Experimental and Numerical Investigation on Bistable Locally Resonant Elastodynamic Metamaterials

While metamaterials are primarily associated with negative refractive indices and invisibility cloaking in electromagnetism or optics, the deceptively simple metamaterial concept also applies to somewhat different areas such as classical mechanics, including acoustics and elastodynamics. Along these lines, the research work presented here focuses on bistable locally resonant elastodynamic metamaterials (LRMs) designed for ultra-low frequency wave attenuation. With the development of rapid and affordable prototyping by means of additive manufacturing, the study included an experimental activity that highlighted the importance of system identification. The rich and complex dynamics of bistability required vast amounts of analyses and careful modelling. Therefore, the strong nonlinearity and rapidly varying dynamics resulted in system identification beyond conventional methods.