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Cloak of Invisibility Coming Soon?
Chris writes "The idea of an "invisibility cloak" has made the leap from science fiction books to an international patent application. The "three dimensional cloaking process and apparatus" for concealing objects and people (WO 02/067196) employs photodetectors on the rear surface which are used to record the intensity and color of a source of illumination behind the object. Light emitters on the front surface then generate light beams that exactly mimic the same measured intensity, color and trajectory. The result is that an observer looking at the front of the object appears to see straight through it."
...what's the bonus to saving throws when wearing it? :)
--Kylus
Idiot-proof something, and Life will build a better Idiot.
There are many angles crossing an object, although this may work for simple front to back (as the article states)
I don't think it is that workable for all directions, or even more then a few.
The problem with this device as it's designed so far is that it only works when looking straight at the object.
In addition, I have serious questions about the resolution of the device (how many sensors and how many light emitters). Will the person look "pixelated" and or will there be some other problem.
Lastly, such a device is not useful in combat situations as many soldiers in such a ground war situation will be outfitted with infr-red detectors, which will probably be able to detect the human behind the suit.
Good idea but has a lot of practical problems (we haven't even discussed the power source).
I suspect that the squeaking of the wheelbarrow that you'll need to carry the batteries, fuel cells or magic moonbeams that'll be needed to power this thing will render any invisibility firly useless.
But I still want one, go figure
Get the EULA T-shirt
I'll be more impressed when a Cloak of Charisma is released; hellloooo, laydeez|boyz!
(and no, those new cargo pants you just bought from Gap do not count).
----- Documentation is worth it just to be able to answer all your mail with 'RTFM' - Alan Cox.
Most readers of Slashdot already have one of these. Problem is, it only works on women.
The only problem is, you're going to see some weird shadowing around the cloaked object and be able to tell that it's there. I can't believe that I'm actually replying to this post.
Naked Woman: Actually, I can see a shimmery shape, because you're slightly off-center to me.
PWTHI: Wait, wait, you're not in the right place. Move to the left.
NW: Ok. Now you're even MORE shimmery
PWTHI: No, no, MY left, not your left
NW: Oh, sorry. There, the shimmering went away.
PWTHI: Ha ha ha ha!!!! I can see you naked!!
NW: Sir, this is a strip club. It's not exactly difficult.
Instead of making me invisible, I just want it to make me look thinner. Shave off my side edges by painting the background over my sides, and voila, I've lost 20 pounds.
What's your damage, Heather?
This has been done before using fibre optics, I believe, so that you would effectively see through the person because they wore an outfit consisting of thin fibre optic wires routeing light straight through them. This was on TV once, although I don't know whether it was the actual suit being shown or merely some special effects to show what it _could_ look like. Either way, it looked obvious that there was someone there - anything longer than a brief glance would be time enough to tell.
Like car accidents, most hardware problems are due to driver error.
...Metal Gear Solid! Honestly, I think the bandana would be more fun to have, but I'd settle for invisibility, even if a cardboard box works most of the time.
I believe in WWII some submarine hunter aircraft had spotlights on the front to make the apparent brightness of the dark aircraft match the sky. Killed more subs that way.
this technique worked really well for large objects if they were a good distance away, like for a tank of the horizon or an aircraft in the sky. awful for close up work.
I recall a good article on this someplace on the web, but to find it now on short notice .....
"It is a greater offense to steal men's labor, than their clothes"
Can't the fact that the idea has been around for a long time, in both sci-fi books, movie and games mean this has "prior art".
Uh, no. I am not a patent lawyer, but I believe prior art means someone actually has to have built such a thing, not just dreamed it up.
What, no pictures?
It's 10 PM. Do you know if you're un-American?
Whew!... just imagine if this technology had been developed before our ability to uncloak terrorist networks.
The evaluation of an action as 'practical' . . . depends on what it is that one wishes to practice.
I can see this happening, with a lot more refinement. You'd need gobs of processing power, hosts of tiny photodetectors and projectors, and a very small but reliable and long-lasting power supply (as somebody else already noted). With today's tech, this idea is pretty useless. The engineering obstacles could be overcome in the future. On the other hand, it would be pretty easy to come up with effective countermeasures. Wouldn't this thing radiate like hell in the infrared?
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For looking straight at the object: just coat the whole thing in emitters and detectors. That's not a big fundamental problem. You don't want light reflecting off the object anyway; might as well have detectors that absorb it.
