Guess what — even objects that don't have any power or electricity running through them can essentially become internet-of-things devices.

How? Well, researchers from the University of Washington have developed a way for 3D-printed plastic objects to communicate via Wi-Fi without the help of a power source whatsoever. This can be done, they've found, with commercially available plastics and Wi-Fi receivers.

Everyday Objects That Can Send Wi-Fi Signals

"Our goal was to create something that just comes out of your 3D printer at home and can send useful information to other devices," said Vikram Iyer, one of the authors of the study, and a doctoral student of electrical engineering at the university.

According to Iyer, the challenge was to create an object that can communicate wirelessly with Wi-Fi using only plastic, a feat that has never been done before.

To achieve this, the researchers 3D-printed springs, gears, and switches, the motions of which could be translated into antenna-transmitted information. For instance, they made an anemometer, a tool used to measure wind speed, then integrated it to a gear. Whenever the gear spins, its teeth make contact with the antenna embedded into the object. The antenna then sends out ambient Wi-Fi signal, which goes to a Wi-Fi receiver to be decoded.

They created other things as well, such as a scale and a flowmeter that can measure water speed.

Possible Real-World Uses

An object that can communicate via Wi-Fi without a power source. Amazing. But so what? How could this be useful? Well, here's an example: the researchers were able to create a detergent bottle with an integrated flowmeter that tracks the amount of detergent inside. When it detects that it's low, it can send out a Wi-Fi signal to order another one.

"As you pour detergent out of a Tide bottle, for instance, the speed at which the gears are turning tells you how much soap is flowing out," said Shyam Gollakota, one of the authors of the study, and an associate professor in the Paul G. Allen School of Computer Science & Engineering. "The interaction between the 3-D printed switch and antenna wirelessly transmits that data."

They were also able to find a way to print iron into 3D objects that, when scanned by a smartphone, shows information about that object.

The researchers are making their work available for all, so that basically anyone will be able to take advantage of these objects at home, provided they have a 3D printer, of course.

Below is a video showing the researchers' work in detail.