Design of Nonlinear Energy Sink Based on Bistable Cosine-Shaped Beam

To achieve high attenuation to environment vibration and noise, a new kind of nonlinear energy sink (NES) is proposed by incorporating a bistable cosine-shaped beam connected to a cantilever. The dynamic model of the NES is established by depicting the nonlinear stiffness of the bistable beam to be a cubic function. The vibration attenuation efficiency of the newly proposed NES is analyzed by solving the nonlinear dynamic equations with Runge-Kutta method. A NES prototype is fabricated and the experimental results adequately validated the effectiveness of the proposed nonlinear energy sink. It is shown that the nonlinear energy sink can reduce the main system response by 30% compared with the situation before the bifurcation.