Programmable structures from the printer
Date:
July 9, 2021
Source:
University of Freiburg
Summary:
Research team develops new method for 3D-printing materials systems
that move like a climbing plant.
FULL STORY ========================================================================== Researchers at the University of Freiburg and the University of Stuttgart
have developed a new process for producing movable, self-adjusting
materials systems with standard 3D-printers. These systems can undergo
complex shape changes, contracting and expanding under the influence
of moisture in a pre-programmed manner. The scientists modeled their development based on the movement mechanisms of the climbing plant known
as the air potato (Dioscorea bulbifera).
With their new method, the team has produced its first prototype:
a forearm brace that adapts to the wearer and which can be further
developed for medical applications. This process has been collaboratively developed by Tiffany Cheng and Prof. Dr. Achim Menges from the Institute
of Computational Design and Construction (ICD) and the Integrative Computational Design and Construction for Architecture Cluster of
Excellence (IntCDC) at the University of Stuttgart, together with
Prof. Dr. Thomas Speck from the Plant Biomechanics Group and the Living, Adaptive and Energy-autonomous Materials Systems Cluster of Excellence (livMatS) at the University of Freiburg. The researchers are presenting
their results in the journal Advanced Science.
========================================================================== 4D-printing defines shape changes 3D-printing has established itself as
a manufacturing process for a wide range of applications. It can even be
used to produce intelligent materials and material systems that remain in motion after printing, autonomously changing shape from external stimuli
such as light, temperature or moisture. This so- called '4D-printing',
in which predetermined shape changes can be triggered by a stimulus,
immensely expands the potential applications of material systems.
These changes in shape are made possible by the chemical composition of
the materials, which consist of stimuli-responsive polymers. However,
the printers and base materials used to produce such materials systems
are usually highly specialized, custom-made and expensive -- until now.
Now, using standard 3D-printers, it is possible to produce materials
systems that react to changes in moisture. Given their structure, these materials systems can undergo shape changes in the entire system or
simply in the individual parts. The researchers at the Universities of
Freiburg and Stuttgart combined multiple swelling and stabilizing layers
to realize a complex movement mechanism: a coiling structure that pulls
tighter by unfolding 'pockets' as pressors and which can loosen up again
on its own when the 'pockets' release and the coiled structure returns
to the open state.
Natural movement mechanisms transferred to technical material systems
For this new process, the scientists used a mechanism from nature: the
air potato climbs trees by applying pressure to the trunk of the host
plant. To do this, the plant first winds loosely around a tree trunk. Then
it sprouts 'stipules', basal outgrowths of the leaves, which increase the
space between the winding stem and the host plant. This creates tension
in the winding stem of the air potato. To imitate these mechanisms,
the researchers constructed a modular material system by structuring
its layers so that it can bend in different directions and to different degrees, thereby coiling and forming a helix structure. 'Pockets' on
the surface cause the helix to be pushed outwards and put under tension, causing the entire material system to contract.
"So far, our process is still limited to existing base materials that
respond to moisture," says Achim Menges. "We're hoping," Thomas Speck
adds, "that in the future, inexpensive materials that also respond to
other stimuli will become available for 3D-printing and can be used
with our process." Living, Adaptive and Energy-autonomous Materials
Systems Cluster of Excellence (livMatS) Researchers at the University
of Freiburg's Living, Adaptive and Energy- autonomous Materials Systems
Cluster of Excellence (livMatS) are developing life-like materials
systems that are inspired by nature. Like living structures they
adapt autonomously to different environmental factors, generate clean
energy from their environment and are impervious to damage or can heal themselves. Nevertheless these materials systems will be purely technical objects, so they can be produced using synthetic methods and deployed
in extreme conditions. Thomas Speck is a member of the team of speakers
at the Cluster of Excellence.
========================================================================== Story Source: Materials provided by University_of_Freiburg. Note:
Content may be edited for style and length.
========================================================================== Journal Reference:
1. Tiffany Cheng, Marc Thielen, Simon Poppinga, Yasaman Tahouni,
Dylan Wood,
Thorsten Steinberg, Achim Menges, Thomas Speck. Bio‐Inspired
Motion Mechanisms: Computational Design and Material Programming
of Self‐Adjusting 4D‐Printed Wearable Systems. Advanced
Science, 2021; 8 (13): 2100411 DOI: 10.1002/advs.202100411 ==========================================================================
Link to news story:
https://www.sciencedaily.com/releases/2021/07/210709094459.htm
--- up 9 weeks, 22 hours, 45 minutes
* Origin: -=> Castle Rock BBS <=- Now Husky HPT Powered! (1:317/3)