Camouflage has been used to protect military equipment such as vehicles, guns, ships, aircraft and buildings as well as individual soldiers and their positions. Vehicle camouflage methods begin with paint, which offers at best only limited effectiveness.
However a new threat has emerged of Gun and Vehicle Mounted thermal Sights , through which adversary can exercise long-range surveillance, rapid identification and location for our forces. These Thermal vision cameras make pictures or video from heat, not visible light which make it easy to spot human targets in complete darkness. These instruments do not directly measure the temperatures of the different targets in their field, but merely display the temperature differences of these targets according to a scale of colors or light intensities. Heat vision cameras detect the tiny differences in heat, even as small as 0.01° Celsius.
Any hot body can be detected by IR emitted using a thermal imager, and such equipment represents a real challenge for anyone or anything wishing to go unnoticed. You may have the best camouflage, but you will be quite visible to anyone with an infrared telescope, or the camera of a drone flying over your head.
Developing the thermal camouflage – or the appearance of being the same temperature as one’s environment – is much more difficult. Therefore researchers are developing infrared camouflage technology to avoid detection from high-end thermal imaging. Some methods for stationary land vehicles include covering with improvised materials such as blankets and vegetation, and erecting nets, screens and soft covers which may suitably reflect, scatter or absorb near infrared and radar waves.
The next-generation netting is expected to offer state-of-the-art signature concealment for “multispectral protection.” The Army awarded contracts a year ago for engineering, manufacturing and developing the new Ultra-Lightweight Camouflage Net System, or ULCANS. Another concept, albeit still in its early stages, is the US Army’s Improved Ghillie System (IGS), touted to replace the existing Flame Resistant Ghillie System, designed specifically for the 3,300 snipers across the US Armed Forces. The idea is to create a much simpler and modular IGS with equipment that snipers want to use. The IGS project is still in the testing phase and so far lots of variations have been designed by different defence firms.
The key to the camouflage is the electronic signature, both from heat produced by humans and vehicles and also the invisible signature of electronic systems, Milley said at a House Appropriations Committee hearing on Army modernization. “We know that adversary acquisition systems are very, very capable,” Milley said. Those camo systems, from netting strung over vehicles to ghillie suits used by snipers, break up electronic or heat signatures, he said.
Meanwhile Russia’s Ratnik-3 exoskeleton concept, developed in collaboration with Rostec and the University of Science and Technology in Moscow, employs both a thermal imaging infrared camera built into the helmet that can detect enemy body temperatures, and a protective camouflage technology in the torso that hides the wearer’s thermal signature.Ratnik-3 protects the torso through a newly developed material that hides a soldier from infrared imaging by containing all of the soldier’s body heat within the suit. The wearer even has the ability to adjust the inner temperature of the suit to manipulate their thermal signature.
Thermal Camouflage solutions
One method for blocking IRs, simple and effective, can be provided by a silver cover (survival blanket), or a Mylar sheet. The problem with such devices is that no matter what body or material you want to hide below, its heat will increase to an unbearable temperature, or escape to any place that will then be visible to infrared imaging. In this case, such dissimulation will be temporary, unless a particular system is developed which makes it possible to disperse the thermal signature.
A quick way to hide temporarily is to simply cover yourself with a blanket even a poncho, a tarpaulin, or an unfolded down, as is usually available on field trips. A thick wool blanket, for example, will help “beat” an image or thermal finder. It is covered with an insulating layer so that the heat is blocked (or partially blocked) and does not radiate outside. But again, it is only temporary concealment, insofar as the heat will gradually increase under the cover until eventually escape.
A camouflage net could also help, except that the holes would inevitably escape some of the thermal signatures. A net, however, would help disperse the heat beneath, as the airflow would be “broken” somewhere by the mesh, and diffuse that from the hottest parts, which would always be better than nothing.
A new type of camouflage makes a human hand invisible to a thermal camera
Most state-of-the-art night-vision devices are based on thermal imaging. Thermal cameras detect infrared radiation emitted by an object, which increases with the object’s temperature. When viewed through a night-vision device, humans and other warm-blooded animals stand out against the cooler background. Previously, scientists have tried to develop thermal camouflage for various applications, but they have encountered problems such as slow response speed, lack of adaptability to different temperatures and the requirement for rigid materials. Coskun Kocabas and coworkers wanted to develop a fast, rapidly adaptable and flexible material.
The researchers’ new camouflage system contains a top electrode with layers of graphene and a bottom electrode made of a gold coating on heat-resistant nylon. Sandwiched between the electrodes is a membrane soaked with an ionic liquid, which contains positively and negatively charged ions. When a small voltage is applied, the ions travel into the graphene, reducing the emission of infrared radiation from the camo’s surface. The system is thin, light and easy to bend around objects. The team showed that they could thermally camouflage a person’s hand. They also could make the device thermally indistinguishable from its surroundings, in both warmer and cooler environments. The system could lead to new technologies for thermal camouflage and adaptive heat shields for satellites, the researchers say.
‘Invisibility’ Material Offers Thermal Camouflage
Gorodetsky led the development of the adaptive camouflage materials that change their infrared reflectance on demand, enabling the surface to acquire desired – and potentially deceiving – thermal signatures when visualized under an infrared camera. After being stretched or electrically triggered, the material’s thin swatches quickly change heat reflectance, smoothing or wrinkling their surfaces in under a second. The modulation of apparent temperatures enables an invisibility to infrared night-vision tools. “It goes from wrinkled and dull to smooth and shiny, essentially changing the way it reflects the heat,” said Gorodetsky of the material.
“Essentially, you start out with a surface that’s wrinkled. The wrinkles are tens to hundreds of microns scale, and then you flatten that surface. In those two states is where you have the differences in how the material reflects heat or infrared light.” In the flattened state, the material reflects the heat right back at you. In the wrinkled state, the material scatters the heat, so it doesn’t come right back at the source, or at a camera, that’s looking at heat reflection. Being able to go between those two states is what gives these adaptive properties to the material. When you look at that surface under an infrared camera, those two states will look very different and they’ll have very different apparent temperatures. That effectively lets the material reappear and disappear under an infrared camera.
The camouflage aspect is one, for example, for security applications, but there are many common technologies that rely on controlling thermal radiation. For example, you could create windows on buildings that in one state might reflect heat, but in another state might let it in to maintain the temperature of the building.