To toss a sensor into the location one wants to have data on often means to put the sensor at risk. It is possible to listen to conversations behind windows by reflecting a laser off the windowpane (which is vibrating from the soundwaves), similarly, it is possible to see through warped glass if the camera is calibrated by filming a known target behind the pane of warped glass.

So i propose a merger of those two concepts: little pressurized helium balloons, with no sensors whatsoever, to be calibrated against known targets. Then the balloons are released, and a camera, laser rangefinder, laser microphone, anything, is trained on it, thereby getting the vantage point of the balloon without actually taking a sensor there. The balloons are pressurized (just half an atmosphere above norm, to stiffen it) so they do not alter shape, and apart from being made from maximally reflective material, it also features some markers that can be used to accurately compute its position in space.
-- loonquawl, Apr 20 2009

Tri Turbofan RC Airship http://www.otherlan...s.co.uk/ufopic3.htm
An example of a modern RC airship product. [Aristotle, Apr 24 2009]

Oh.

I thought this would have something to do with digging out my old peasant garb and sneaking up on a ren fair.
-- normzone, Apr 20 2009


NIce category. The only flaw that I can think of is that if the ballons are released in an area that includes other people talking (apart from the pre-calibrated targets) then the ballons would just pick up incoherent noise.
-- gnomethang, Apr 22 2009


Wait. What? You want to send balloons out with mics on them? You want the balloon to be your sensor, no? You say you aren't sending sensors. Soo... Hmm. Why don't we care about the balloons?
-- daseva, Apr 23 2009


Not quite, [daseva]. The idea is that you can use the balloon as a static waypoint. It's not doing any electronic sensing itself - but some other long range sensor (laser, or camera) is trained onto the balloon to determine changes in it's movement and appearance. The observed data is then used to infer what the balloon 'sees'.

It's a nice concept but the thing that makes it halfbaked is that I think that little helium balloons might be quite conspicous... then again, they might be mistaken for miniature disco balls.
-- Jinbish, Apr 23 2009


[Jinbish], [bigsleep]: Although i realize the applicability in war, i was actually thinking of civilian use -> Biologist wanting to have a quick look on a tree from above, Geologist who'd like to peek into a volcano without bringing their 50k equipment near molten stone, crowd control, aerial images...

[gnomethang]: the noise picked up by the balloon would be the same as a omnidirectional microphone would pick up if situated at the same location - possibly structural adjustments could be made to make it more directional, though.
-- loonquawl, Apr 23 2009


So, the balloon is your sensor, though, literally. It's what you use to make the measurement. I'm just saying. It's a floating potentially omnidirectional sensor. That you then sense. Using lasers. It's all very technical. Why balloon? Why not a little remote controlled helicopter with a window on it? Or better yet. A camera!
-- daseva, Apr 23 2009


By that logic the air around you would be your "real" sensor when you record sound, while the mirror inside your dlsr would be your "real" sensor when taking pictures. the ballon is nothing more than a medium.

RC helicopters produce an appreciable level of sound, so no good for recording, and they cost quite a bit more than plain helium/foil balloons. Taking a camera to where the action is is a variably good idea, depending on the action.
-- loonquawl, Apr 24 2009


For the record you can get small(ish) remote- controlled airships (see link). I make no guarantees for their stealth or stability capabilities.
-- Aristotle, Apr 24 2009


Ah, [lq], I get it. I was too busy thinking along the lines of the spying through a pane of glass and using this for espionage.

Fair enough, you're effectively placing an inflatable mirror somewhere for general observations (not limiting to any specific application) that would otherwise be difficult to get to. (+)
-- Jinbish, Apr 24 2009



random, halfbakery