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The resolution problem can be addressed simply by increasing the resolution until it's small enough not to be noticable. Regardless, even at low resolution, it's better than normal camouflage, isn't it? (Ever seen Predator?)
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The infrared problem can be solved the same way the visible light problem is solved. Just have IR detectors and emitters. You can even to a variety of frequencies (just as with visible light) to fool various enemy equipment.
To me, a big problem would be to counter an active detection system that shines light on the object and looks for reflections. The emitters will be subject to a design trade-off between emission and absorption, and it might be hard to find a technology that does both well enough.Patrick Doyle
I mod down every jackass who puts his moderation policy in his sig. Oh, wait a sec....
My completely uneducated guess is that the object will appear a lot like those "magic eyes" pictures that were all the rage a few years ago...
i.e. when you move from side to side (or up/down) the object will shift at a slightly different rate than the background, and your senses will detect something. you may not be able to tell what it is, but something will feel "off". I'm sure at greater distances the effect will be less, and therefore the technique will be more useful.
Reminds me of Predator, and the way that it shimmered when it moved. My guess is that they used the same thought when they made that movie.
Very cool.
No man is an island, but Gary is a city in Indiana.
I don't think it is that workable for all directions, or even more then a few.
Not only that, but you'd have to look at it from a pre-determined distance in order for the rendered view-angle to be appropriate.
The article very definately uses the words "detect" (light behind) and "generate" (image in front). This implies it is not some passthrough technology (fiber, etc), but an electronic record and recreation.
If this "clock" could live up to its claims, there are three (possibly more) far more interesting applications that must be considered:
Given that researchers would be coining it from more down-to-earth inventions like these, I can't really see that the technology - as described - exists or is being developed.
i-name =twylite [http://public.xdi.org/=twylite], see idcommons.net
I always thought one of the coolest gadgets mentioned in Sci-Fi was the 'reactor' for the personal shield generator in the Foundation Trilogy.
It was the size of a walnut. Of course, it didn't last very long, but a walnut-sized reactor would still be pretty cool (albeit very unlikely.)
The opposite of progress is congress
The most important part of camoflage is making recognizable features hard to see -- hands, faces, etc -- things our visual system is hardwired to pickup out of the background. This invisibility cloak would do that.
I imagine it looking like the Alien in that Arnold movie, hard to see unless it's moving and then the distortions give it away.
Of course is this a really old idea -- heck it a similiar idea was in comics in the 1970s (some super heros club house had this kind of device to hide it from view).
I was hoping to see the cloak in action. :-)
If something is so important that you feel the need to post it on the internet... It probably isn't that important.
Now, if there were a work of sci-fi that described how to implement this device in detail, then that might be prior art.
Patrick Doyle
I mod down every jackass who puts his moderation policy in his sig. Oh, wait a sec....
Again, IANAL, but I don't think it needs to have been built, just described accurately enough that it's not a new insight for the person actually building it
IIRC nobody could patent geostationary satellites when they were first built because a certain well known sci-fi author had described the concepts previously.
Or I could be talking crap, that happens too.
...when I see it.
Sorry, it had to be said.
This is a pretty near perfect example of a bad patent.
1) the idea is pretty obvious (as well as many references in common SF literature)
2) the actual implementation with current tech will be pretty miserable. Put big bright light behind object, make object shine big bright light at viewer. Viewer is blinded by both and as object is indistinquishable the technique is easily demonstrated to the patent requirement level.
3) it serves as a patent stake. Further research into a better/improved technology will have to deal with this patent.
This is a near perfect bad patent that grants the patent holder a big stake in the ground for actually showing very little. And any future work that will actually improve the technique is going to have to deal with the patent.
This is interesting, but will be of rather limited usefulness if the viewable angle is not very wide.
You see? You see? Your stupid minds! Stupid! Stupid!
Even if this intended to be just one way. You'd have to have very little light coming from the direction of the intended person to be "blinded." This would assume that this cloak will absorb *all* (up to a point that's observable) the light that would have reflected off of it and to the observer. Well, perfect black body's just don't exist. There'll always be likely to have a reflection come off of this thing.
/me wanders away.
