24 Aug Science or sinister?
The lead scientist being Chinese doesn’t help much, either
The human skin is a fascinating organ. In fact, it is the largest and heaviest organ of the human
body, extending to about 20 square feet, on average.
The skin's main function is protective; it creates a barrier between our insides and the external
world. However, skin does a lot more than protect us.
The various layers of skin create new cells, give the skin its color, and store fat. The skin also
helps control body temperature and water loss, and it contains nerve endings that help us detect
pressure, vibration, touch, and pain.
Our skin can give much away about our internal states, as outward signs of physiological
changes can provide a window into our physical and emotional conditions. Researchers use the
galvanic skin response, for example, to gain insights into a person’s levels of arousal, stress,
excitement, engagement, frustration, and anger.
Now, scientists have developed a way to harness these skin signals with a device that does not
require batteries, wires, or chips.
Zhenan Bao, a professor of chemical engineering at Stanford University, in California, and her
the team have designed a patch that sticks to skin like a Band-Aid and measures how a person’s skin
stretches and contracts.
The device then sends these readings wirelessly to a receiver attached to the person’s clothes.
Based on these readings, the researchers were able to monitor a person's breathing and heart rate,
as well as their arm and leg movements.
Prof. Bao and the team describe their wearable tech device in the journal Nature Electronics.
The researchers named their device body area sensor network or BodyNET, and they define
it as a collection of networked sensors that can be used to monitor human physiological
In the paper, the researchers describe how they tested the BodyNET. They stuck the sensors to
the wrist and abdomen of a participant to detect their pulse and breathing.
Placing the sensors on the participant's elbows and knees let the researchers know when the
the person moved, as the patch detected the stretching and contracting of the skin in the areas that
corresponded to the muscles flexed.
The BodyNET works using radiofrequency identification (RFID) — a technology that is also
used in keyless access systems and key cards.
With key cards, an antenna in the card picks up RFID energy from the receiver and uses it to
generate a passcode. The card then sends this passcode back to the receiver.
For the BodyNET, the researchers had to find a way to transmit RFID energy through an antenna
that could expand, contract, and bend along with the skin.
The scientists used metallic ink to create this antenna, but they soon realized that the signal
wasn't strong enough to keep up with the constant movements and fluctuations of the antenna
So, they designed a novel, stronger type of RFID system that would send more stable and
accurate signals. This innovative system also uses Bluetooth technology to send the readings
from the receiver to a smartphone or any other wireless device.
The researchers hope that healthcare professionals will use the device to monitor people with
sleeping problems and heart conditions. For the team, the next steps are to figure out how the
patch can also detect sweat and temperature.
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 behavior.