US researchers develop skin sensors to wirelessly monitor health

19 August 2019 (Last Updated August 19th, 2019 11:55)

Researchers at Stanford University in the US have developed new sensors that can be adhered to the skin for wireless health monitoring.

US researchers develop skin sensors to wirelessly monitor health
Using metallic ink, researchers screen-print an antenna and sensor onto a stretchable sticker designed to adhere to the skin. Credit: Bao Lab/Stanford University.

Researchers at Stanford University in the US have developed new sensors that can be adhered to the skin for wireless health monitoring.

The sensors are designed to identify the physiological signals that the skin emanates, such as pulse. These readings will be wirelessly transmitted to a receiver clipped onto clothing. The sensor and receiver system has been named BodyNet.

To test the sensors, they were attached to the subject’s wrist and abdomen to track pulse and respiration by monitoring the way skin stretched and contracted with each heartbeat or breath.

The experimental stickers were also stuck to elbows and knees to track arm and leg motions via monitoring of how the skin tightened or relaxed with each corresponding muscle flexion.

The researchers expect BodyNet to initially be used for monitoring people suffering from sleep disorders or heart conditions.

They intend to further develop new sensors for monitoring body temperature and stress among other variables, through sensing of sweat and other secretions.

Over time, the team aims to create wireless skin sensors that will be paired with smart clothing to monitor different health indicators.

Stanford University School of Engineering professor Zhenan Bao said: “We think one day it will be possible to create a full-body skin-sensor array to collect physiological data without interfering with a person’s normal behaviour.”

The researchers used metallic ink for screen-printing a sensor and antenna onto a stretchable rubber sticker. The system eliminates the need for batteries or rigid circuits.

BodyNet’s antenna powers the sensors by harvesting some amount of the incoming radiofrequency identification (RFID) energy from the receiver clipped onto clothing. The antenna then captures readings from the skin and transmits them to the receiver.

The receiver, which is powered by battery, intermittently uploads data from the stickers through Bluetooth to a permanent storage system such as a smartphone or computer.

The researchers initially used tiny motion sensors for respiration and pulse monitoring. They intend to further enable the use of sweat, temperature and additional sensors.