Meccanica Magazine n. 4

ENG
The SMARTEX project winner of the second edition of the “Call for
Researchers”
The “Call for Researchers” initiative of the Department of Mechanical
Engineering is now in its second year. It is a competitive call for
which the candidate, also the scientific director of the project,
must choose a research topic and pick a research team to bring
diverse skills to the table. Interdisciplinarity is the main application
requirement as the goal is to make researchers from different DMEC
Research Lines cooperate while involving other Italian and foreign
Universities.
For the 2021 edition, our researchers were asked to submit research
projects related to the Sustainable Development Goals (SDGs). The
Evaluation Committee received five research proposals coordinated
by: Stefano Arrigoni presenting the “Intelligent Transportation
Services for POLIMI (IT4POLIMI)” project, Niccolò Beccattini
presenting the “Manta Ray-inspired microplastics filtration unit
for domestic and industrial applications (MANTRA)” project, Dayou
Ma presenting the “Development of Stochastic Numerical Model
for Quality Design of Nanocomposites (SIMONE)” project, Luca
M. Martulli presenting the “Structural sMARt fabric with TunablE
properties (SMARTEX)” project e Paolo Schito presenting the
“COACHING FOR RTDx (COACH)” project.
According to the criteria indicated in the call, the Committee
appointed the SMARTEX project as the winner. Congratulations to
Luca and sincere thanks to all the researchers who participated in
the competition.
“I think that the underlying objective of the “Call for Researchers”
is to allow young researchers to create new networks within
the Department of Mechanical Engineering. This was especially
important to me, since I joined Polimi only in November 2020”
declared the scientific director of SMARTEX, Luca M. Martulli,
winner of the last edition of the Call for Researchers issued by the
Department of Mechanical Engineering within the Dipartimento di
Eccellenza project LIS4.0.
The research object of the SMARTEX projects are smart fabrics
are textile-like structures capable of responding to environmental
stimuli. Most of the research and industrial efforts is currently
focused to the development of smart fabrics that implement
electronic features; these so called “e-textiles” have been
traditionally used as sensors in medical devices, wearable
electronics and energy harvesting applications. Only little effort
was spent in the possibility of prototyping Structural Smart Fabrics
(SSFs), namely smart fabrics with tunable mechanical properties.
This is in contrast with the clear need for smart materials featuring
variable mechanical properties, witnessed by the development of
technologies like 4D printing or shape memory materials. SSFs are
textile-like structures that can be geometrically and functionally
optimised thanks to the advent of 3D additive manufacturing
which enables to produce chainmail-like fabrics. One of the main
potentials of these structures is the possibility to adopt interlocked
discrete cells, opening new possibilities in creating stiffnesstailored
fabrics. To enhance these properties, functional materials
such as Shape Memory Alloys (SMAs) can be used thanks to their
capability to mechanically react under external stimuli. Potential
applications for SSFs extend to lightweight space structures, soft
robots, medical devices and more. SMA actuated SSFs will thus
broaden the possible applications of smart fabrics, providing them
with the capability
to adapt to variable functional specifications in terms of shape and
stiffness.
Within this context, the SMARTEX project aims to advance the
current state of the art on smart fabrics by designing, manufacturing
and testing an SSF actuated by SMAs. SMARTEX will make extensive
use of additive manufacturing techniques, which makes it fully
compliant with the needs of the Industry 4.0. Moreover, the use of
SMAs as actuating devices will make the SMARTEX fabric sensitive
to temperature or to an electric current as signal.
SMARTEX will therefore be a 3D printed chainmail-like SSF
responsive to temperature thanks to the assembly with SMA
actuation devices. In this regard, SMARTEX can be seen as a
hybrid structure made by two components. At room temperature,
being the SMA device in its soft condition, SMARTEX will be in its
“inactive” state. SMARTEX will have a near-zero bending stiffness
and thus behave as a standard fabric, being flexible enough to be
folded or bent. At high temperatures, SMARTEX will be in its “active”
configuration: the SMA device will activate, jamming all the fabric
cells between each other. The bending stiffness of SMARTEX will
thus significantly increase, behaving more similarly to a plate and
being capable of carrying loads.
While the SMARTEX project does not focus on a specific application,
it will develop an extremely versatile new smart fabric with unique
properties and its dedicated design approach. The developed fabric
is thus expected to have a vast range of applications, like soft
robotics, space components, support for heat shields, biomedical
devices and more.
“Thanks to this call – continued the young scientific director
Martulli - I was able to meet the members of what later became the
SMARTEX team: Luca Patriarca, Paolo Parenti, Marco Rossoni and
myself. Together, we form a multidisciplinary team, with expertise
including experimental mechanics, analytical and numerical
modelling, composite materials, Shape Memory Alloys, 3D printing,
virtual prototyping and more. These are all key ingredients in the
development of an innovative type of smart fabrics”.
meccanica magazine
95