• Hi Guest! Forum rules have been updated. All users please read here.

Can Scientists Make a Tank Invisible

bobbymike

ACCESS: USAP
Joined
Apr 21, 2009
Messages
10,412
Reaction score
1,361
From Defensetechblog - http://www.defensetech.org/archives/004987.html#comments
 

Simon666

ACCESS: Confidential
Joined
May 9, 2007
Messages
105
Reaction score
0
bobbymike said:
From Defensetechblog - http://www.defensetech.org/archives/004987.html#comments
As has been pointed out in the comment section, the answer is no. Cloaking only works in what is called "the near field", so only objects smaller than (at most a few multiples of) the wavelength of the radiation involved can be cloaked. For light, that would mean at most a few microns. Passive cloaking is further limited to one wavelength and some harmonics, active cloaking can do somewhat better but is still just theory.
 

PNorwood

ACCESS: Restricted
Joined
Aug 18, 2009
Messages
49
Reaction score
2
Here is a .pdf file which explains how it is done.
(The file is from the link which was posted by bobbymike)

http://www.opticsinfobase.org/DirectPDFAccess/CF124420-BDB9-137E-C46C9C4B3B4F444A_184385.pdf
 

Grey Havoc

The path not taken.
Senior Member
Joined
Oct 9, 2009
Messages
11,940
Reaction score
2,083
On a related note: http://gcaptain.com/invisibility-cloak-ships/?29425

While the cloak postulated by Urzhumov differs from other cloaks designed to make objects seem invisible to light and sound, it follows the same basic principles – the use of a man-made material that can alter the normal forces of nature in new ways.

In Urzhumov’s fluid flow cloak, he envisions the hull of a vessel covered with porous materials – analogous to a rigid sponge-like material – which would be riddled with holes and passages. Strategically placed within this material would be tiny pumps, which would have the ability to push the flowing water along at various forces.

May have some interesting naval applications apart from the obvious.
 

Dragon029

ACCESS: Top Secret
Joined
Mar 17, 2009
Messages
761
Reaction score
108
PNorwood said:
Here is a .pdf file which explains how it is done.
(The file is from the link which was posted by bobbymike)

http://www.opticsinfobase.org/DirectPDFAccess/CF124420-BDB9-137E-C46C9C4B3B4F444A_184385.pdf

I believe the idea behind using metamaterials to cloak large objects is to pass light around one microscopic structure, to another next to it and then continuing the process until it reaches the front of the vehicle, where it encounters another type of structure that diverts the light forward, like a daisy chain of bizarre physics.

Personally, the thing I always wonder about is that if they get the materials on and working, etc - how exactly will they protect them, seeing as such minute structures are quite susceptible to damage. If they're coated with some clear plastic, etc that will be visible. Additionally, I'm not sure what effects that would have on thermal visibility, as heat will obviously be conducted from the vehicle. That would be where things like that wolf-something IR stealth tech would be handy.
 

Gerard

ACCESS: Restricted
Joined
May 27, 2008
Messages
18
Reaction score
1
I don't have any problem with the idea that technology will be able to make a tank invisible.

That is, to human, tv FLR, thermal viewers. Radar too. When on a nice concrete parade ground.

I've got doubt abouts how it will manage in the Arctic, dessert, tropics, mud, dust, rain, crossing a river. Or when a few 152mm shells airburst 10 or 20 yards away.

Also, how do they get rid of the thermal exhaust, which might be seen by a satellite / UAV ? Heat sinks can only do so much ? And what about when the main gun fires ? though railguns may help there.


Regards,
Gerard
 

Lauge

ACCESS: Secret
Joined
Jan 30, 2008
Messages
434
Reaction score
7
Gerard said:
....though railguns may help there.

Not necessarily. Railguns, not being 100% effective, will produce copious amounts of waste heat that you need to get rid of somehow (further stressing those heatsinks you mentioned).

Also, for any railgun worth its salt, the projectile is likely to be followed out of the muzzle by a burst of plasma from the conductive sabot and the armature.

Regards & all,

Thomas L. Nielsen
Luxembourg
 

Dragon029

ACCESS: Top Secret
Joined
Mar 17, 2009
Messages
761
Reaction score
108
Gerard said:
I don't have any problem with the idea that technology will be able to make a tank invisible.

That is, to human, tv FLR, thermal viewers. Radar too. When on a nice concrete parade ground.

I've got doubt abouts how it will manage in the Arctic, dessert, tropics, mud, dust, rain, crossing a river. Or when a few 152mm shells airburst 10 or 20 yards away.

Also, how do they get rid of the thermal exhaust, which might be seen by a satellite / UAV ? Heat sinks can only do so much ? And what about when the main gun fires ? though railguns may help there.


