive items to make a low cost detection system. From the article: 'The Drone Shield would combine a Raspberry Pi, a signal processor, a microphone, and analysis software to scan for specific audio signatures and compare them against what known drones sound like. (Because obviously a Predator drone is going to sound very different than a small quadcopter.) Once a match is found, the Drone Shield then sends an e-mail or SMS to its owner...'"

Re:Range

[Anonymous Coward]

Yeah, you'll need some bigger tools [greg.org] for that.

Cardinal vs. Mockingbird vs. Bluejay

[girlinatrainingbra]

This is more likely to work better as a "squirrel" vs. "bird" detector, or with good/better datasets, perhaps even as a "cardinal" vs. "bluejay" vs. "mockingbird" vs. "car alarm" detector, especially if the birds are in your front or back yard. But really, the concept of hearing a predator drone is very farfetched, unless the drone is flying super low for some reason!
.
Better to use this as an auto-logging device for some birders falling in love with counting how many birdies are coming by, or for recording to the exact micro-second when the swallows [wikipedia.org] finally make it back to San Juan Capistrano [wikipedia.org]!

Re:Range

[fluffy99]

So now the highly directional microphone has to be pointed toward the undetected drone in order to detect it? That makes perfect sense.

If you're sophisticated and have multiple microphones in a well planned array, then you can aim your microphone in software and sweep the sky looking for the signature. Look up acoustic beam-forming. If the array is large enough you can estimate distance as well as angle. The bonus is that you get actual tracking instead of just detection.

The problem would be processing power though. Simple implementations could range from 4 microphones that you sum/subtract to look at quandrants, up the way to something approaching what the US Navy does with its towed arrays. I doubt the PI could handle the processing of the signals in both the time domain to get tracking, and the frequency domain to do target qualification.

Of course you also have the question of what do you do when you detect one? Aim a camera at it? Fire off your green laser? (no not suggesting you commit a felony).

Re:And then what?

[AK Marc]

The greatest use of drones is still reconnaissance. So you stop doing the illegal things until it's gone. Why run from a camera? Just hide your activities until it's gone.

Re:Predators are so cheap, everyone can have one!

[anubi]

Its not like we think our Government wants to spy on us because they think we intend them harm.

I think its more down the line of : You just fixed your patio cover. Did you have a permit to do that (fee)? Did you have it inspected by the city inspector ( another fee ). We need to re-do your property tax!

And gee whiz, what if someone is hanging their wash in the back yard on a clothes line instead of using a dryer!

Re:Bigger tools -- was Re:Range

[KGIII]

I don't think that I disagree with your ideals. Having said that, and - really, I don't disagree with them in all likelihood, I must ask, "In which way(s) are you asserting that drones, or their use(s), illegal to start with? What, specifically, is illegal about drones? What laws are being broken with them?"

I ask because, well, I fear that they will become so inexpensive to operate (including training) that they will be used to increase surveillance which, while against my ideals, probably doesn't (in and of itself) violate any laws. I'd like to be able to make a clear, factual, and reasonable argument against the increased use of drones but I don't have any arguments to make against it that are logical and truthful. I can only state that I'm afraid of what it may turn into.

Even in my worst imagined fears concerning these drones, I'm unable to find any laws that are being broken. Perhaps you come from a different country than I do? I'm from the United States of America. We're not all that free here which means that there are a lot of laws. Given the number of laws it is impossible for me (I'm not a lawyer, even then it would still be impossible) to know all of the laws. However, I'm reasonably aware of the many laws that we have to protect us and I'm reasonably aware of the laws that the government must follow and I'm unable to point to anything specifically about drones (or their proposed use, or even with the uses that I'm afraid of) which are illegal.

So, I'm not asking you to be my research assistant or the likes. You stated that drone use was illegal which isn't very specific and certainly isn't true so I'm hoping that you have something more concrete and that you can actually point out which laws being broken by these. If you could provide specifics and case law that would be most excellent too but I'm trying to not ask for too much.

See, in my opinion, they are making their surveillance too intrusive and too easily accomplished. In this day and age we're able to be monitored in most everything we do and, while this has always been legal, it has become increasingly easy for this to be done and for this information to be shared. The use of drones by police, municipalities, and private companies to monitor, photograph, and track a person is just yet another step in the age of zero privacy. I'm quite certain that it (that portion specifically) is legal though I'm equally certain that it shouldn't be. I can vocalize, express, this as a worry and all and that may affect the opinions of some but if it is illegal then there's an even greater chance of demonstrating the harm that this can cause to society.

I don't know... Perhaps you meant it should be illegal? I'm really unable to find anything that indicates the use of drones would be illegal in and of itself and that includes FAA regulations and the likes - I've looked. I could be missing something. Then again, this is /. and you could just be an insane zealot who thinks that anything they don't like is illegal but I'm hoping you're more honest and logical than that. Trust me on this, I've seen it here before...

Either way, I'm hoping you have something more concrete than the generic statement that the use of drones is illegal because, well... No, no it isn't illegal in and of itself. If there's some specific manner that they're being used that is illegal then I'm quite interested in knowing what it is. Like I said, I've even met people online who thought that DST (Daylight Savings Time) was illegal so you could just be one of the crazy ones but I'm sort of hoping you're not. It would be, admittedly, amusing but it wouldn't actually be beneficial to me.