Fly away, little sensors! These tiny wireless devices can be scattered by the wind – TechCrunch
If you want to monitor temperature, humidity, and exposure across 100 square miles of forest, you’re going to spend a lot of time tying up tech trees. What if you could scatter your sensors the way dandelions and elms scatter their seeds? UW researchers have developed devices that are light enough to be carried by the wind.
The project pushes the boundaries of small-scale, purpose-built computing, and although it’s still a prototype, it’s an exciting direction for on-board electronics.
“Our prototype suggests that you could use a drone to release thousands of these devices in a single drop. They’ll all be carried by the wind a little bit differently, and basically you can create a network of 1,000 devices with that one drop,” said Shyam Gollakota, a UW professor and prolific device creator.
This is made possible mainly by the removal of any kind of battery, which considerably reduces the mass of the electronics. Equipped with just a few tiny sensors, a wireless transceiver, and a few tiny solar cells, the gadget itself weighs less than 30 milligrams.
Its wind-catching structure was obtained after dozens of attempts, finally resulting in this form of bicycle wheel like the one that both made the device travel far from its starting point but also land with the solar panels facing towards the top 95% of the time. Disseminated by drone, they can travel a hundred meters before settling.
Once they land, they will operate whenever it is daylight, using radio frequency backscatter to bounce their signals off the environment and among themselves, forming an ad hoc network that can be collected by a monitoring device .
That’s a far cry from the mobility of the miraculously light dandelion seed, which weighs a single milligram and can travel for miles. But nature has had eons to perfect its designs, with the UW team just getting started recently. The other challenge is, of course, the fact that the real seeds end up either turning into dandelions or decomposing into nothing – whereas a thousand sensors would remain until picked up or broken into parts. The team said they are working on this, although the field of biodegradable electronics is still young.
If they can understand the angle of e-waste (and presumably the angle of the animals eating it), that could be very helpful for people trying to keep a close eye on endangered ecosystems.
“This is just the first step, which is why it’s so exciting. There are so many other directions we can take now,” said lead author Vikram Iyer. The article describing their work appeared today in the journal Nature.