Regards,
Gerard

Theoretically and assuming it works exactly as hoped (taking the light from behind it and bending it around the surface of the object, to in front of it), you should only see a shadow on the ground and possibly a few floating lenses. There wouldn't be any flickering, very little difference in contrast, brightness, etc, simply because it's not a digital or electronic system, simply a material that places a visual portal on the silhouette of an object, linking to another located 180 degrees around the object.

Of course, that is the ideal situation. How it's implemented will dictate how well it works. For example; they can't make materials that cover every possible convergence angle, so there won't be that many dissimilar angles on a tank. This would obviously be problematic, but it can be solved by placing a shell over the tank, covered in the material. However, that in turn alters the maneuverability of the tank as you would have a big turtle shell covering it. You could have it mechanically move to raise and tilt it over terrain (guided by radar or laser sensors), but that's adding more mechanical complication. Additionally, applying the molecular structures will likely be a very slow process unless some amazing assembly tool is developed.
 

Grey Havoc

The path not taken.
Senior Member
Joined
Oct 9, 2009
Messages
11,940
Reaction score
2,083
For infantry optical signature reduction, this might have some application.

"We are currently investigating another, milder candidate reagent which would allow us to study live tissue in the same way, at somewhat lower levels of transparency" he said. "This would open the door to experiments that have simply never been possible before."
 

Grey Havoc

The path not taken.
Senior Member
Joined
Oct 9, 2009
Messages
11,940
Reaction score
2,083
Apparently Hägglunds has revealed a CV90 equipped with a prototype of what could be described as an integrated thermal cloaking system. Complimentary systems for visual and radar cloaking are currently further back in development. (H/T to Micael over at HP&CA)




Bing translation:
http://www.microsofttranslator.com/BV.aspx?ref=IE8Activity&a=http%3A%2F%2Fwww.nyteknik.se%2Fnyheter%2Ffordon_motor%2Fbilar%2Farticle3246446.ece

Original Ny Teknik article:
http://www.nyteknik.se/nyheter/fordon_motor/bilar/article3246446.ece
 

robunos

You're Mad, You Are.....
Senior Member
Joined
May 1, 2007
Messages
1,921
Reaction score
267
Grey Havoc said:
Apparently Hägglunds has revealed a CV90 equipped with a prototype of what could be described as an integrated thermal cloaking system. Complimentary systems for visual and radar cloaking are currently further back in development. (H/T to Micael over at HP&CA)


Bing translation:
http://www.microsofttranslator.com/BV.aspx?ref=IE8Activity&a=http%3A%2F%2Fwww.nyteknik.se%2Fnyheter%2Ffordon_motor%2Fbilar%2Farticle3246446.ece

Original Ny Teknik article:
http://www.nyteknik.se/nyheter/fordon_motor/bilar/article3246446.ece
English version from Sky News...
http://news.sky.com/home/technology/article/16063257




cheers,
Robin.
 

pathology_doc

ACCESS: Top Secret
Joined
Jun 7, 2008
Messages
965
Reaction score
181
I suppose thermal cloaking could make the statistical difference between being hit by some sort of autonomous submunition or missed, or might mask your presence for long enough to get in a bit closer and be sure of killing what's looking for you, and that might be worthwhile; but having what the Klingons and Romulans have seems about as far off as the actual USS Enterprise and James T. Kirk IMO.
 

Grey Havoc

The path not taken.
Senior Member
Joined
Oct 9, 2009
Messages
11,940
Reaction score
2,083
Via MilitaryPhotos.net and DISCOVER magazine, here's the short BAE Systems video (which, of course, doesn't mention Hägglunds or the Swedish government's involvement):

http://www.youtube.com/watch?v=ZbxcVQsE_3g&feature=player_embedded
 

RLBH

ACCESS: Secret
Joined
May 5, 2007
Messages
346
Reaction score
184
Grey Havoc said:
Via MilitaryPhotos.net and DISCOVER magazine, here's the short BAE Systems video (which, of course, doesn't mention Hägglunds)
You mean BAE Systems Hägglunds AB?
 

Grey Havoc

The path not taken.
Senior Member
Joined
Oct 9, 2009
Messages
11,940
Reaction score
2,083
RLBH said:
Grey Havoc said:
Via MilitaryPhotos.net and DISCOVER magazine, here's the short BAE Systems video (which, of course, doesn't mention Hägglunds)
You mean BAE Systems Hägglunds AB?

BAE Systems appear to be currently trying to get rid of the Hägglunds identity, some reports are suggesting they're stripping Hägglunds for anything they consider useful, and closing the rest.
 

