Advanced Materials,
Journal Year:
2023,
Volume and Issue:
35(42)
Published: July 12, 2023
Auxetic
materials
are
appealing
due
to
their
unique
characteristics
of
transverse
expansion
while
being
axially
stretched.
Nevertheless,
current
auxetic
often
produced
by
the
introduction
diverse
geometric
structures
through
cutting
or
other
pore-making
processes,
which
heavily
weaken
mechanical
performance.
Inspired
skeleton-matrix
in
natural
organisms,
this
study
reports
an
integrated
elastomer
(IAE)
composed
high-modulus
cross-linked
poly(urethane-urea)
as
a
skeleton
and
low-modulus
non-cross-linked
complementary-shape
matrix.
Benefiting
from
disulfide
bonds
hydrogen-bond-promoted
dual
dynamic
interfacial
healing,
resulting
IAE
is
flat,
void-free,
has
no
sharp
soft-to-hard
interface.
Its
fracture
strength
elongation
at
break
increased
400%
150%,
respectively,
values
corrugated
re-entrant
alone,
negative
Poisson's
ratio
(NPR)
reserves
within
strain
range
0%-104%.
In
addition,
advantageous
properties
further
confirmed
finite
element
analysis.
The
concept
combining
two
dissimilar
polymers
into
hybrid
material
solves
problem
deterioration
performance
after
subtractive
manufacturing,
preserves
NPR
effect
large
deformation,
provides
promising
approach
robust
for
engineering
applications.
Advanced Materials,
Journal Year:
2024,
Volume and Issue:
36(33)
Published: June 22, 2024
By
incorporating
soft
materials
into
the
architecture,
flexible
mechanical
metamaterials
enable
promising
applications,
e.g.,
energy
modulation,
and
shape
morphing,
with
a
well-controllable
response,
but
suffer
from
spatial
temporal
programmability
towards
higher-level
intelligence.
One
feasible
solution
is
to
introduce
snapping
structures
then
tune
their
responses
by
accurately
tailoring
stress-strain
curves.
However,
owing
strongly
coupled
nonlinearity
of
structural
deformation
material
constitutive
model,
it
difficult
deduce
curves
using
conventional
ways.
Here,
machine
learning
pipeline
trained
finite
element
analysis
data
that
considers
those
nonlinearities
tailor
metamaterialfor
on-demand
response
an
accuracy
97.41%,
conforming
well
experiment.
Utilizing
established
approach,
absorption
efficiency
snapping-metamaterial-based
device
can
be
tuned
within
accessible
range
realize
different
rebound
heights
falling
ball,
actuators
spatially
temporally
programmed
achieve
synchronous
sequential
actuation
single
input.
Purely
relying
on
structure
designs,
tailored
increase
devices'
tunability/programmability.
Such
approach
potentially
extend
similar
nonlinear
scenarios
predictable
or
intelligent
responses.
Advanced Functional Materials,
Journal Year:
2025,
Volume and Issue:
unknown
Published: Feb. 26, 2025
Abstract
Auxetic
metamaterials
refer
to
materials
and
structures
with
extraordinary
deformation,
i.e.,
transverse
expansion
(contraction)
under
uniaxial
tension
(compression).
In
recent
decades,
a
very
wide
range
of
innovative
functional
performance
has
been
discovered
stemming
from
this
behavior.
This
desirable
exhibition
adaptivity,
programmability,
functionality
provides
great
potential
in
soft
intelligent
systems.
However,
thus
far,
the
mainstream
research
on
auxetic
focused
subjective
design,
monotonic
mechanical
properties,
passive
tunability.
review
thorough
overview
classical
properties
applications,
primary
objective
proposing
new
roadmap
auxetics
for
advances
interdisciplinary
field.
The
fundamental
works
are
categorized
different
configurations
mechanisms.
particular,
integration
shape
morphing,
actuation,
sensing,
multiphysical
response,
inverse
design
is
reviewed
detail.
To
accelerate
development
smart
structural
systems,
applications
generalized
into
robotics
(outside
body),
human–machine
interaction
(surrounding
healthcare
devices
(inside
body).
Finally,
several
significant
topics
emphasized
theory,
material
choice,
manufacturing
technique,
applications.
Advanced Materials,
Journal Year:
2023,
Volume and Issue:
36(9)
Published: Nov. 21, 2023
The
surge
in
advanced
manufacturing
techniques
has
led
to
a
paradigm
shift
the
realm
of
material
design
from
developing
completely
new
chemistry
tailoring
geometry
within
existing
materials.
Kirigami,
evolved
traditional
cultural
and
artistic
craft
cutting
folding,
emerged
as
powerful
framework
that
endows
simple
2D
sheets
with
unique
mechanical,
thermal,
optical,
acoustic
properties,
well
shape-shifting
capabilities.
Given
its
flexibility,
versatility,
ease
fabrication,
there
are
significant
efforts
kirigami
algorithms
create
various
architectured
materials
for
wide
range
applications.
This
review
summarizes
fundamental
mechanisms
govern
transformation
structures
elucidates
how
these
contribute
their
distinctive
including
high
stretchability
adaptability,
tunable
surface
topography,
programmable
shape
morphing,
characteristics
bistability
multistability.
