metamaterial masking moves toward practical application

24 02 2011

Via Rachel Courtland, New Scientist. Issue 2800

NOW you see it, now it looks like something else. Radar images might never be the same again, thanks to an illusion device that can change an object’s appearance. The technology could ultimately be used to hide military aircraft.

The device is part of a growing family of metamaterials – structures designed to steer light along curved paths. They have already been used to make objects appear invisible and to disguise a gap between two objects.

Wei Xiang Jiang and Tie Jun Cui’s team at Southeast University in Nanjing, China, have created a structure that changes the way radio waves interact with a copper cylinder so that it appears to be composed of another material altogether.

Copper conducts electricity well and reflects incoming radio waves, giving it a bright radar signature. To alter this behaviour, the team built a device made of 11 concentric rings of circuit boards etched with small metal-lined channels that prevent electromagnetic waves reflecting away. Instead, they guide the waves in a direction that the researchers choose specifically to make the hidden object appear to have different electrical properties.

Placed around a copper cylinder, the arrangement created the illusion that the cylinder was made of a dielectric, a class of materials including porcelain and glass that do not conduct electricity and are more transparent to radio waves.

"Electromagnetic cloak"

A similar waveguide that rendered small objects invisible was tested in 2009.

The illusion only worked when the cylinder was viewed from the side; what’s more, the imaginary object it generated was the same size as the original. Future designs would have to account for all three dimensions, and might produce an illusion quite different from the object they disguise.

“In principle, this technology could be used to make an illusion of an arbitrary shape and size,” says Cui, whose team created an electromagnetic “black hole” for light in 2009. Similar illusion devices could eventually be used for stealth technology: for example, to “convert the radar image of an aircraft into a flying bird”, Cui says.

The work, which will be published in Physical Review E, is still at an early stage, however. At 45 millimetres, the team’s illusion device is three times as wide as the cylinder it disguised. “Their device is still fairly bulky relative to the original object, so further work needs to be done before a real device can be deployed,” says John Pendry of Imperial College London.

Although invisibility devices were invented first, the illusion technology might win the race to be put to practical use. “It is easier to falsify something than to hide it,” Pendry says.

The team next plans to explore ways to design devices with more complex shapes.





hyde definition’s new look

6 08 2010

Hyde Definition, the digital camouflage and concealment company I run, has finally finished revamping its website. Well actually, not quite, as there are still one or two things that need adding and tidying, but to all intents and purposes it is done. Come on over and take a look!

"Hyde Definition web page"





metamaterials, laser resin and invisibility cloaks

6 08 2010

Metamaterials can bend light around objects to render them near-invisible, begins a recent report in New Scientist. But it is an imperfect, lossy process, meaning some light is absorbed on its way through the metamaterial, and therefore the object remains semi-visible.

Now a team of scientists at Purdue University in West Lafayette, Indiana have invented a light amplifying resin ‘sandwich filling’ which, when stimulated by a laser, creates gain in the electro-optical signal, restoring the ‘lost’ light. The “negative-index metamaterial” means that an object can now conceivably be made  invisible to specific wavelengths of light.

Previous metamaterials, utilising nanoholes in a carbon matrix, IIRC, were able to mask objects in the microwave end of  the electromagnetic spectrum, but visible light has until now been elusive.

A wearable device is still light years away (pardon the pun!), but military installations, ships and even armoured vehicles are most definitely foreseeable near-term applications for the invisibility treatment.

Watch this space. Not that you’ll see anything ;-)





exclusive – government reveals strategy to camouflage national debt

1 04 2010

As seen in this morning’s FT. I’m a tad disappointed no-one from the media approached me for a subject matter expert comment on this. For instance, they forgot to mention mimetic resemblance, wherein a potentially dangerous thing (e.g. Quantitative Easing) pretends to be something harmless (i.e. charitable giving from a conjurer’s hat of magic money), like when the Canadian Freshwater Shark mimics a floating log in order to catch its favourite prey – lumberjacks. It’s a fishy business, government spin. Anyhow, my scanner isn’t working, so I took a photo of the article for posterity, and copied the content below (my italics added):

A secret Treasury memo leaked this morning reveals how the government intends to mask the enormity of our country’s crippling financial deficit, using classic subterfuge techniques commonly used by the military to disguise men and equipment.

The communiqué, issued from Chancellor Kevin Darling’s office, was addressed to Merkin King, governor of the Royal Bank of England.