JFC Fuller

ACCESS: Top Secret
Senior Member
Joined
Apr 22, 2012
Messages
2,607
Reaction score
870
BAE is consolidating its Swedish operations after they lost both the Swedish wheeled vehicle requirement and the UK FRES-SV requirement. In short the Swedish operation did not have enough work to stay the size it was.
 

Grey Havoc

The path not taken.
Senior Member
Joined
Oct 9, 2009
Messages
11,940
Reaction score
2,083
'Organic camouflage': http://www.militaryphotos.net/forums/showthread.php?204414-A-libyan-tank-with-sheep-s-skin-camouflage ;D
 

Grey Havoc

The path not taken.
Senior Member
Joined
Oct 9, 2009
Messages
11,940
Reaction score
2,083
Military wise, this will probably be more relevant to naval applications in the short term: Physicists Create Magnetic Invisibility Cloak (ScienceNOW via Wired.com)

But that doesn’t make a superconducting can a magnetic cloak. That’s because outside the can, the field produced by the superconductor will alter the applied field and reveal its presence. In a nutshell, the field can be thought of as a distribution of lines of force that vaguely resembles a weather map of winds. The superconducting shield pushes the magnetic field lines outward, creating a hole in the field. So the trick to making a cloak for static magnetic fields is to counteract that distortion. In 2007, Pendry and Ben Wood, also of Imperial College London, proposed that such a cloak could be made of a material that repels magnetic fields in one direction and attracts them in the opposite direction. Unfortunately, this self-contradicting material doesn’t exist.

But Alvaro Sanchez of the Autonomous University of Barcelona in Spain and colleagues propose a way to approximate the impossible stuff by wrapping the cylindrical shell of superconductor in layers of materials that do one job at a time. Some layers are easily magnetized and will essentially pull the external magnetic field lines around the cylinder; those layers alternate with shells of superconducting plates that push on the field, preventing it from coming straight in toward the center. The attracting layer would be made of tiny magnetic particles, like submicroscopic iron filings, mixed into a nonmagnetic material such as plastic.

The cloak could handle fields of any shape and any strength within what the superconductor can stand. If the external field gets too strong, the magnetically induced current becomes so powerful that it knocks the superconductor out of its resistance-free state and ruins its field-repelling qualities. Computer simulations showed that the cloak could work with as little as four layers, but with 10, it would guide a magnetic field nearly as well as a perfect cloak, as Sanchez and colleagues report today in the New Journal of Physics. “It doesn’t need to be a closed cylinder; it can be an open cylinder or open plate, although in this case the magnetic cloaking properties are reduced,” Sanchez says.

The hypothetical device would work as a magnetic cloak by creating a space that is protected from an external magnetic field while at the same time causing no telltale distortion of the field. Alternatively, it could also be used to conceal a magnetic object and prevent its magnetic field from extending out into space—a pie-in-the-sky dream for shoplifters trying to steal clothes pinned with magnetic security tags.


[IMAGE CREDIT: Wired.com]​
 

mithril

ACCESS: Confidential
Joined
Mar 12, 2009
Messages
113
Reaction score
5
certainly seems easily applicable to submarines. subs are already tubular, and being nigh invisible to MAD systems would take out one of the less noticable anti-sub detection options.
if you can layer the subs hull with anti-aucoustic metamaterials as well, you could reduce it's vulnerability to sonar too..



Grey Havoc said:
Military wise, this will probably be more relevant to naval applications in the short term: Physicists Create Magnetic Invisibility Cloak (ScienceNOW via Wired.com)

But that doesn’t make a superconducting can a magnetic cloak. That’s because outside the can, the field produced by the superconductor will alter the applied field and reveal its presence. In a nutshell, the field can be thought of as a distribution of lines of force that vaguely resembles a weather map of winds. The superconducting shield pushes the magnetic field lines outward, creating a hole in the field. So the trick to making a cloak for static magnetic fields is to counteract that distortion. In 2007, Pendry and Ben Wood, also of Imperial College London, proposed that such a cloak could be made of a material that repels magnetic fields in one direction and attracts them in the opposite direction. Unfortunately, this self-contradicting material doesn’t exist.

But Alvaro Sanchez of the Autonomous University of Barcelona in Spain and colleagues propose a way to approximate the impossible stuff by wrapping the cylindrical shell of superconductor in layers of materials that do one job at a time. Some layers are easily magnetized and will essentially pull the external magnetic field lines around the cylinder; those layers alternate with shells of superconducting plates that push on the field, preventing it from coming straight in toward the center. The attracting layer would be made of tiny magnetic particles, like submicroscopic iron filings, mixed into a nonmagnetic material such as plastic.

