around like a worm. The smart skin
may massage the legs of an astronaut,
or act as exoskeletons to help with
resistance exercises; the function
changes as the skin is peeled off, rotated, and replaced.
Kramer-Bottiglio’s ultimate hope
is that with a sufficiently malleable interior, the skins could have two types
of actuator. One would mold the interior to form appendages, while another type would move those appendages
around; in effect, forming a robot that
morphs based on the job it is asked
to perform. “It is a vision that we are
quite far from today,” she concedes.
Like other researchers into robotics, Kramer-Bottiglio faces two
key problems: force and control. Although the soft robots are made of
lighter materials than traditional robots and should be easier to move, it
is difficult to deliver large amounts
of power to the artificial muscles. Engineers are still many years from being able to emulate the high power-weight ratio of organic musculature.
Yale’s robotized toy horse makes slow
progress because the pneumatic ac-
tuators find it hard to bend its foam-
stuffed legs, and the use of open-loop
control leads to motion that is far less
coordinated than that of a real horse.
Not only that, most of these robots
need to be tethered to electronic and
pneumatic or hydraulic power sources, which limits their freedom.
A shift away from traditional elec-
tronic robot design and construction
could liberate soft automatons from
their tethers and help them move more
freely. Several years ago, Jennifer Lewis
and colleagues at Harvard University
were asked whether it was possible to
make a fully autonomous soft robot. In
attempting to design one, they moved
away from electronics, batteries, and
motors to a structure that could be
controlled by microfluidics.
The Octobot they produced pro-
vided the mechanics and core struc-
ture of an octopus-like robot made
from a sandwich of materials that are
not very different from the silicone
caulk used to line bathroom sinks.
However, the construction is much
more complex. As an experimentalist
with long-term involvement in three-
dimensional (3D) printing, Lewis and
her colleagues took advantage of the
technology’s ability to build complex
structures in layers. As it forms each
layer, the 3D printer works around the
voids that will become microfluidic
channels and pneumatic pipes used
to fuel and distort the limb’s shape.
Motive power for the Octobot’s
limbs comes from a supply of hydrogen
peroxide in the robot’s body. Micro-
fluidic channels controlled by a net-
work of tiny structures analogous
A shift away from
traditional electronic
robot design and
construction
could liberate soft
automatons from
their tethers
and help them
move more freely.
“Small, thin, and sleek” has long
been the mantra for designing
smartphones, smartwatches,
tablets, and laptops. A focus on
usability has driven advances
in form factors. Yet, one thing
has stayed the same: virtually all
computing devices remain rigid.
It is a challenge that has
vexed researchers struggling
to develop electronic displays
that can bend, fold, flex, and
roll—while containing batteries,
circuits, and other components.
Ultimately, every advance has led
to the same dead end: a display
that cannot stand up to the
rigors of everyday use.
However, that situation is
about to change. After decades
of research and false starts,
manufacturers are introducing
products with flexible displays.
Royole Corp. recently unveiled
a smartphone with a flexible
screen that allows the device to be
folded like a billfold; the product
has been available in China and
the U. S. since December 2018.
Meanwhile, Samsung plans
to introduce a smartphone with
a flexible display this year; others
are incorporating flexible designs
into products as well.
Says Vladimir Bulovic, a
professor of electrical engineering
at the Massachusetts Institute
of Technology (MI T), “Flexible
formats can be applied to many
devices.”
BEND, DON’T BREAK
New materials, better production
methods, and other advances
in technology have raised hopes
of viable flexible products. The
underlying OLED technology is
now at a point where it works
well, but encasing the displays in
plastic or ultra-thin glass remains
a challenge. Samsung’s foldable
smartphone, for example,
features an interior screen
that uses a composite polymer
transparent material to encase
a bendable AMOLED display.
The manufacturer claims the
Samsung Infinity Flex Display
can open and close 300,000 times
without suffering damage.
Other companies are also
moving flexible products from
the research lab to production.
Royole’s FlexPai device features a
7.8-inch 1440p AMOLED display
supported by a hinge that allows
the device to flex to almost any
desired angle. Royole also has
partnered with Airbus to produce
flexible electronics for aircraft,
and plans to produce clothing
with display technology.
Gregory Raupp, Foundation
Professor of Chemical
Engineering and founding
director of the Flexible Display
Center at Arizona State University,
says flexible technology could
impact fitness trackers, smart
watches, Internet of Things
devices, consumer electronics,
and industrial control systems.
Yet, some questions remain.
For one, “How do you deploy
that flimsy, plastic display into a
product that will be robust and
that the user won’t damage by
flexing it too much?” asks Raupp.
For another, “No one has
attempted to produce flexible
displays on a larger scale. Mass
production creates distinct
difficulties,” says William Stofega,
program director for Mobile Device
Technology and Trends at IDC.
Finally, and perhaps most
importantly, will the public desire
flexible devices? “The social
response to this technology is a
complete unknown,” Bulovic says.
Concludes Raupp, “We’re
now at a point where the
manufacturing problems have
largely been overcome and it is
a question of innovating and
integrating flexible displays in
new, unique, and novel ways. It’s
up to the design community to
transform ideas into reality.”
— Samuel Greengard is an
author and journalist based
in West Linn, OR, USA.
ACM News
Flexible Displays Enter the Picture