It outlines steps – to be taken by spokespeople when issuing statements to the press about piscal policy – that are intended to obscure the size of the national debt, including:

• Dividing the deficit into sub-units, such as external and internal liability and short term and long term indebtedness, thus making the overall amount harder to perceive: this is similar to disruptive camouflage used by many animals to break up the contours and symmetry of their bodies or by soldiers to obscure the shapes of men, vehicles and aircraft.

Blending the debt against a background context of world insolvency, similar to camouflage colours and patterns employed by soldiers’ combat uniforms to match the environment.

• Diverting scrutiny away from the issue by focussing attention on the United States’ even more embarrassing monetary problems, known as misdirection by camouflage experts.

• Mentioning the amount of borrowing quickly and indistinctly whilst simultaneously coughing into a hand and waving at an imaginary friend across the road: another form of misdirection.

Pass this article on to all those you know – it’s time we call the politicians’ bluff and show them that they can’t pull the wool over our eyes!





multicam makes the cut in the dirtbox

22 02 2010

Following a pre-emptive announcement on Soldier Systems on Feb 17th, the US Army confirmed that it will be fielding Crye’s Multicam pattern in Afghanistan, replacing the maligned Universal Camouflage Pattern (UCP) and effectively ending trials of a recoloured derivative, UCP-D, that attempted to resolve some of the concealment issues around UCP by adding a fourth, earth (‘Coyote’) brown colour.

The Army Times has this:

By Matthew Cox – Staff writer
Posted : Sunday Feb 21, 2010 9:07:31 EST

The Army will begin fielding MultiCam, a more effective camouflage pattern for Afghanistan, in August. Soldiers deploying in late summer will be the first to receive the new versions of the Army Combat Uniform; soldiers already in theater will begin getting them in the fall.

MultiCam, made by Crye Precision LLC, bested the existing digital pattern and others in multiple Army tests.

MultiCam was “21 percent less detectable than UCP,” the pattern used in ACUs, said Col. Bill Cole, project manager for Soldier Protection and Individual Equipment.

“MultiCam was the clear winner,” he said.

Army Chief of Staff Gen. George Casey was convinced of MultiCam’s effectiveness based on that statistic, Cole said.

“He’s an infantryman … when he saw that, he said, ‘You mean I can get this much closer to the enemy before I’m seen?’” Cole said. “That’s what he wanted.”

Secretary of the Army John McHugh approved Casey’s recommendation Feb. 19.

The 4th Brigade Combat Team, 10th Mountain Division, at Fort Polk, La., and the Iowa National Guard’s 2nd Brigade Combat Team, 34th Infantry Division, will be the first to receive MultiCam. The new uniforms will also feature other improvements slated to be incorporated in all future ACUs over time, including an improved collar and buttons to replace some Velcro.

Soldiers will receive four sets of MultiCam uniforms, four combat shirts and matching combat gear, Cole said.

“Anything they would wear on a dismounted combat patrol will be in MultiCam,” Cole said.

The Feb. 19 announcement came after a multiphase effort that culminated with soldiers from Fort Bragg, N.C., Fort Campbell, Ky., and Fort Drum, N.Y., evaluating hundreds of calibrated photos of the Army’s Universal Camouflage Pattern and five alternative patterns taken in different settings in Afghanistan.

"021710at_multicam_2_800"

Soldiers wearing Multicam

So is MultiCam a step backward, returning camo design  to old-skool analogue patterns with swirly woodland shapes? Not at all! While it is not a pixellated pattern like UCP, the Marine’s MarPat, or Canada’s CadPat, it is still a digital designed pattern, and is far more advanced than any camo fielded in the 1980s and ’90s. Its design takes advantage of improvements in computer software that were unimaginable in the days of the Cold-war, allowing a complex pattern to be assembled from many different overlapping images, with colours tweaked to match environmental samples at the touch of a button. Before it was even printed, the concept was validated using sophisticated simulations of the pattern in different environments.





image of the day

10 02 2010
"LCpl Ross MacDougall, 1st Battalion Scots Guards, provides force protection during a CASAVAC Training Exercise during 4 Mechanized Brigade's Mission Specific Training (MST) on Salisbury Plain."

Picture: Sergeant Dan Harmer RLC, Crown Copyright/MOD 2010

Desert DPM: the British Army’s secret new-old multi-terrain camouflage!





dreamin’ of a white christmas?

23 12 2009
Finnish snow camo

Finnish M-05 snow camo on Strike-Hold!

Over at Strike-Hold!, Lawrence has been as busy as Santa’s elves collating a wish-list of  currently available (although how available might depend on who you are!) snow camouflage. Have you written your letter to QM Claus yet? If not, check it out!








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