Work is underway at US universities on technology to improve wearable sensors.
Researchers at University of Delaware are exploring a method to bring magnetic sensors closer to new materials possessing extreme short-range magnetic fields of just three to four angstroms.
They have developed atomically thin semiconductor materials that can be laid atop of a magnetic material to get closer than before. Features within the ultra-thin layer can then serve as the sensing element.
It turns out that tiny crystal defects in the semiconductor layer can act as light-emitting sensors, which then provide information about magnetization and local magnetic field. The work by the Chitraleema Chakraborty lab at UD is supported by a $500,000 award from the National Science Foundation.
The team’s latest effort is to deliberately introduce and stabilize the defects in the semiconductor layer, and early results show such engineered defects can survive at room temperature, making that approach more practical. In the future, research will test whether the defects respond predictably to magnetic fields so they can look for measurable optical changes, including brightness and color.
“If successful, this could lead to devices that function as sensors and extend beyond magnetic materials,” Chakraborty said in a report from UDaily. She is an assistant professor at UD.
She said flexible sensors in wearable systems could make brain imaging more precise and adaptable than today’s devices.
Background: Some advanced materials produce magnetic fields so short-range that today’s sensors cannot get close enough to measure them. Today’s magnetic sensors are usually embedded in a bulk material which leaves a gap between the sensing element and the source of the magnetic field. As UDaily explained, some emerging magnetic materials have short-range fields that decay within three to four angstroms, just a few atoms wide. That’s a distance too small for existing sensors to get close enough to measure signals directly.
AdapSkin at Michigan State
Separate work by engineers at Michigan State University has led to a soft, flexible wearable sensor platform called AdapSkin that improves the capture of the body’s electrical signals. According to a story in Design World, the innovation helps AI system interpret movement more accurately in the control of prosthetic devices.
The tech has improved gesture recognition accuracy in older adults to 97% up from about 60%. Aging skin changes signal quality, which is why AdapSkin is helpful. It uses soft stretchable electronics that conform closely to the skin and maintain stable contact and skin comfort during movement.