Scientists print sensors to make objects ‘self-aware’ of their surroundings

10 Oct 2018

Researchers have developed 3D-printed technology that can track and store objects’ use, without using batteries or electronics. Image: Mark Stone/University of Washington

In a major breakthrough, scientists have developed sensors to make a whole range of objects aware of their surroundings and track how they are used.

In the near future, the bottle that carries the medication prescribed by your doctor will be able to communicate with you, reminding you to take your pills or telling you if it is being stored in the right place.

This could be achieved with a new 3D-printed device developed by a team of researchers from the University of Washington that can make objects smart, without needing additional electronics or a battery. These devices are capable of tracking and storing their own use using a method called backscatter, through which a device can share information by reflecting signals that have been transmitted to it with an antenna.

“We’re interested in making accessible, assistive technology with 3D printing, but we have no easy way to know how people are using it,” said the study’s co-author, Jennifer Mankoff.

“Could we come up with a circuitless solution that could be printed on consumer-grade, off-the-shelf printers and allow the device itself to collect information? That’s what we showed was possible in this paper.”

The same team was behind the development of the first 3D-printed objects that connect to Wi-Fi without electronics. In that study, its system tracked movement in one direction – this works well for monitoring laundry detergent levels or measuring wind or water speed.

However, this latest study set out to find a way to make objects that could monitor bidirectional motion like the opening and closing of a pill bottle.

Explaining how the team achieved this, lead author Vikram Iyer said: “Last time, we had a gear that turned in one direction,” he said. “As liquid flowed through the gear, it would push a switch down to contact the antenna. This time we have two antennas, one on top and one on bottom, that can be contacted by a switch attached to a gear.”

Storing information

As both of the antennas are identical, the team had to find a way to differentiate between the pill bottle opening and closing, resulting in the coding of a specific sequence into each gear, similar to Morse code.

The researchers also wanted to create a 3D-printed object that could store its usage information while out of Wi-Fi range. For this application, they chose an insulin pen that could monitor its use and then signal when it was getting low.

Senior author Shyam Gollakota said: “You can still take insulin even if you don’t have a Wi-Fi connection. So, we needed a mechanism that stores how many times you used it. Once you’re back in the range, you can upload that stored data into the cloud.”

The team now aims to find a way to shrink these sensors so that they can be embedded in real pill bottles, prosthetics or insulin pens.

Colm Gorey was a senior journalist with Silicon Republic