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Let the world search for the lost

There is a story that Ikonos is going to redirect a satellite to do a high-res shot of the area where CNet editor James Kim is missing in Oregon. That's good, though sadly, too late, but they also report not knowing what to do with the data.

I frankly think that while satellite is good, for something like this, traditional aerial photography is far better, because it's higher resolution, higher contrast, can be done under clouds, can be done at other than a directly overhead angle, is generally cheaper and on top of all this can possibly be done from existing searchplanes.

But what to do with such hi-res data? Load it into a geo-browsing system like Google Earth or Google Maps or Microsoft Live. Let volunteers anywhere in the world comb through the images and look for clues about the missing person or people. Ideally, allow the map to be annotated so that people don't keep reporting the same clues or get tricked by the same mistakes. (In addition to annotation, you would want to track which areas had been searched the most, and offer people suggested search patterns that cover unsearched territory or special territory of interest.)

These techniques are too late for Kim, but the tools could be ready for the next missing person, so that a plane could be overflying an area on short notice, and the data processed and up within just minutes of upload and stitching.

Right now Google's tools don't have any facility for looking at shots from an angle, while Microsoft's do but without the lovely interface of Keyhole/Google Earth. Angle shots can do things like see under some trees, which could be important. This would be a great public service for some company to do, and might actually make searches far faster and cheaper. Indeed, in time, people who are lost might learn that, if they can't flash a mirror at a searchplane, they should find a spot with a view of the sky and build some sort of artificial glyph on the ground. If there were a standard glyph, algorithms could even be written to search for it in pictures. With high-res aerial photography the glyph need not be super large.

Update: It's also noted the Kims had a cell phone, and were found because their phone briefly synced with a remote tower. They could have been found immediately if rescue crews had a small mini-cell base station (for all cell technologies) that could be mounted in a regular airplane and flown over the area. People might even know to turn on their cell phone if they are conserving power if they heard a plane. (In a car with a car charger, you can leave the phone on.) As soon as the plane gets within a few miles (range is very good for sky-based antenna) you could just call and ask "where are you?" or, in the sad case where they can't answer, find it with signal strength or direction finding. There are plans to build cell stations to be flown over disaster areas, but this would be just a simple unit able to handle just one call. It could be a good application for software radio, which is able to receive on all bands at once with simple equipment, at a high cost in power. No problem on a plane.

Speaking of rescue, I should describe one of my father's inventions from the 70s. He designed a very simple "sight" to be placed on a mirror. First you got a mirror (or piece of foil) and punched a hole in it you could look through. In his fancy version, he had a tube connected to the mirror with wires, but it could be handheld. The tube itself had a smaller exit hole (like a washer glued to the end of a toilet paper cardboard tube.)

Anyway, you could look through the hole in your mirror, sight the searchplane through the washer in the cardboard tube and adust the mirror so the back of the washer is illumnated by the sunlight from the mirror. Thus you could be sure you were flashing sunlight at the plane on a regular basis. He tried to sell military on putting a folded mirror and sighting tube in soldier's rescue kits. You could probably do something with your finger in a pinch though, just put your finger next to the plane and move the mirror so your finger lights up. Kim didn't think of it, but taking one of the mirrors off his car would have been a good idea as he left on his trek.


Damn, that's a really good idea.

With the APIs from Google Maps and Microsoft Virtual Earth, this would actually be pretty easy to implement. The annotations could be added without too much additional trouble; a wiki could also be added to organize notes about the search.

About the only hard part is acquiring the imagery, in terms of tasking the aerial photos. Once they were taken (and assuming they're digital), stitching them together and converting them into tiles suitable for GMaps/VE is pretty straightforward. There are plenty of tools out there to automate this aspect pretty well.

Any ideas on getting this part organized? If someone can figure that bit out, I'd be willing to make the UI.

Signal mirrors like this one and this one are common in aviation survival kits. They can be very effectively aimed without any of the tube-shaped add-ons that you're describing. They can be seen from dozens of miles away. While flying search and rescue missions, my own ground teams have used these to signal their location to me, and it's hard to miss, even if you aren't looking for it.

I think your proposal is interesting, but it's going to be a lot more effective to find cars and car-sized objects, than to find individuals.

It's very difficult to find individuals on the ground when you're searching by air, by the way, unless they're very aggressively trying to be visible (by using a signal mirror, for example). You just can't reliably spot something human-sized from the air, because of the speeds and distances involved. You're moving at a minimum of 75 mph or so (even in a helicopter; they can go slower or even hover, but that takes a lot of power, and burns fuel at a truly amazing rate), and are typically at least 1/4 mile or so away from the target (probably more).

Something car-sized is about the smallest thing that an air search crew can fairly reliably spot during an air search. Even that depends on a variety of factors, though; a silver car, against a snowy backdrop, partially obscured by trees, is going to be a real challenge to spot from the air.

I'm not sure what the resolution would be for the aerial or satellite photos that you're contemplating, whether they'd be sharp enough to make out an individual. Finding a missing car (or, in the case of a missing aircraft search, the crash site) is very useful, though, and can get you a lot closer to finding the individuals you're actually seeking.

I does the aimer on the "holographic dot" mirror work?

Anyway, this does indeed all depend on resolution. But high-res photography is getting much cheaper, and will continue to get cheaper as time goes on. I'm presuming we get down to one pixel per inch or so letting you spot people, clothes, some tracks, and of course cars. Plus any symbol (like SOS) marked out with rocks or tracks or branches or whatever.

My plan to design a glyph would work well if we could get people to know the glyph. To do this, I would gather lots of existing aerial photos, and then try test glyphs until you find one that does not occur in any of those photos (ie. not in nature or by accident.) It would need to be the simplest glyph that's easy for a computer to spot but not likely to occur in nature.

However, I think the cell phone proposal is the best one, and I will be expanding on it.

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