Figure : the concept of the proposalmeccanica magazine94
ENGThe SMARTEX project winner of the second edition of the “Call forResearchers”The “Call for Researchers” initiative of the Department of MechanicalEngineering is now in its second year. It is a competitive call forwhich the candidate, also the scientific director of the project,must choose a research topic and pick a research team to bringdiverse skills to the table. Interdisciplinarity is the main applicationrequirement as the goal is to make researchers from different DMECResearch Lines cooperate while involving other Italian and foreignUniversities.For the 2021 edition, our researchers were asked to submit researchprojects related to the Sustainable Development Goals (SDGs). TheEvaluation Committee received five research proposals coordinatedby: Stefano Arrigoni presenting the “Intelligent TransportationServices for POLIMI (IT4POLIMI)” project, Niccolò Beccattinipresenting the “Manta Ray-inspired microplastics filtration unitfor domestic and industrial applications (MANTRA)” project, DayouMa presenting the “Development of Stochastic Numerical Modelfor Quality Design of Nanocomposites (SIMONE)” project, LucaM. Martulli presenting the “Structural sMARt fabric with TunablEproperties (SMARTEX)” project e Paolo Schito presenting the“COACHING FOR RTDx (COACH)” project.According to the criteria indicated in the call, the Committeeappointed the SMARTEX project as the winner. Congratulations toLuca and sincere thanks to all the researchers who participated inthe competition.“I think that the underlying objective of the “Call for Researchers”is to allow young researchers to create new networks withinthe Department of Mechanical Engineering. This was especiallyimportant 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 theDepartment of Mechanical Engineering within the Dipartimento diEccellenza project LIS4.0.The research object of the SMARTEX projects are smart fabricsare textile-like structures capable of responding to environmentalstimuli. Most of the research and industrial efforts is currentlyfocused to the development of smart fabrics that implementelectronic features; these so called “e-textiles” have beentraditionally used as sensors in medical devices, wearableelectronics and energy harvesting applications. Only little effortwas 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 featuringvariable mechanical properties, witnessed by the development oftechnologies like 4D printing or shape memory materials. SSFs aretextile-like structures that can be geometrically and functionallyoptimised thanks to the advent of 3D additive manufacturingwhich enables to produce chainmail-like fabrics. One of the mainpotentials of these structures is the possibility to adopt interlockeddiscrete cells, opening new possibilities in creating stiffnesstailoredfabrics. To enhance these properties, functional materialssuch as Shape Memory Alloys (SMAs) can be used thanks to theircapability to mechanically react under external stimuli. Potentialapplications for SSFs extend to lightweight space structures, softrobots, medical devices and more. SMA actuated SSFs will thusbroaden the possible applications of smart fabrics, providing themwith the capabilityto adapt to variable functional specifications in terms of shape andstiffness.Within this context, the SMARTEX project aims to advance thecurrent state of the art on smart fabrics by designing, manufacturingand testing an SSF actuated by SMAs. SMARTEX will make extensiveuse of additive manufacturing techniques, which makes it fullycompliant with the needs of the Industry 4.0. Moreover, the use ofSMAs as actuating devices will make the SMARTEX fabric sensitiveto temperature or to an electric current as signal.SMARTEX will therefore be a 3D printed chainmail-like SSFresponsive to temperature thanks to the assembly with SMAactuation devices. In this regard, SMARTEX can be seen as ahybrid 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 stiffnessand thus behave as a standard fabric, being flexible enough to befolded or bent. At high temperatures, SMARTEX will be in its “active”configuration: the SMA device will activate, jamming all the fabriccells between each other. The bending stiffness of SMARTEX willthus significantly increase, behaving more similarly to a plate andbeing 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 uniqueproperties and its dedicated design approach. The developed fabricis thus expected to have a vast range of applications, like softrobotics, space components, support for heat shields, biomedicaldevices and more.“Thanks to this call – continued the young scientific directorMartulli - I was able to meet the members of what later became theSMARTEX team: Luca Patriarca, Paolo Parenti, Marco Rossoni andmyself. Together, we form a multidisciplinary team, with expertiseincluding experimental mechanics, analytical and numericalmodelling, composite materials, Shape Memory Alloys, 3D printing,virtual prototyping and more. These are all key ingredients in thedevelopment of an innovative type of smart fabrics”.meccanica magazine95