Whilst wearable technology has allowed us to monitor our activity in a variety of interesting new ways, perhaps the most interesting angle is in developments in the actual fabric itself. The latest example comes via the University of Maryland, whose researchers have developed a fabric that can automatically regulate the amount of heat that passes through it.
The work, which was documented in a recently published paper, saw the construction of a smart fabric from specially engineered yarn that had been coated with a conductive metal. This changes how the fabric interacts with infrared radiation, which in turn transmits or blocks heat.
The fabric is made of a couple of fibers, one of which is designed to absorb water whilst the other aims to repel it. The strands of the fiber are then coated with carbon nanotubes, and when the fibers are exposed to humidity, they warp, thus bringing the strands closer together. This then opens up the pores in the fabric, which allows heat to escape and cools the wearer, but it also modifies the electromagnetic coupling between the carbon nanotubes.
“You can think of this coupling effect like the bending of a radio antenna to change the wavelength or frequency it resonates with,” the researchers say. “It’s a very simplified way to think of it, but imagine bringing two antennae close together to regulate the kind of electromagnetic wave they pick up. When the fibers are brought closer together, the radiation they interact with changes. In clothing, that means the fabric interacts with the heat radiating from the human body.”
Heat management
The fabric is then able to either block infrared radiation from passing through or allow it, depending on the nature of the tuning. What’s more, this reaction is pretty much instant, so it occurs before people even realize they’re getting hot or cold.
“The human body is a perfect radiator. It gives off heat quickly,” the researchers say. “For all of history, the only way to regulate the radiator has been to take clothes off or put clothes on. But this fabric is a true bidirectional regulator.”
The team believe that they’re the first to create such a fabric that can smartly regulate the heat exchange with the environment. There is obviously a lot more work required before the fabric can make it to market, but the team are confident that it can do so. All of the materials used for the fabric are readily available, and it’s a straightforward process to add carbon coating to it during the dying process.
“I think it’s very exciting to be able to apply this gating phenomenon to the development of a textile that has the ability to improve the functionality of clothing and other fabrics,” the researchers conclude.
