Browse Topic: Smart materials
For sustainability reasons, the automotive market is requesting 100% monomaterial noise treatments, particularly for the end-of-life recycling without any part separation operation. But also, OEMs require super light, highly performance insulating noise treatments for electric vehicles in order to extend vehicle autonomy. PP melt-blown fiber felts present good mono-material characteristics with very good absorption, but generally not so good insulation properties behind an airtight barrier due to lack of stiffness. Moreover, these PP melt-blown fiber felts are relatively expensive and not thermoformable, thus forcing them to be used as 2D die-cut parts behind existing hard or soft trims classically. The shown optimization approach proposes to return to 100% thermoformable recycled and recyclable PET formulations blending unusual coarse mechanical specific fibers, in order to optimize the viscothermal exchanges, while maintaining good mechanical properties, with microfibers for best dissipation properties bonded by bi-component fibers. The insulation properties obtained as poroelastic spring behind a barrier allow a weight reduction of -50% compared to cotton felt while being 1 dB better for the Insertion Loss values (2 dB compared to a flexible foam) and perform as well as best PP melt-blown fiber felts while being more competitive as well as thermoformable. It is possible to adjust the sound insulation properties, sound absorption and hardness (static compressibility) using optimal PET fibers formulations but also thanks to felt verticalization processes. These optimization levers will be illustrated in this paper.
Healable spacecraft structures could soon be possible thanks to cutting-edge composite technology. Swiss companies CompPair and CSEM, and Belgian company Com&Sens have partnered with the European Space Agency (ESA) to modify their self-healing carbon fiber product for use in space transportation.
Bioelectronics, such as implantable health monitors or devices that stimulate brain cells, are not as soft as the surrounding tissues due to their metal electronic circuits. A team of scientists has developed a soft polymer hydrogel that can conduct electricity as well as metal can. As the material is both flexible and soft, it is more compatible with sensitive tissues. This finding has the potential for a large number of applications, for example, in biocompatible sensors and in wound healing.
EPFL researchers have engineered a fiber-based electronic sensor that remains functional even when stretched to over 10 times its original length. The device holds promise for smart textiles, physical rehabilitation devices, and soft robotics.
Researchers from Harbin Institute of Technology and their collaborators have developed a multifunctional polyelectrolyte hydrogel reinforced with aramid nanofibers (ANFs) and MXene nanosheets, achieving outstanding performance in absorption-dominated electromagnetic interference (EMI) shielding and wearable sensing. This innovative hydrogel addresses the long-standing challenge of balancing electrical conductivity and effective EMI absorption in flexible electronic materials. The research was published in the journal Nano-Micro Letters. 1
The activation of the fuel injector affects both engine performance and pollutant emissions. However, the automotive industry restricts access to information regarding the circuits and control strategies used in its vehicles. One way to optimize fuel injections is using piezoelectric injectors. These injectors utilize crystals that expand or contract when subjected to an electric current, moving the injector needle. They offer a response time up to four times faster than solenoid-type injectors and allow for multiple injections per combustion cycle. These characteristics result in higher combustion efficiency, reduced emissions, and lower noise levels, making piezoelectric injectors widely used in next-generation engines, where stricter emission and efficiency standards are required. This study aims to design a drive circuit for piezoelectric injectors in a common rail system, intended for use in a diesel injector test bench. Experimental measurement of voltage was obtained from an injector coupled to a running diesel engine. The developed equivalent circuit demonstrated the capability to drive piezoelectric injectors with voltage values close to those observed in a commercial injector installed in a diesel engine, validating its suitability for research and experimental applications. Additionally, injector operating curves were generated, evaluating the injected diesel mass flow rate for different energization times and injection pressure. The designed equivalent circuit successfully enabled the correct operation of piezoelectric injectors on the test bench, reproducing the expected charge and discharge behavior required for precise actuation.
Researchers are testing a new technology that incorporates shape memory material for clear plastic dental aligners, an alternative to traditional metal braces. The clear aligners still need to be improved to the point that there are two materials — clear aligners and metal braces — that are as good as each other.
New research studying shape memory alloys with AI may allow fighter jets to transform into the future with the help of new materials. Texas A&M University, College Station, TX In aerospace applications, high-temperature shape memory alloys (HTSMAs) - materials capable of remembering and returning to their original shapes after heating - are often constrained by high costs since they rely on expensive elements to function at elevated temperatures. Fighter jets like the F/A-18 need to fold their wings to fit on crowded aircraft carriers. The system that folds the wings relies on heavy mechanical parts. But with new lighter, smarter alloys, those movements could be done with less weight and more efficiency. That means more jets can be ready to fly, faster and with less energy wasted.
