Now 3D Printed Sensors Without Circuitry Connects to WiFi


Imagine a laundry bottle that will order refill online as soon as it runs out or a volume slider that connects to the speakers without any wire or power source. This will be real very soon.University of Washington researchers for the first time have made 3D printed sensors and plastic objects that can collect useful data and communicate with other WiFi-connected devices entirely on their own.

The technique Printed WiFi allows these objects to transfer data wirelessly to any WiFi receiver using ambient WiFi from any router.These printed devices either absorb or reflect WiFi signals to convey 0 or 1. These kinds of techniques are called backscattering or reflecting waves which in this case are WiFi signals.

In the design, they have replaced some functions normally performed by electrical components with mechanical motion activated by springs, gears, switches and other parts that can be 3-D printed borrowing from principles allowing battery-free watches to keep time.A switch is attached with a spring. A plastic gear presses against a switch which makes contact with 3D printed antenna made of conducting film. When switch makes contact with the antenna signal, the transition is quick in amplitude.

“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. The interaction between the 3-D printed switch and antenna wirelessly transmits that data,” said senior author Shyam Gollakota, an associate professor in the Paul G Allen School of Computer Science and Engineering. “Then the receiver can track how much detergent you have left and when it dips below a certain amount, it can automatically send a message to your Amazon app to order more,” he added.

The team has 3-D printed several different tools that are able to sense and send information successfully to other connected devices like a wind meter, a water flow meter and a scale.They also have 3-D printed WiFi input widgets such as buttons, knobs and sliders that can be customized to communicate with other smart devices in the home and enable a rich ecosystem of ‘talking objects’ that can seamlessly sense and interact with their surroundings.