That's just the beginning, I don't think we're anywhere near having what's essentially an instantly recorded and rebroadcast super high resolution wrappable screen. The way, though I could be mistaken, that most light sources are created even in high definition display devices, will allow for scattering, so the image you would see where the person should be would be blurry. You'd have to get pretty close to duplicating every photon. Not nearly so accurately of course since the human eye isn't so good, but still.
Anyway, I'm just stupid.
Many have already pointed out the most obvious problem -- any angle other than straight on is going to wreck the effect. But let's not forget that a human with two functional, open eyes never views an object from just one angle (unless one eye's view of the object is obstructed -- geez, picky...). Ah, the miracle of depth perception. I don't think this method is nearly sophisticated enough to compensate for all the subtle clues we get from our binocular vision. Nice try, though. I mean, I think that everyone who's considered the possibility of invisibility has come up with a scheme like this. It's nice to see it coming closer to reality, but we all know that at this stage it's too limited except for perhaps certain special circumstances. But yeah, I want one too.
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It also doesn't do much for your heat signiture. Since so much military surveillance is done with IR, you'd think that the extra heat generated by the thing being cloacked and the cloaking mechanism that it'd glow like a light bulb under IR.
I mean, its not as high tech, but its a lot cheaper.
"...not just dreamed it up."
:)
Isn't that what a patent is, just an idea that has been "dreamed up"?
"The idea of an "invisibility cloak" has made the leap from science fiction books to an international patent application.
<sarcasm>
That's supposed to be a leap? Somebody hasn't been keeping up with patents lately....
</sarcasm>
Ever since I read William Gibson's "Neuromancer" for the first time, invisibility has always been synonymous with the Panthers Modern's mimetic polycarbon suits. The graphic novel only served to burn this image into my mind even more by giving form to how it would look / work / be used.
Too cool. They should hand these out to Delta Force and snipers once they've been refined a few times over. Then they'll really be something to be afraid of -- living, heavily armed ghosts.
The Mona Lisa blocks light on the wall behind it. You'd see a black patch on the wall, because there'd be no light. To get this to work, you'd have to mimic light going in both directions, so that the lights in the room would "pass through" the cloak and hit the wall behind it, then bounce off and "pass through" the cloak again.
Last post!
I look at this and I can't help but think of the ol' Cloak of Darkness out of Wizards & Warriors.
Thou hath wasted thy fucking time
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It doesn't have much, but there is a pretty picture!
-jbn
...they'll also discover the cure for "Quicksilver Madness" before this goes operational.
Shadowrun mentions this, in some detail. IIRC, it involves a lattice of fiber that redirects light around you.
And it doesn't have to be in detail - Heinlein patented the waterbag. Okay, bad example - trivial to implement, tough to invent.
"Sometimes a woman is a kind of religion, she can save your soul & set you free from all your sins" - Bad Examples
-jbn
when someone else in the future figures out how to make a bona-fide cloaking device (complete with that awesome Romulan warbird cloaking sound), he'll charge them a licensing fee for their design because he already patented the basic idea.
In that case, it's called gambling. Patents last 20 years after filing in most jurisdictions because the late Sonny "Treehugger" Bono never managed to touch patents. Thus, Ray Alden is making a bet that a cloaking device will be developed within the next twenty years.
what if it's only, say, 10% functional? Not at all useful
Except for a well-done camouflage suit, where a little goes a long way.
Will I retire or break 10K?
I wonder how he intends to get round nthe fact that the back of a soldier is nothing like the front of a soldier and the clothing needs to be flexible and will change shape, so you can't just link sensors one to one. Unless the camoflauge outfit is shaped like a rigid barrel, you not only need to know what's behidn you, but you also need to know the exact shape and position of the "cloak". How is that done?
----------------------------------- My Other Sig Is Hilarious -----------------------------------
I made one of these before...
www.Beyond7.com Insane modern art water sculpture.
Would be to flood an area with high intensity light. The re-emitters will be strongly limited in how much light they can throw out, and what you would see would be a moving dark spot (still looking like the ground beneath him) against a light background.
If your bitterest enemies are people who hack the heads off civilians, then I would say you're doing something right.
...is an amusing century-old story about competitive brothers who devise two different methods of achieving invisibility. It's online here.
In his fictional story, both methods have problems. The problems are more than fictional, since one of the methods relies on the nonsense supposition that since black is the absence of light, the only reason you can see something that's black is that the black isn't PERFECTLY black, and that if you could achieve perfect blackness you could achieve invisibility.
