Momentum - The Magazine for Virginia Tech Mechanical Engineering Vol. 1 No. 2 | Page 12

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At left, Pinhas Ben-Tzvi, associate professor and
director of the robotics and mechatronics lab, discusses
the actuator speed of his robotic exoskeleton with Eric
Refour a master's student in electrical and computer
engineering. Below Refour demonstrates how the glove
fits over the thumb and index finger, with pneumatic
actuators snapping the fingers together. The glove is
made using additive manufacturing and the electronics
are designed and fashioned in Ben-Tzvi's lab.

Article & Photos Rosaire Bushey

Exoskeleton altered
to help cerebral palsy
diagnosis in children
It’s not often a highly complicated
piece of hardware needs to appeal
to 12-36 month olds to be effective.
But, to be fair, it’s not often they are
designed to fit on a child’s hand.
Pinhas Ben-Tzvi, associate professor of mechanical engineering and
founding director of the department’s
robotics and mechatronics lab, has
been working with robotic exoskeletons for years and on medical diagnostic robotics systems since his time
with General Electric Medical Systems
from 2000 to 2002. So when he was
called by Nathalie Maitre, a medical doctor at Nationwide Children’s
Hospital in Columbus, Ohio to see if
his Sensing and Force-Feedback Exoskeleton (SAFE) robotic glove could
be modified to help provide an early
diagnosis of cerebral palsy in children,
he was intrigued.
“Doctor Maitre proposed to fit a
modified version of my glove to a
child in an effort to apply somatosensory stimuli to measure cortical
responses for the early detection
of cerebral palsy,” Ben-Tzvi said.
The device is currently being
developed for adult-sized hands
and will be created and tested
at the larger size before being
scaled to fit a child.
“There’s a couple of really
challenging aspects to this project,” said Ben-Tzvi. “The first, of
course, is the typical challenge
we all face in making something
work. But then we have two
additional engineering challeng-

es here – to make it much smaller
and to make it look child friendly so it
doesn’t scare the children who have
to use it.”
The glove as it currently exists,
features pneumatically or electrically
actuated ‘fingers’ that connect to
a wrist-mounted baseplate and via
straps to the fingertips. It’s far more
like something out of Terminator than
Doc McStuffins.
The plan for the device is broken
into two phases with the first calling
for fitting the device on the hands of
children 12-36 months old using only
a thumb and forefinger to initiate a
pincer grasp. The glove would provide tactile feedback. The child would
have brain sensors connected to the
hospital’s Net Station software for
electroencephalogram (EEG) acquisition while the robotic device initiates
the pincer grasp and acquires finger
position, tactile and other data. The
EEG records brain wave patterns to

detect electrical activity abnormalities in the brain
In Phase two, testing would continue with toddlers to establish baseline
values for cortical responses and
sensorimotor responses using 20 children who were developing typically,
and five who were diagnosed with
cerebral palsy.
“There is a good deal of potential for
the device and it’s an interesting application of a product that was mainly
intended for hand rehabilitation for
stroke victims,” Ben-Tzvi said. “I think
anytime your work can be modified
to help identify a medical issue more
quickly, the more beneficial it becomes for the patient a nd the more
options it allows for in treatment.
The fact we are taking a device made
to deal with after-the-fact issues,
and using it to possibly help make an
earlier diagnosis of an issue, is very
exciting.”