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Chemical "Infofuses" Communicate Without Electricity
Al writes "Researchers at Harvard and Tufts University have developed a way to send coded messages without using electricity. David Walt, professor of chemistry at Tufts, and Harvard's George Whitesides have developed 'infofuses' that can transmit information simply by burning. The fuses — metallic salts depositing on a nitrocellulose strand — emit pulses of infrared and visible light of different colors whose sequence encodes information. They were developed in response to a call from the Defense Advanced Research Projects Agency for technologies to allow soldiers stranded without a power source to communicate. In the first demonstration of the idea, they used the infofuses to transmit the message look mom no electricity." Currently the researchers are "trying to figure out a way to dynamically encode a message on the fly in the field without specialized equipment."
Smoke signals... in color.
Morse code... without electricity.
In order to communicate effectively without electricity, it makes sense to look back to the time before electricity.
As for coding-messages-on-the-fly for the flare o' many colors, what kind of data density are they looking for? Wafers of colored fuel could be dropped into a tube that is then sealed for burning.
Or, they could just figure out a way to send morse code with a flare... maybe some kind of retractable hood to be used as an interrupt?
"Trolls they were, but filled with the evil will of their master: a fell race..." -- J.R.R. Tolkien on Olog-hai
DARPA researchers discover messages can be transmitted using nothing more than a simple mirror.
One if by land, two if by sea
"Love heals scars love left." -- Henry Rollins
cause, you know...sending smoke signals when stranded in enemy territory is really going to help you....
"Our goal each year should be to increase the number of goals we set for ourselves!"
Step 1, smoke a cigarette under a poncho. Step 2, light an "infofuse". Step 3, get shot in the face.
My Drill Sargent demonstrated how easy it is to spot someone smoking in the dark.
Is a crank-powered radio really out of the question? I mean, it would even work during the day.
-Peter
in the end, why would a hand cranked flashlight not be better. maybe one of the shake up ones.
Some drink at the fountain of knowledge. Others just gargle.
How about an inexpensive crank flashlight with a morse code key engraved on it?
On the upside, not only would you not need matches, but you could use it as a flashlight.
I Am My Own Worst Enemy
DARPA keeps reinventing the wheel. Isn't it simpler to use a portable hand cranked generator to power a normal radio using spread spectrum communications? Using spread spectrum gives reasonable safety level and hand cranked generator is power source which works as long as you have hands. This solution is so obvious, that it amazes me why DARPA would even think of something else.
So it only transmits 2 km, and presumably someone has to be looking in the right direction to receive your signal, and you need some kind of special equipment to encode a long message. This just looks like the wrong approach. It seems to me there's always a trade-off between distance, information transmitted, and signal power (a rough restating of Shannon/Hartley). I don't know how far flares can be seen, but that's already a chemical means of sending a short message a limited distance.
One thing that might be interesting, the ability to produce a powerful radio signal by some chemical means. You wouldn't be able to transmit much information beyond say "help!", but if you had a satellite in geo-stationary orbit looking for these signals (and somehow triangulating the position) that might solve the "has to be someone looking" problem. Whether there are chemical reactions that produce radio signals, I have no idea.
AccountKiller
Said message could be sent with a single flash, if that's the only message they might send. The question is how many other possible messages they could have sent. For example, if they sent this as 7-bit ASCII, it'd be more impressive, though some kind of Huffman encoding would be most appropriate.
It's not much more than a new version of signal mirrors, heliograph, signal fires, etc. Even a minor power source (such as a hand operated generator) would allow a radio to outperform infofuses.
The only reason I see for this item, is when you are someplace electricity doesn't work. Of course, then the sensor package used to read the infofuse signal would need power also, and be within 1.5km/0.9 miles. Guess it's not really that good in an EMP field.
Of course, what about the gear to encode the message?
They are trying to make it simpler and smaller, but it doesn't sound like it's going to be an easy piece of gear to run without electricity. Of course, the troops could be sent out with a packet of pre-recorded messages. Or maybe just extra batteries for their radios...
Maybe I'm being a little hypercritical, but it seems as if they are trying to solve a non-existent problem with an overcomplicated solution.
(Kind of like trying to move the 15' from your parking space to the mailbox when you don't have your car keys but think you can hotwire the car with a screwdriver... Just walk over there stupid!)
Here's another idea, give the troopies binoculars and semaphore flags. Of course they'd then have to be trained in semaphore, but it's technology that's available and works without electricity, even after your choice of nuclear apocalypse or alien invasion.
Which would you rather add to your pack? A pound of flammable material, or a half-pound radio/battery with a half-pound hand-cranked generator?
Maybe I'm feeding the trolls but perhaps the key is that it's not a giant flag telling the enemy where you are down behind enemy lines. Maybe the fact that it's IR and can be activated when you hear your rescue run coming could have something to do with the fact that DARPA finds value in it.
Reading between the lines of the article it's apparently something that can be read by a remote sensor which means if you can attach that to a computer you make it perhaps even more useful in a rescue scenario where a small light rather than a big fire or flag is used to signal in the cavalry or air cavalry as the case may be.
Using existing technologies in existing ways is not research. Using new technologies in existing ways is. I'm a big supporter of research for the sake of research and science for the sake of science. Would you really have wanted DARPA to cancel the arpnet, because the application they had in mind assumed the use of nuclear weapons?
Note: I think that may or may not be the case that the arpnet was sold as a means for communications to survive in the event of a nuclear strike. but anyway you get the point I'm trying to make. Sometimes the craziest, least practical seeming research results in the coolest stuff.
Well.. maybe. Or Maybe not. But Definitely not sort of.
You only need to have one preset message:
"Enemy advancing on current position."
"There is more worth loving than we have strength to love." - Brian Jay Stanley
I think that's kinda the point - that it's something that would be hard to detect compared to traditional radio, for the same reason that laser speed traps are harder to detect than radar speed traps. This would be a very brief flash, presumably fairly directional, that would only be detectable by someone who was explicitly looking for it.
Rampant carbon sequestration destroyed the Dinosaurs' tropical paradise. I'm here to help repair the damage.