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Way Of Detecting Humans? Answered

Is there ~~an easy way~~ a best way of detecting humans in the dark, or in a forest? Me and my friends play airsoft, usually in a forest, and it's hard to know where the enemy (other friends) are. I'm a sniper and I want an easy way to detect them. One way would be a thermo-camera, but those are expensive. Is there a better way?


Yeah. Wild planet makes a toy night vision camera for $40. It's actually a viable night vision camera that sees near-visible infrared light. You would be able to see them, but they wouldn't be able to see you. I'm planning on taking mine apart and working them into either some kind of helmet or a pair of goggles. They also have a switch to go between visible light and infrared. You could use them in any scenarios involving dark buildings, or caves, or anything similar. The only issue is that you can only see as far as your IRLEDs shine, but they make some super bright you could get at radio shack that would peobably allow you to see pretty far.

I want to say this came from one of the Evil Genius series of books, but I can't remember for sure.  There was a way to make a very basic thermal viewer that wouldn't break the bank, but it was extremely low refresh rate - something like 10 frames per MINUTE.

Looked workable, though, and pretty easy to build.

you could scatter some ir led's (hooked up to power suplies) on the ground, use an ir camera and if something blocks the light from an led SHOOT! 

Maybe something similar to RADAR or SONAR...

"One way would be a thermo-camera, but those are expensive." Why don't you make a new post and see if anyone has ideas for a cheap thermal camera (preferably compact, in your case)? It's highly unlikely that an individual can make it for cheaper than a manufacturer, but there are plenty of 'ibles where that is not the case. Always worth a shot.

most people just make IR cameras, not thermal. Thermal ones are reallllly expensive because the main component is difficult to manufactuerer flawlessly, plus there's not a huge demand for them

Also, just an idea, but what if you had a camera with a coupled audio output what would emit a whine that is beyond the human range of hearing, but that could be detected by the "camera" and used to construct the night scene. A high pitch wouldn't be good for long distances, but might be better for detail (as in echolocation). I've seen prototype software on the newscientist youtube channel, so it would definitely require a lot of software engineering skillz, but there are lots of people who like a challenge.

 Because camera sensors cannot see "noise" ??

Yes. Audio input. Many cameras have it.

 Lol... but that would only record onto the recording medium (tape/disk/memory stick) the audio that's inputed. The camera still would not be able to differentiate where different sounds were coming from.

Not by default, but there are ways to do it. You would need more than one microphone on the camera and then based on the frequency of each wavelength (and this is only wavelengths around the frequency emitted by the camera which are out of range of the human ear) you would have something determining distance. This is possible and they already have equipment that does it, just not for this sort of thing.

I have no doubt about that, just wasn't sure if someone else who might be an electrical engineer would have any ideas. As for the IR cameras, the ones I've seen on Instructables don't really do what I would consider an IR camera would be capable of doing. I would envision a good piece of IR equipment for this situation being compact, picking up and magnifying IR input like a lot of CCTV security cameras do, and other things like that. A lot of the IR cams I've seen don't really take the kind of IR input you would need. Maybe worth bringing up amongst the community.

it sounds like a challenge indeed, but for echolocation to work wouldn't it take a bunch of microphones to "display" the image in reasonable resolution? I dunno, I'd have to read up on it. But it also sounds like a great deal of data for a common 8 bit microcontroller to handle. Maybe it's time to learn up on 32 bit...

Indeed, you are correct, such an endeavor would be prohibitively expensive. Sad.

Plant a noise-maker (say, a recording of somebody tripping up and going "ow") on a timer, position yourself a few yards away, possibly up a tree.

When the timer goes off, shoot at anything that shoots at the noise-maker.

spread nails, thumbtacks, etc.. everywhere in the woods. shoot at anything that screams in pain

try listing for noises with a noise detecting device works for me or just listen very carfully good luck

i have an idea! get some IR leds form dealextreme, then attach them to an appropriate power supply, then hide the working leds on your friends' clothes. if you get a camera phone, (or any other device that has a camera and a screen) cameras can detect IR light which the human eye cannot detect so in essence, you can see them in the night

i was thinking of doing that, but i think my friends would figure it out pretty fast, and so it'd only work for like 1 round and then never again :P

get an led and a button cell that would be about the size of a quarter

I think it's called a "dog." They have four legs, are covered with hair, and generally emit slobber from their mouths.

yep, I'm going to take my dog where my friends are shooting, good plan

You asked if there was an "easy way." You didn't ask for the "best way," or the "safest way," or anything else. I think you got an answer that was worth exactly what you paid for it :-)

One way would be a walkie talkie where you think they might go by, then you have a general idea. Of course the hidden walkie talkie would be to be taped down so you can hear it.

yeah, at that point why don't i put tracking beacons on them :P

Because a beep beep beep every second kinda ruins their purpose of being unseen.