University of Washington researchers have developed non-electronic, 3D printed devices that can track and store their own use.
The system powers itself using a method called backscatter, which enables the device to share information by reflecting signals that have been transmitted to it via an antenna.
According to the researchers, the 3D printed devices are perfect for assistive technology, like prosthetics or smart pill bottles that remind patients to take their daily medications.
The team – which includes professor Jennifer Mankoff – had previously developed 3D printed objects that connect to Wi-Fi without electronics.
These purely plastic devices can measure if a detergent bottle is running low and then automatically order more online.
“Using plastic for these applications means you don’t have to worry about batteries running out or your device getting wet. That can transform the way we think of computing,” said senior author and associate professor Shyam Gollakota. “But if we really want to transform 3D printed objects into smart objects, we need mechanisms to monitor and store data.”
In their previous study, the researchers developed a system that could track movement in one direction, which worked well for monitoring laundry detergent levels or measuring wind or water speed.
The current study required them to make objects that could monitor bidirectional motion like the opening and closing of a pill bottle.
For this purpose, the researchers used two antennas – one on top and one on bottom – that can be contacted by a switch attached to a gear.
Opening a pill bottle cap moves the gear in one direction, which pushes the switch to contact one of the two antennas.
Closing the pill bottle cap turns the gear in the opposite direction, causing the switch to hit the other antenna.
In addition to tracking pill bottle cap movement, this same method can also be used to monitor how people utilize prosthetics, such as 3D printed e-NABLE arms.
These mechanical hands, which attach at the wrist, are designed to help children with hand abnormalities grasp objects.
When children flex their wrists, cables on the hand tighten to make the fingers close.
As part of their study, the researchers 3D printed an e-NABLE arm with a prototype of their bidirectional sensor that monitors how the hand opens and closes by determining the angle of the wrist.
Image, video and content: Mark Stone/University of Washington