However, the method described in the parent article here is equally flawed, since it would work only for an observer placed in a specific view location. One wonders how the equipment is supposed to locate the observer; if there are several observers, how does it decide which of them should be prevented from seeing the object?
The method bears a close resemblance to Hollywood special effects processes (glass shots, matte shots, etc.) Special effects processes are notorious for having visible edge effects if not done carefully, and I'm sure this would be true of the proposed method as well.
In "The Shadow and the Flash," one invisibility cloak could be detected by a sensation of darkness and depression whenever the concealed individual was nearby; the other suffered from occasional rainbow flashes due to mismatches in the index of refraction. I'm sure that the proposed method would have similar problems.
"How to Do Nothing," kids activities, back in print!
So basically its a very complicated method of using the old smoke and mirrors affect that magicians have employed for years?
So in fact you would be better off being in plain sight, looking like someone/thing normal and harmless.Since that can be done very cheaply and without fancy technology, I think it will remain the preferred method of infiltration.
Or use both: A delivery guy with a cardboard box and clipboard can walk past while guards surround the guy in the suspicious skin-tight chameleon suit.
-- What do you need?
-- Gnus. Lots of Gnus.
We won't be ahead of the Klingons until we can fire phasers while cloaked.
Only a patent
Haven't you been reading any other articles lately? Only a patent? You mean like Amazon's "one click" patent? Like BT's patent of hyperlinks? Compuserve GIFS? A laser pointer as an exercise device for a cat? The patent on a swing?
No, it's not a new idea. The military has been playing with it for years. Deep sea fish do it naturally with bioluminesence. If they get a working model, then ok, give them a patent. But I'd hate to see another ridiculous patent granted on an idea that's been around for decades.
-- If god wanted me to have a sig, he'd have given me a sense of humor.
How about a house with sensors on the outside walls, and the projectors on the inside?
It would be like being outside, except the outside couldn't see or get in. And I'm sure it probably wouldn't transmit uva/uvb, so no sunburn. Imagine, no more sky windows. The ceiling could be the sky, complete with clouds. (Of course you could control the briteness, turn it off/on, etc.)
This could even replace windows in buildings you'd want more secured or where glass is a structural liability.
I remember talking about invisibility with friends after seeing the original Predator film.
The concept of light readers on one side of an object and light emitters on the other was an idea that was quickly proposed (by me) and then rejected (by me and others) because (a) it's too much of a "brute force" technique and not particularly scientific, (b) the required resolution to be 100% effective would be so high as to make it practically impossible, (c) it wouldn't stand up to any reasonable human scrutiny, never mind computer analysis, and (d) it would only work with fixed-shape objects, not people or animals, because any change in shape of the enshrouded object would produce distortion in the 'invisibility'. (Presumably this was the logic behind the shimmering effect of the alien in Predator?)
So I hope this patent application isn't successful unless it is *solely* for the implementation, not the idea. If they're trying to patent the idea then I want to claim prior art by at least ten years, even if we didn't get past the discussion stage.
And if I ever try to patent the idea then I expect Jim and John Thomas to take their turn at claiming prior art, and they should win. And I'm sure there were others before them.
The hardest problem to solve is that one pixel would not have the same color depening on where you stand watching it.
when I was 6 years old, I thought that could be done by adding a bunch of mirrors to redirect light around the person wearing the cloak. Kind of like a lot of periscopes or fibre optics. There are lots of problems with this idea, namely the bulkiness of the mirrors and such, but I was 6 when I thought of it.
I guess this is my declaration of my idea. Fee free to reference this as prior art when someone tries to patent an invisibility cloack through the use of mirrors.
If someone can patent something that I thought of when I was 6, then either (a) something is wrong with the patent office, or (b) I should be filing a lot more patents.
The significant problems we face cannot be solved by the same level of thinking that created them. -Einstein
Photo reception on one end. Light emission on the other.
Was this not obvious to anyone a decade ago?
No Zen is good zen
...a productivity cloak.
Imagine it. You're having a lousy day at the office. Got nothing done, but read email. Your boss comes storming in asking for a report that's 2 months overdue. You simply throw on your productivity cloak and (walla!) your screen shows a nearly completed report, while you appear confident it'll be done soon.
managers...why god invented purgatory
The article explains that the photoreceptors and emitter array would copy what's behind the wielder and blast it forward. Great, but what if the object behind you is super luminous or moving very rapidly. I doubt the photoemitters could keep up with, say, the sun. Heck, they might not even be able to render Quake 3 at a decent frame rate. Not to mention the power requirements...(read any of the the "wheelbarrel" comments made by others.) Also, this idea has been thought up before. Prior Art being a concern, I (personally) would reject his patent claim.
