is there a photo of this invisible tank
(coat, obv)
Boffins have come up with a way to throw up an invisibility cloak, using a bunch of small antennas to create a force field instead of using metamaterials* to build a Harry Potter-style garment. A US Army M1A1 Abrams tank heads out on a mission from Forward Operating Base MacKenzie in Iraq on October 27, 2004 Tall order ... …
'The technology involved in making something properly invisible is so mind-bogglingly complex that 999,999,999 times out of a billion it's simpler just to take the thing away and do without it....... The "Somebody Else's Problem field" is much simpler, more effective, and "can be run for over a hundred years on a single torch battery."'
http://en.wikipedia.org/wiki/Somebody_Else's_Problem
I really don't think it would be good to use when cloaking a tank.
It only cloaks it to radar.
Thermal imaging and regular sight will still show the tank.
Now if you could integrate this in to an aircraft's skin and it would stand up to supersonic flight? ....
Or on the other end of the spectrum.... a slow moving airship.... at a high enough altitude w camouflage paint would make a good spy platform, especially at night.
The boffins also think that retuning the system to work with light waves, rendering the object truly invisible, should work on the same principles.
...
Downward pointing aircraft radars were set to highlight missing pieces of ground. Tanks using this kit would really draw attention to themselves.
Quite right. If I understand correctly, the device essentially turns the object black, not invisibile, as it prevents a given frequency from being reflected back. Nowhere in the article does it even imply that light from the oposite side is shuttled through. For a tank, I would think the bulk of a metamaterial-based shield would not be much of a problem. Taken together, though, radar-defeating and human-eye-invisible tanks (or war ships) would be a bit more scary, especially if they could decloak at will for intimidation purposes.
I just love the way that the boffin claims that a light-based cloak is basically the same principle as this radio-based one. I guess he's fishing for funding, or something, 'cos I can think of a couple of significant issues.
And surely this is no more than one level more complex than the radar jamming carried out by standard ECM pods since at least the 1960's ?
Sorry, but you were really asking for it.
This isn't really invisibility because whilst it may cancel reflections it doesn't substitute a replacement image. To use the Harry Potter analogy, when he put it on you'd see a pitch-black silhouette instead of what's behind him. As far as radar goes, well, it would probably be ok for above-the-horizon targets because you wouldn't get a return from the sky anyway, so the 'hole' wouldn't be apparent, but for targets below the horizon, where a discriminator is needed to pick the target out from the background returns then that 'hole' might be noticable, at least at relatively short ranges.
Re. "bypass[ing] obstacles" yes, it could certainly act as a repeater in the radio spectrum, and by messing about with phasing it could make itself appear to be bigger or smaller, or in a different place, but then that's not making it invisbile.
As for making it work in the visible spectrum? Well, I think they've got their work cut out there. With enough processing power you could make it work for _one_ point of view, but not for many points of view because the system would need to simultaneously project different backgrounds, not only for different directions but also for different perspectives, which isn't simply a processing issue; each single (re)emitter in the array would simultaneously need to send different signals corresponding to all the possible viewing positions. For example, if we imagine we're using an array of LEDs to display a visible spectrum replacement image then each individual LED would need to appear to be a different colour and brightness depending upon where it's being viewed from.
I'm not familiar with the term.. but why does every article in the Register related to science (that I've seen) refer to the researchers as 'boffins'? Is this term not both demeaning to the researchers as well as the authors.. who sound like they are admitting a failure to grasp a basic understanding of technology? From a quick web search.. the definition of boffin is:
"Boffin was a common colloquial term used in Britain during WW2 for the technical experts, the backroom boys, who were helping to win the war. An affectionate term, but with some practical fighting man’s scorn for the academic brain worker."
"why does every article in the Register related to science (that I've seen) refer to the researchers as 'boffins'"
Because that's our style. And rather than quote some random thing off the internet, let's look at the actual dictionary (OED):
"a person engaged in scientific or technical research: a person with knowledge or a skill considered to be complex or arcane".
That's it. No scorn. It is a term of endearment :-)
C.
Here's today's report card. The Reg just reported on a piece of pure grant-bait, PR designed to secure additional funding, or sources of funding, for the research group. (I'm sure DARPA will be knocking on this team's door pretty soon.)
Apart from anything else, the headline "Now boffins drape TANKS in INVISIBILITY CLOAK" is a weak cousin of the truth, "they draped a much smaller object in a field that does not cover the mainline case of visible light." Even allowing for the humorous tabloidese of the Reg it seems apparent:
You got played, suckaz.
Besides, last I checked, radar tech is starting to move to multistatic installations, which can work more passively (meaning destroying the transmitter doesn't necessarily degrade the efficiency of the receivers) and actually turns current stealth tech against itself (because they normally work by deflecting radio waves--such craft would stick out like a sore thumb in a multistatic radar reading because they'll be blocking expected signals).
Not if they were expecting a hole, the sky for instance, and if you can destructively interfere with the incoming radar and cancel it out then presumably you could adjust that interference to appear to be something other than a tank, like a bus, perhaps if you had access to a sample of the radar stations sweep you might even alter the reflection to recreate what would have bounced back if your tank wasn't there.
Probably-- and quite rightly-- my generation-old "knowledge" will be jumped like a June bug by hens...but...sincerely...can anyone tell me how this is "something new under the sun"? Is this not decades-old aviation Electronic Counter Measures? Put another way, how is this not, "Move along, move along, nothing to see here"?
My neighbour used the "SHGIC" field to pass the financial controllers gaze.
He'd drop off the new boxes and bits at my house and sprinkle some dust and fingerprints over the main device then leave it on the passenger seat of his car until later. That evening he would remember to bring in the SecondHandGotItCheap device from the car to see if he could fix it in his shed.
He had a high success rate getting that stuff going.
I guess the scam worked for a while.
Can't remember where he is buried.
And what about spread-spectrum radars that vary their frequency rapidly, in a pseudo-random basis? How will they cancel that out?
Of course, the problem with visible light is orders of magnitude harder. There you have an infinite range of frequencies simultaneously impinging on your device, coming from every angle at once.
Has anyone looked at animal rights issues concerned with covering tanks with hundreds and hundreds of invisible kittens, and the usage of said kittens in a live combat environment?
Yes, the kittens may make the tank invisible. However, I don't think enough research has been carried out into the difference in protective capabilities between invisible kittens and other forms of ablative armour.