“Flying” microchips could ride the wind to track air pollution

Researchers have created a winged microchip the size of a grain of sand that could be the smallest flying device ever made, Vice reported. They are designed to be carried by the wind and could be used in many applications, including monitoring disease and air pollution, according to an article published by Nature. At the same time, they could be made from biodegradable materials to avoid contamination of the environment.

The design of the flyers was inspired by the spinning of seeds from poplar and other trees. These slowly fall, spinning like helicopters so that they can be picked up by the wind and spread a long distance from the tree, thus increasing the range of the species.

The Northwestern University team ran with this idea but made it better and smaller. “We think we beat biology … we were able to build structures that follow a more stable trajectory at slower terminal velocities than equivalent seeds,” said senior professor John A. Rogers. “The other thing … is that we were able to make these helicopter flight structures that are much smaller than the seeds you would see in the natural world.”

They are not so small that the aerodynamics start to deteriorate, however. “All of the benefits of the helicopter design start to fade below a certain length scale, so we pushed it all the way, as far as we can or physics allow,” Rogers said. . Vice. “Below that size scale everything looks and falls like a sphere.”

The devices are also large enough to carry electronics, sensors, and power sources. The team tested several versions that could carry payloads like an antenna so that they could communicate wirelessly with a smartphone or with each other. Other sensors could monitor things like air acidity, water quality and solar radiation.

The flyers are still concepts at the moment and are not ready to be deployed in the atmosphere, but the team plans to expand their discoveries with different designs. The key is the use of biodegradable materials so that they do not persist in the environment.

“We do not view these devices … as permanent surveillance components, but rather as temporary components that serve a particular need of limited duration,” Rogers said. “That’s the way we look at it now: you watch for a month, then the devices go off, dissolve, and go, and you may have to redeploy them. “