Structural vibration absorption in multilayered sandwich structures using negative stiffness nonlinear oscillators

We hereby report on the incorporation of negative stiffness oscillators realized through Euler buckled beams within vibrating multilayered sandwich structures. Such devices have been extensively investigated as single degree of freedom isolation mechanisms when mechanical grounding is available. It is worth exploring the influences of implementing such mechanisms within continuous multilayered vibrating structures given their interesting nonlinear vibration isolation characteristics. A numerical investigation is presented in this work with the computed performance being compared against the one of linear oscillators of equal mass and damping properties. Despite the fact that the negative stiffness nonlinear (NSN) oscillators were not properly optimized for the specific application due to the implied computational cost, they exhibited superior performance to their linear counterparts in a broadband sense. Considering the dependence of the linear resonators’ performance to manufacturing precision and narrowband excitation, the NSN concept is an excellent candidate for attenuating structural vibration across a wide spectrum.