In aerospace applications, high-temperature shape memory alloys (HTSMAs) — materials capable of remembering and returning to their original shapes after heating — are often constrained by high costs since they rely on expensive elements to function at elevated temperatures.
University of California San Diego and CEA-Leti scientists have developed a ground-breaking piezoelectric-based DC-DC converter that unifies all power switches onto a single chip to increase power density. This new power topology, which extends beyond existing topologies, blends the advantages of piezoelectric converters with capacitive-based DC-DC converters.
A study led by Tohoku University, Iwate University, The Japan Aerospace Exploration Agency (JAXA), National Astronomical Observation of Japan, Tokyo City University, and Kyoto University developed a novel copper-based alloy that exhibits a special shape memory effect at temperatures as low as -200 °C. Shape memory alloys can be deformed into different shapes when cold, but will revert back to their original shape when heated (as if “remembering” their default state, like memory foam). This exciting new alloy has the potential to be used for space equipment and hydrogen-related technologies, where challenging, cold environments below -100 °C are the norm.
A new study analyzes the use of shape memory alloys in developing thermally driven actuators for spacecraft operating space exploration missions. Tohoku University, Sendai City, Japan A study led by Tohoku University, Iwate University, The Japan Aerospace Exploration Agency (JAXA), National Astronomical Observation of Japan, Tokyo City University, and Kyoto University developed a novel copper-based alloy that exhibits a special shape memory effect at temperatures as low as −200 °C. Shape memory alloys can be deformed into different shapes when cold, but will revert back to their original shape when heated (as if “remembering” their default state, like memory foam). This exciting new alloy has the potential to be used for space equipment and hydrogen-related technologies, where challenging, cold environments below −100 °C are the norm. Previously studied shape memory alloys using Ni-Ti could not maintain their shape memory ability below −20 °C, despite their otherwise practical characteristics. In contrast, the known existing shape memory alloys that can actually operate below −100 °C aren't suitable for practical implementation. This study met the challenge of finding the first functional actuator material capable of large work output at temperatures below −100 °C. Actuators are components that turn some sort of input into mechanical energy (movement). They can be found not only in machines bound for outer space, but in everyday devices all around us.
A team of UCLA engineers and their colleagues have developed a new design strategy and 3D printing technique to build robots in one single step. The breakthrough enabled the entire mechanical and electronic systems needed to operate a robot to be manufactured all at once by a new type of 3D printing process for engineered active materials with multiple functions (also known as metamaterials). Once 3D printed, a “meta-bot” will be capable of propulsion, movement, sensing, and decision-making.
Research engineers are developing smart implants that can both monitor and promote healing in fractured bones. When installed at the fracture site, these implants, which are constructed using shape memory alloys, can stiffen or relax in a continuously controlled manner that optimizes bone healing.
Researchers have developed a multifunctional sensor based on semiconductor fibers that emulates the five human senses. Prof. Bonghoon Kim, department of robotics and mechatronics engineering of Daegu Gyeongbuk Institute of Science & Technology (DGIST), conducted the study in collaboration with Prof. Sangwook Kim at KAIST, Prof. Janghwan Kim at Ajou University, and Prof. Jiwoong Kim at Soongsil University. The technology developed in the study is expected to be utilized in fields such as wearables, Internet of Things (IoT), electronic devices, and soft robotics.
Researchers have developed a three-dimensional stretchable piezoelectric energy harvester that can harvest electrical energy using body movements. The device is to be used as a wearable energy harvester as it can be attached to the skin or clothes.
Researchers have helped create a new 3D printing approach for shape-changing materials that are likened to muscles, opening the door for improved applications in robotics as well as biomedical and energy devices.
Researchers have successfully demonstrated the four-dimensional (4D) printing of shape memory polymers in submicron dimensions that are comparable to the wavelength of visible light. 4D printing enables 3D-printed structures to change their configurations over time and is used in a variety of fields such as soft robotics, flexible electronics, and medical devices.
Researchers have now developed the first hydrogel implant designed for use in fallopian tubes. This innovation performs two functions: one is to act as a contraceptive, the other is to prevent the recipient from developing endometriosis in the first place or to halt the spread if they do.
Items per page:
50
1 – 50 of 447