A new type of smoke grenade, which is currently under development, offers soldiers a cloak of invisibility in both visual as well as infrared (IR) spectra.
Smoke grenades have been used for many years now and are even effective enough, notes a report by Phys.org, to even cover tanks on the move. The new grenade aims to create a cloud of smoke that can actually provide a shield against IR.
"Because of the advancement of sensors beyond the visible region, we need new, high-performing obscurants in the infrared region," says Zach Zander, a researcher at the U.S. Army's Edgewood Chemical Biological Center.
"Each obscurant can absorb or scatter light at a given frequency. Most of the smokes that we use do well in either the visible or IR range. The objective of this program is to create what we call a bispectral obscurant, which works to block visible, as well as infrared detection," he added.
A mainstay in any army, smoke grenades offer a screen of temporary invisibility to soldiers in combat by visually obscuring them in a cloud. While it is easy to hide inside a cloud of smoke, they offer little to no cover against IR sensors. An enemy equipped with IR technology, looking for heat signatures will be able to easily identify a person in a smoke cloud.
Another objective of this research is to make a smoke screen with less toxic chemicals. "The traditional army smoke grenade is made with a toxic material, called hexachloroethane, but terephthalic acid grenades are emerging as a safer alternative," says Zander.
The acid compound, called UiO-66 also contains a zirconium node surrounded by large pores that the scientists say can effectively mask IR.
The challenge is to have both aspects, the non-toxic smokescreen as well as the IR absorption happen simultaneously, notes the report.
The plan is to create a smokescreen from one single grenade that covers multiple spectra from visible light to IR and more instead of having to drop different devices for each. The researchers say they want to create something like a Swiss Army knife of smoke grenades.