Built from PEDOT-Cl-treated cotton, this woven sensor is sensitive enough to pick up heartbeats but strong enough to withstand a hug.
Researchers at the University of Massachusetts Amherst have created an all-fabric pressure sensor which, they say, uses a breakthrough new material that could help solve one of the thorniest problems in wearable pressure sensing.
“Imagine comfortable clothing that would monitor your body’s movements and vital signs continuously, over long periods of time,” says Trisha L. Andrew, professor and co-author of the paper detailing the woven pressure sensor. “Such clothing would give clinicians fine-grained details for remote detection of disease or physiological issues.”
Wearable sensors of this nature are nothing new, of course, and plenty of designs have already been used this way. But, the researchers claim, they all share the same problem: an inability to cope with natural variations in pressure when the user lies down, or accepts a hug, or any of a number of other motions which impact on the sensor. “That increased pressure overwhelms the sensor, interrupting the flow of data, and so the sensor becomes useless for monitoring natural phenomena,” Andrew explains.
That’s where the new, fully-woven sensor comes in. Developed using cotton vapor-printed with a piezoionic material called PEDOT-Cl, the fabric sensor works by turning movements — even as small as a heartbeat — into an electrical signal by redistributing ions throughout the material. Unlike its rivals, though, it doesn’t care when the pressure gets turned up — and it’s suitable for use in loose-fitting clothing, making it more comfortable and easier to integrate into patients’ natural routines.
“This is the first fabric-based sensor allowing for real-time monitoring of sensitive target populations,” claims lead author Zohreh Homayounfar, a graduate student at UMass Amherst, “from workers laboring in stressful industrial settings, to kids and rehabilitation patients.”
The team’s work, which proved the longevity and sensitivity of the device, has been published in the journal Advanced Materials Technologies under closed-access terms.
Source: https://www.hackster.io/