An illustration of the novel self-conscious metamaterial system as used in a coronary artery stent. The design can detect restenosis when used in a stent, and the same design can be used on a large scale in bridge girders to self-monitor the structure for defects.
iSMaRT laboratory
From the largest bridges to the smallest medical implants, sensors are everywhere, and for good reason: The ability to detect and monitor changes before they become problems can be both cost-effective and life-saving.
To better address these potential threats, the Intelligent Structural Monitoring and Response Testing (iSMaRT) Lab at the University of Pittsburgh Swanson School of Engineering has developed a new class of materials that are both sensor media and nanogenerators that will revolutionize the multifunctional technology big and small.
The research recently published in Nano Energy describes a new metamaterial system that acts as its own sensor, recording and relaying important information about the pressure and stresses on its structure. The so-called “self-conscious metamaterial” generates its own power and can be used for a variety of sensing and monitoring applications.
The most innovative facet of the work is its scalability: the same design works in both the nano and the mega range by simply adjusting the design geometry.
“There is no doubt that next-generation materials need to be multifunctional, adaptable and tunable.” said Amir Alavi, Assistant Professor of Civil, Environmental and Bioengineering who runs the iSMaRT Lab. “You cannot achieve these properties with natural materials alone – you need hybrid or composite material systems where each individual layer offers its own functionality. The confident metamaterial systems we invented can provide these properties by using advanced metamaterial and energy harvesting technologies at multiple levels, be it a medical stent, a shock absorber, or an airplane wing. “
While almost all existing self-recognizing materials are composites based on various forms of carbon fiber as sensor modules, this new concept offers a completely different, yet efficient approach to the production of sensor and nanogenerator material systems. The proposed concept is based on a performance-based design and the assembly of material microstructures.
The material is designed in such a way that contact electrification occurs between its conductive and dielectric layer under pressure, creating an electrical charge that transmits information about the state of the material. In addition, it naturally inherits the excellent mechanical properties of metamaterials, such as negative compressibility and ultra-high resistance to deformation. The electricity generated by its built-in triboelectric nanogenerator mechanism eliminates the need for a separate power source: such material systems can use hundreds of watts of power on a large scale.
A game changer, from the human heart to space habitats
“We believe that this invention will fundamentally change metamaterial science, where multifunctionality is now becoming a major factor,” said Kaveh Barri, lead author and PhD student in Alavi’s laboratory. “While a substantial part of the current efforts in this area is only directed towards the exploration of new mechanical properties, we go a step further by introducing revolutionary self-charging and self-awareness mechanisms into the tissue of material systems.”
“Our most exciting contribution is that we bring new aspects of intelligence into the texture of metamaterials. We can literally turn any material system into sensor media and nanogenerators with this concept, ”added Gloria Zhang, co-lead author and PhD student at Alavi’s laboratory.
Researchers have created several prototype designs for a variety of civil, aerospace, and biomedical engineering applications. On a smaller scale, a cardiac stent of this design can be used to monitor blood flow and detect signs of restenosis or re-narrowing of an artery. The same design was also used on a much larger scale to create a mechanically tunable beam suitable for a bridge that can itself monitor for defects in its structure.
These materials also have enormous potential beyond the earth. A confident material doesn’t use carbon fiber or coils; it is low in mass, low in density, low in cost, high in scalability, and can be made using a wide range of organic and inorganic materials. These properties make them ideal for use in future space research.
“To fully understand the enormous potential of this technology, imagine how we can even adapt this concept to build structurally sound self-sufficient space habitats using only indigenous materials on Mars and beyond. We’re actually investigating this right now, ”said Alavi. “With this concept you can create nano-, micro-, macro- and mega-scale material systems. Therefore I am confident that this invention can form the basis for a new generation of technical living structures that react to external stimuli and monitor their condition themselves. ” , and propel yourself. “
– This press release was originally posted on the University of Pittsburgh Swanson Engineering website. It was edited for style
Comments are closed.