The cloak could handle fields of any shape and any strength within what the superconductor can stand. If the external field gets too strong, the magnetically induced current becomes so powerful that it knocks the superconductor out of its resistance-free state and ruins its field-repelling qualities. Computer simulations showed that the cloak could work with as little as four layers, but with 10, it would guide a magnetic field nearly as well as a perfect cloak, as Sanchez and colleagues report today in the New Journal of Physics. “It doesn’t need to be a closed cylinder; it can be an open cylinder or open plate, although in this case the magnetic cloaking properties are reduced,” Sanchez says.

The hypothetical device would work as a magnetic cloak by creating a space that is protected from an external magnetic field while at the same time causing no telltale distortion of the field. Alternatively, it could also be used to conceal a magnetic object and prevent its magnetic field from extending out into space—a pie-in-the-sky dream for shoplifters trying to steal clothes pinned with magnetic security tags.

[IMAGE CREDIT: Wired.com]​
 

bobbymike

ACCESS: USAP
Joined
Apr 21, 2009
Messages
10,412
Reaction score
1,361
VANCOUVER -- A Maple Ridge, B.C., inventor claims to have discovered what scientists, armies, children and science fiction fanatics have dreamed of for generations -- a fabric material that can make a person or object completely invisible.
“We were able to make a six-inch object disappear,” Guy Cramer said of his accidental discovery. “I went back to the shop and up-scaled the material and it worked just as well on a person.”
Cramer is the founder of HyperStealth Biotechnology, a company that designs digital camouflage patterns for clients including the Jordanian and Afghanistan armies. He said the Canadian and U.S. militaries are now discussing arrangements to potentially adopt his light-bending technology, which could potentially be used to hide entire airplanes and buildings.
“It can actually work in 360 degrees, so someone behind me can see what’s on the opposite side, and someone in front of me can see what’s behind me,” Cramer said of his fabric, which would put his discovery far ahead of currently known research.
“We’ve made an entire vehicle disappear.”
However, Cramer is not revealing any evidence of his invisible material — even the images posted on his website are photo illustrations.
“We can’t show it because someone will pick apart from those photos how it actually works,” he said.
 

Grey Havoc

The path not taken.
Senior Member
Joined
Oct 9, 2009
Messages
11,940
Reaction score
2,083
http://www.telegraph.co.uk/technology/news/9902307/Invisibility-cloak-unveiled-at-TED-conference.html

The invisibility cloak has long been a staple of science fiction, with Harry Potter famously using one in his wizard adventures.

But to gasps from the audience, a scientist from Nanyang Technological University in Singapore demonstrated an experiment that appears to make it more than the stuff of fantasy.

A small box made of calcite optical crystal was used to bend light around an object, making anything placed behind the box appear invisible to people watching the demonstration at the TED conference.

Professor Baile Zhang said he was inspired to create the invisibility device “just for fun”.

“I just think the idea is cool,” he said. “Plus, I hope this work will demonstrate that simple tools can sometimes fulfil important functions that previously required complicated methods.”

Professor Zhang admitted that his research was in its early stages, and said that his team was still working out how to make larger and more useful prototypes of the invisibility cloak, according to The Times.
 

shin_getter

ACCESS: Confidential
Joined
Jun 1, 2019
Messages
159
Reaction score
91
I wonder why stealth land vehicle doesn't seem all that popular. Is there a few sensors that can not be effectively neutralized at cost and thus rending the whole concept marginal?
 

GARGEAN

ACCESS: Secret
Joined
May 7, 2018
Messages
488
Reaction score
198
Unlike in the air, main ground search and targeting sensors are thermals and visual band. And those are much harder to work with, not talking about working against ground is much harder than working against sky.
 

Justo Miranda

ACCESS: Top Secret
Senior Member
Joined
Dec 2, 2007
Messages
4,438
Reaction score
2,376
Website
www.amazon.com
In the mid 90s, the advanced achieved in Computer Generated Holography, wavelength computation with Fourier transform method and Point Source Holograms, allowed the creation of holographic images in 3D around an object to hide it. But the system just worked with static objects and the Phased Array Optics required a considerable amount of electronic equipment.

In 2003, researchers at the University of Tokyo developed an active camouflage system with video cameras that registered the background to project it against the object that should be camouflaged.

In 2004, the discovery of the graphene made possible the manufacturing of curve video screens and adapts them to any surface. An vehicle with a coat of grapheme screens and equipped with video cameras that register the background from any angle and project it on the screens at the other side, may become practically invisible.

The layers of graphene are super-thin and several of them, with different properties, may be superimposed. Under the optical screen, it is possible to locate a layer formed by hexagonal elements of grapheme that may be heated or cooled down in a selective way, thanks to the Adaptiv system, developed by BAE systems in 2011. This layer would very efficiently act as infra-red camouflage.
 

Similar threads

Top