In my version fiber optic was carefully woven so that each strands start point was directly opposite it's exit point on all sides of the object.
The device they've generated uses a similar approach but probably works much better because instead of using a passive fiber optic system, it replicates the light. Probably much easier to build and walk in - though undoubtly hotter and power hungry.
If you think about what something like this would look like... it would resemble the alien from the movie Predator. Why? Because of refraction issues. Specifically - in the fabric you will be bringing the light that is behind you, to in front of you, while the light that is flowing around you will pass through more air. The result will be that the refractive index of the reproduced light will be missing about 5 inches of air, thus it will shimmer slightly like a heat wave.
I actually came up with 3 methods of invisibility... here they are:
1) Fiber optic suit, just described.
2) This one is great for holloween... get a tiny tiny color digital camera on a chip, a jean jacket, and a tiny LCD color TV. Put a hole through the back of the jean jacket and mount the camera inside so that it sees out the back of your jacket. Mount the LCD panel on the front of the jacket, preferable behind a similar sized hole you cut in the material so that it hides all but the LCD screen itself... turn it on, and it should look like you have a Terminator 2 style bullet hole going right through your body.
3) Drugs :) In the 60's thorough 80's wonderful experiments were done to determine how the eye sees. Our eyes see by constantly twiching very very quickly. The twitch causes the cells in our eyes to move in and out of what they are looking at. Cells that are looking at edges with contract will thus cycle in and out of contrast and trigger - so we see the edges. Researches took two approaches... first, they placed a red square on a white card and using photosensors, watched the twich of the eyes and moved the red square in sequence with the twitches. This means that the eye could not see the edges since it kept them in the same position with the twitch... the result? The red square immediatly became invisible (the user only saw white) because of over saturation of the cells and no edge visible. The second method was to induce a drug that caused the rapid movement of the eyes to be suppressed... once administered - as long as the head is still your basically blind. An interesting theory on cats (though I don't believe proven yet) is that they don't have the natural twitch and use this for hunting. Sitting very still, anything that moves is instantly very very visible while the rest is virtually invisible. Additional speculation is that purring is a natural mechanism for producing a twitch in the animal as well.
Whatever... invisibility is fun ;))
More likely, they were just thinking that a truly invisible creature didn't make for very scary film footage.
He looked at me and said, "Kid, we don't like your kind, and we're gonna send your fingerprints off to Washington."
Now that they have solved the tall guy sitting in front of you in the movie theater .... Now they just need to solve the jerk sitting behind you kicking your seat.
I've already got one of those on my digital camera.
It's neat, when I turn on the screen on the back, it's like the middle of the camera is invisible and I can see right through it!
Punctanym: alternate spelling of words using punctuation or numerals in place of some or all of its letters; see 'leet'
In his fictional story, both methods have problems. The problems are more than fictional, since one of the methods relies on the nonsense supposition that since black is the absence of light, the only reason you can see something that's black is that the black isn't PERFECTLY black, and that if you could achieve perfect blackness you could achieve invisibility.
And the other process was to make the subject transparent. Would work if possible but also impractical.
But a "cloak" that either records the view on one side, small patch by small patch, and reconstructs it on the other side ditto, or actually pipes the light around and re-emits it, has been used repeatedly in science fiction since the Golden Age of Campbell's editorship of Astounding/Analog magazine.
I THINK some of 'em even got the need for networking each "camera" to multiple "displays", to account for the virtual passage of light through the thickness of the cloaked space, though I don't recall any of 'em explicitly mentioning the need for the network connectivity to be dynamic, to account for a flexing body.
(I'd dig through my collection to find a few samples but it would take a while. If you want to dig through yours, start with Randall Garret.)
Now if somebody has come up with a particular WAY to pipe the light or its signal around that's worthy of a patent. But if they've just patented the idea of mimicing a transparency (light emission) or do what an octopus does (variable absorbtive color cells to mimic the surface behind), it's been described repeatedly.
