Researchers unveil fabric-friendly NFC sensors that track tags, everyday objects — and people

NFC sensors and how they're used in textiles
SMART HOME: The NFC sensors can be used to track objects made of conductive materials such as a hand

Scientists at Carnegie Mellon University in Pittsburgh in the US have developed fabric-friendly NFC sensors that can be woven into the surface of everyday objects such as cushions and pillows and enable them to locate other objects and sense a human presence.

The sensors can be deployed in a near-field beamforming system known as TextileSense that “can track everyday objects made of conductive materials, like a human hand” and be used for a variety of functions, such as finding lost objects and controlling devices through gesture recognition.

“Imagine being able to control the television volume by waving your hand over a couch cushion, or turning lights on and off by touching a specific part of a pillow,” the researchers from the university’s WiTech Lab Laboratory for Emerging Wireless Technologies say.

“The team designed and fabricated specialised textile coils that can be woven into the fabric of the furniture and easily hidden by acrylic paint.

“By developing a near-field blind beamforming system to efficiently detect surrounding objects, these coils can sense the position of an object, like determining if a human is sitting on the couch or laying down.

“Using a data-driven approach to infer the locations of the objects, an experimental evaluation of TextileSense shows an average accuracy of 3.5cm in tracking the location of objects of interest within a few tens of centimetres of the furniture.”

“We achieved this by using multiple flexible NFC coil antennas embedded in ordinary and irregularly shaped surfaces, like furniture and carpets, we interact with in smart environments,” adds Swarun Kumar from the research team.

“Our goal is to integrate these sensors in our everyday lives, which will contribute to an overall smart environment.”

Paper

The TextileSense system is explained in Locating Everyday Objects using NFC Textiles, a paper presented at the ACM’s annual Information Processing in Sensor Networks (IPSN) conference in May, where it won the best paper and best presentation awards.

In the paper the researchers summarize TextileSense as “a near-field beamforming system which can track everyday objects made of conductive materials (e.g. a human hand) even if they are a few tens of centimetres away.”

TextileSense’s multiple coils “together operate as a near-field MIMO system and can manipulate the near-field to recognize objects of interest at unknown locations across farther distances,” they explain.

The researchers go on to describe how the system can be used to sense two classes of objects — “tagged non-conductive objects, such as NFC-enabled credit cards and key fobs, whose identity and location can be obtained” and “untagged conductive objects, such as human hands and metallic objects, whose presence and location can be identified”.

A short video shows the technology in use.

Next: Visit the NFCW Expo to find new suppliers and access free resources