Dynamic excitations in periodic fish scale inspired structures

Fish scale-like structures on substrates, arranged periodically, work together to create unique mechanical and optical behaviors. These include nonlinear stiffness, anisotropic deformation, and eventually, locking behavior. Fabrication of scale-like biomimetic examples involves embedding stiffer, plate-like sections into softer substrates. Previously, research has focused on their static qualities. The dynamic response is just as fascinating, showing remarkable interplay between geometry and materials, along with anisotropies. The damping behavior observed here significantly diverges from the conventional damping seen in mechanical frameworks, often modeled as Rayleigh damping. Here we discuss the origin of some of these behaviors that include material-geometry distinction in damping, multiple damping modes and interplay of dissipation possibilities. We have shown a derivation of simple mathematical laws estimating nonlinear spring damper system that govern architecture-dissipation relationships and can help guide design. We conclude by noting the different type of structural damping with other forms of dissipation typically encountered in mechanical behavior.