An aside: One of the funnier throwaways in a fantasy novel (Too Many Magicians?) was the presentation at a magician's conference of a spell for making EVERYTHING BUT THE EYES invisible. The disadvantage of the previous spells was that they made the subject blind, because the light didn't interact with his eyes. It is easier to hide a floating pair of eyes than a whole body, and easier to be unnoticed if you aren't constantly bumping into things. B-)
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
As soon as someone wearing this walks in front of a painting or billboard or magazine rack...BAM!...you get them on copyright infrigement. No hope for you.
The idea I came up with a kid involved one way only invisibility using about 40 million of those little fiberoptic tubes you can get, and bending then around your body so that one end pointed behind you, and the other pointed in front of you. So people would just look right through you. It didn't work as a 'I'm walking through this crowd of people and they can't see me' invisibility, but it seemed like it would work great if you didn't move much (A sniper or something).
Kintanon
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In my days as a tanker, I basically stopped using optical sights altogether. Thermal imaging is so much better it's scary- you really can see in the dark, through camo, etc. Even in fog/rain it's still better than optical.
"Seven Deadly Sins? I thought it was a to-do list!"
Aren't you all so lucky, no only do you get to hear my opinion (as if you cared) bu tI get to pull out a related anime quote for extra karma points. Anyways...
While it may not be perfect now, the idea and (if it exists) the current prototype are enough to generate interest and development. To use a computer related example, when Xerox developed the GUI at PARC, it was far from perfect. If the type of cynicism with which we look at things today existed then, the GUI might never have been developed any further. But someone (notably some Apple employees) saw potential and said that it could be developed and improved. And they were right.
Now for my anime quote - from Ghost in the Shell:
"If man realizes technology is within reach he achives it, like it's damn near instictive."
T Money
World Domination with a plastic spoon since 1984
yup, a simple space blanket (you know, the little silver colored emergency blankets) makes a great thermal cloak.
1 Stops almost all radiated heat.
2 Obviously there is no convection if you are wrapped in a blanket.
3 And conduction isnt much of a factor for thermo-imaging.
\
Had a similar idea, believe it or not. I was thinking about this kind of thing when to cloak aeroplanes... just never knew how it should work. Hopefully someone figured it out now.
Will work for bandwidth
Interestingly enough, I predicted essentially this same technique during an earlier discussion on the nanotechnology nanotechnology defense initiative at MIT.
/. ;-)
A key example of how life imitates
Bob
Science, like Nature, must also be tamed, with a view turned towards its preservation.
An invisible hologram? How pointless is that?
skkkoooonnnggggkkk ptui
I completely foiled my pursuer. (Who obviously was an idiot, but I digress.)
"I can't give you a brain, so I'll give you a diploma" - The Great Oz (blatently stolen sig)
To be truly effective, wouldn't all the emitters have to be pointed directly at the observer, and all the detectors pointed exactly in the opposite direction? I don't think "cloak" is the right word for this; it obviously needs to be fixed, not flexible. Also, isn't there a lot of "prior art" on this in old SciFi stories?
"Freedom means freedom for everybody" -- Dick Cheney
FWIW, The Bourne Identity (the book, not the movie), was 90% about exactly this kind of social engineering. The rest was mostly love story, mixed with occasional gunplay.
Any sufficiently well-organized community is indistinguishable from Government.
from the article
The light emitters on the front surface then generate light beams that exactly mimic the same measured intensity, color and trajectory.
So, the difference between this and what most people here seem to be talking about is that the light beams would come out in the right direction, meaning that you don't have to look at it straight on. You still might have perspective problems if you get close, but those will fade with distance.
Now, if he can develop technology to detect, process, and appropriately reconstruct all the rays which would pass through an object were it invisible (basically a badass image based rendering system and really really bad ass display) then he probably deserves a pattent.
A point on detection technology, though: if this is designed to hide from humans, it will only produce output colors from mixes of red, green, and blue. If you make a camera which sees in more colors (prev discussion on IR), it could detect the cloak. The cloak's emitters must be as advanced as the sensors it wants to avoid.
If programs would be read like poetry, most programmers would be Vogons.
Unfortunately, tanks and B2 bombers really have trouble looking like "something normal and harmless". For that matter, so do platoons of soldiers with M-16s.
Unfortunately for whom? What you say is right, but I was only discussing infiltration.
Anyway, tanks and bombers are last century's way of getting what you want. Some dickheads haven't realised that yet *cough*dubya*cough*.
-- What do you need?
-- Gnus. Lots of Gnus.