It
then
highlights
several
promising
applications
enabled
by
designs
concludes
an
outlook
on
future
challenges
perspectives
kirigami-inspired
metamaterials
toward
real-world
Advanced Functional Materials,
Journal Year:
2023,
Volume and Issue:
33(36)
Published: May 14, 2023
Abstract
Rehabilitation
is
necessary
for
the
recovery
of
patients
with
paralysis
caused
by
stroke
and
muscle
atrophy.
Wearable
electronics
can
provide
feedback
on
physical
training
facilitate
healthcare.
However,
most
existing
wearable
are
difficult
to
maintain
a
conformal
skin‐device
interface.
Additionally,
use
non‐degradable
electronic
materials
associated
environmental
risks.
Herein,
ionogels
biodegradation
shape‐memory
properties
as
eco‐friendly
geometry‐adaptive
rehabilitation
proposed.
The
enabled
incorporating
polycaprolactone
segments
into
ionogel
matrix.
Moreover,
ionogel‐based
be
certain
joints
shape
programming,
stable
reproducible
real‐time
signals
reflecting
joint
movements
during
long‐term
assisted
robotic
glove,
facilitating
carers
assess
efficacy
choose
an
appropriate
scheme.
This
study
demonstrates
potential
biodegradable
green
adaptive
robot‐assisted
rehabilitation.
ACS Applied Materials & Interfaces,
Journal Year:
2023,
Volume and Issue:
15(15), P. 19190 - 19198
Published: April 7, 2023
Auxetic
kirigami
metamaterials
(KMs)
attain
negative
Poisson's
ratios
with
periodic
slender
cuts
on
thin
sheets.
The
existing
auxetic
KMs
forfeit
auxeticity
under
large
tensions
because
their
mainly
arises
from
in-plane
deformation,
but
out-of-plane
buckling
could
arise
to
cause
deviations,
and
thicker
would
suffer
stress
failure.
This
paper
proposes
a
novel
family
of
that
can
realize
retain
for
up
0.50
applied
strains
by
fully
exploiting
in
the
design
model.
Numerical
experimental
results
show
designed
possess
unique
properties
are
not
exhibited
KMs,
including
wide
range
designable
variation
modes
different
strains,
sheet
thickness-insensitive
auxeticity,
excellent
shape
recoverability.
A
potential
application
is
exemplified
scenario
they
as
stretchable
display
without
image
distortions
tensions.
proposed
open
new
opportunities
specific
functional
devices
areas
compliant
robotics,
bio-medical
devices,
flexible
electronics.
Materials & Design,
Journal Year:
2024,
Volume and Issue:
241, P. 112913 - 112913
Published: April 2, 2024
This
research
presents
the
design,
manufacturing,
and
macroscopic
characterization
of
flexible
mechanical
metamaterials
with
tunable
elastic
properties.
The
constants
were
given
using
energy
principle
Castigliano's
second
theorem,
results
validated
through
static
simulations
tensile
experiments,
showing
good
agreement.
Then
complete
parametric
study
was
conducted
to
demonstrate
possibility
extensively
customizing
Poisson
effect
stiffness.
Additionally,
comparison
between
developed
star-shaped
cellular
structures
on
properties
six
groups
samples.
demonstrated
that
exhibited
remarkable
superiority
in
deformability,
sensitivity,
auxeticity.
Furthermore,
an
innovative
experiment
is
devised
characterize
responses
coupling
system
complemented
numerical
modeling,
similar
phenomenon
also
observed
other
metamaterials.
proposed
design
offered
a
way
induce
system's
profile
occurring
wavy
deformation.
Advanced Functional Materials,
Journal Year:
2024,
Volume and Issue:
unknown
Published: Oct. 9, 2024
Abstract
Robotic
skins
that
integrate
artificial
tactile
sensing
elements
can
substantially
complement
the
perception
dimension
of
social
robots,
presenting
an
indispensable
part
in
human‐robot
interaction
(HRI).
However,
existing
design
frameworks
compromise
between
versatility
and
sustainability
due
to
restricted
range
characteristics
available
for
a
single
constituent.
Here
alterable
robotic
skin
constructed
from
homogeneous
units
are
proposed,
capable
cyclically
realtering
their
inherent
across
wide
spectrum.
Necessary
achieve
positioning
pressure
subunits
be
encoded
feature
motifs
extracted
through
condition‐induced
differentiation,
showcasing
remarkable
resemblance
gene
expression
living
system.
By
virtue
this,
up
100‐fold
differences
parameters
achieved,
including
modulus,
surface
state,
conductivity,
drive
target
attribute
coupling.
The
trans‐temporal
reconstruction
materials
enables
superb
customization
functional
building
blocks,
advancing
flexible
separation
combination
different
touch
modes,
location,
pressure,
duration,
motion
pattern.
As
proof
concept,
is
demonstrated
integrates
position‐sensing
layer
pressure‐sensing
layer.
It
accurately
distinguish
recognize
multi‐dimensional
motions
based
on
less‐channel
data,
which
showcases
efficient
haptic
application.
