Self-Adaptive Electromechanical Metamaterials

This grant will support research on nonlinear vibrations and wave propagation to enable the development of new multi-functional metamaterial devices, thus promoting both the progress of science and advancing national prosperity. Metamaterials are artificially engineered materials used to manipulate and control sound, light, and many other physical phenomena.

These materials have proven to be useful in many applications such as ultrasonic, vibration mitigation, energy harvesting, and sensing (e.g., complex filtering, light channeling). However, most mechanical energy control devices currently available operate in a narrow frequency range and cannot adapt to changing frequency. This award will support fundamental research to provide needed knowledge for the design and fabrication of self-adaptive metamaterials that can achieve a wide frequency self-tuning range.

The new self-adaptive metamaterial can be easily integrated into various engineering structures (e.g., automotive or aircraft components) to enable low-cost and reliable vibration mitigation, energy harvesting, and sensing techniques. Other systems and applications that will also benefit from this research include absorbers for wind-induced vibration control, as well as self-powered sensors for real-time monitoring of gas turbines and civil infrastructure.

The broader impacts of the project include inclusion of students from underrepresented groups, mentoring and training of undergraduate and graduate students, and integration of the research findings in classroom materials.

The self-adaptive metamaterial will be designed using the concept of passive self-tuning via a sliding mass, and quasiperiodic arrangements of the local resonators. The primary objective of this research is to gain fundamental understanding of the nonlinear dynamic interactions within such an electromechanical metamaterial. The secondary objective is to test the hypothesis that the interplay between quasiperiodic arrangements and self-tunability in metamaterials can improve the performance of vibration mitigation and energy harvesting or sensing.

To address this problem, the research team will conduct a combination of theoretical, computational, and experimental analyses. Quasiperiodicity in the local resonators will be examined for the purpose of realizing tunable-topological bandgaps. The team will investigate how localized topologically protected modes can be harnessed to improve energy harvesting and sensing while conserving vibration mitigation performance.

Prototypes of the self-adaptive metamaterial will be fabricated, and rigorous experiments will be conducted to validate and refine the theoretical development. It is anticipated that the self-adaptive metastructure will provide unprecedented performance characteristics for a wide range of engineering applications.

This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.