for National Geographic News
We're accustomed to borrowing from animals and plants when it comes to clothing ourselves. Wool, cashmere, cotton, and the like all help to keep out the cold.
But what about clothing that keeps us from overheating? Short of stripping, this isn't such an easy problem to solve.
Yet scientists may have done just that. Again, their inspiration comes from nature, but not from sheep or cotton plants. Actually, it grows on evergreen trees.
Britain-based researchers are now creating a new fabric that they claim adjusts automatically to changing body temperatures to keep the wearer cool. Its design is based on the mechanism used by pine cones to shed their seeds. This so-called smart clothing is being developed in England at the University of Bath's Centre for Biomimetics.
The department's head, Julian Vincent, said, "We've all known days when the weather alters quickly and it's difficult to dress to match the changing temperature. The new smart clothing will make all that unnecessary."
Biomimetics is the concept of taking ideas fine-tuned by nature over millions of years and mimicking them to develop cutting edge designs and products. This isn't a new disciplinein the 15th century Leonardo da Vinci designed flying machines based on his studies of birds. But recently biomimetics has become the focus of increased scientific investigation.
Work on the new smart fabric first began after an approach from the U.K. government. Military chiefs were seeking a more efficient field-clothing system for Britain's armed forces.
Vincent said, "When you get hot you produce perspiration, and we wanted something to get rid of the sweat. So we looked around in the plant world for mechanisms where a change in humidity causes a change in shape. Actually, there are quite a lot of them, such as peapods, which go bang when they dry out. But the pinecone turned out to be the best model."
Pinecones remain closed while growing on trees, but after they drop they gradually open, allowing their seeds to be released. They can do this because the cone's scales have two layers of stiff fibers that run in different directions.
The inside of the scale expands more than the outside as the cone dries out. This causes the scale to bend outward.
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