Now, perhaps more than ever, engineers & scientists are taking inspiration from nature when developing new technologies. This is often also true for the smallest flying structure humans have built to date.
Inspired by way trees like maples, disperse their seeds using little more than a stiff breeze, researchers developed many of small flying microchips, smallest one hardly bigger than a grain of sand.
This flying microchip or ‘microflier’ catches wind & spins like of a helicopter towards the ground.
The microfliers, designed by a team at the Northwestern University in Illinois, can be full of ultra-miniaturized technology, including sensors, power sources, antennas for wireless communication, and even embedded-memory for data storage.
“Our goal was to add winged flight to small-scale electronic systems, with the idea that these capabilities would allow us to distribute highly functional, miniaturized electronic devices to sense the environment for contamination monitoring, population surveillance, or disease tracking,” says Northwestern’s John A. Rogers, who led the development of new device.
The team of engineers wanted to design devices that might stay in the air for as long as possible, allowing them to maximize the collection of relevant data.
When microflier falls through the air, its wings interact with the air to make a slow, stable rotational motion.
“We think that we beat nature. At least in the narrow sense that we’ve been able to build structures that fall with more stable trajectories, and at slower terminal velocities than equivalent seeds that you would see from plants or trees,” says Rogers.
“We were also ready to build these helicopter flying structures at sizes much smaller than those found in nature.”
Rogers believes, these devices could potentially be dropped from the sky en masse and dispersed to monitor environmental remediation efforts, after an oil spill or to trace levels of pollution at the different altitudes.
The irony of potentially-creating a new environmental pollutant, while trying to mitigate the consequences of another is not lost on Rogers & his team. In paper describing their work, authors relay these concerns:
“Efficient methods for recovery & disposal must be carefully considered. One solution that bypasses these issues exploits devices constructed from materials that naturally resorb into environment through a reaction and/or physical disintegration to benign end products.”
Fortunately, Rogers’ lab develops transient electronics that are capable of dissolving in water after they’re not useful. Using similar materials, he & his team aim to create fliers that would degrade & disappear in ground water over time.
“We fabricate such physically transient electronics systems, using degradable polymers, compostable conductors & dissolvable integrated circuit chips that naturally vanish into environmentally benign-end products when exposed to water,” says Rogers.
“We recognize that recovery of huge collections of microfliers could be difficult. To address this concern, these environmentally resorbable versions dissolve naturally & harmlessly.”
The research was published in the journal Nature.