The Journal of mHealth Vol 1 Issue 6 (Dec 2014) | Page 14

Industry News

A Tiny Ultrasound-Powered Chip to
Serve as Medical Device
Stanford engineers are developing a way to send power, safely
and wirelessly, to “smart chips” in the body that are programmed
to perform medical tasks and report back the results.
The idea is to get rid of wires and batteries, which would make
the implant too big or clumsy.
Their approach involves directing ultrasound at a tiny device
inside the body designed to do three things: convert the incoming sound waves into electricity; process and execute medical
commands; and report the completed activity via a tiny built-in
radio antenna.
“We think this will enable researchers to develop a new generation of tiny implants designed for a wide array of medical applications,” said Amin Arbabian, an assistant professor of electrical engineering at Stanford.
Arbabian’s team recently presented a working prototype of this
wireless medical implant system at the IEEE Custom Integrated
Circuits Conference in San Jose.
The researchers chose ultrasound to deliver wireless power to
their medical implants because it has been safely used in many
applications, such as foetal imaging, and can provide precision
and sufficient power to implants a millimetre or less in size.
Arbabian and his colleagues are collaborating with other
researchers to develop sound-powered implants for a variety of
medical applications, from studying the nervous system to treating the symptoms of Parkinson’s disease.
The Stanford medical implant chip is powered by piezoelectricity (pressure on a material generates an electric voltage). The

Stanford team created pressure by aiming ultrasound waves at a
tiny piece of piezoelectric material mounted on the device.
In the future, the team plans to extend the capabilities of the
implant chip to perform medical tasks, such as powering sensors or delivering therapeutic jolts of electricity right where a
patient feels pain.
The “smart chip” also contains an RF antenna to beam back
sensor readings or signal the completion of its therapeutic task.
The current prototype is the size of the head of a ballpoint
pen. The team hope to design a next-generation implant onetenth that size to interface with brain cells, using arrays of micro
implants across the entire 3D structure of the brain, and for
other uses. n

Fall Detector for the Elderly
Speeds Up Emergency Alerts
A wearable device that sets off an alert
when it detects a fall has been developed
to give elderly people reassurance that
emergency services will be contacted
instantaneously if they suffer an accident. Called FATE, or FAll DeTector
for the Elderly, the device uses technology similar to airbags in cars which are
triggered when sudden acceleration is
detected.

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FATE is a three-year European

December 2014

project that brings together a consortium
of technology and delivery partners.
The ultimate goal of the FATE project
is to widely validate an innovative and
efficient ICT-based solution focused on
improving elderly quality of life by providing an accurate detection of falls in
ageing people, both at home and outdoors. This is done by implementing
a portable and usable fall detector that
runs a complex and specific algorithm to

accurately detect falls, and a robust and
reliable telecommunications layer based
in ZigBee and Bluetooth technologies,
capable of sending alarms when the user
is both inside and outside the home.
The system is complemented by a number of secondary elements such as a bed
presence sensor and a device called the
i-Walker (an intelligent walker designed
to detect fall risk for older people with
significant gait difficulties). The idea is