A Beam-Type Nonlinear Dynamic Vibration Absorber

Nonlinear dynamic vibration absorbers have been extensively utilized for controlling vibrations in structures. A beam-type nonlinear dynamic vibration absorber (BNDVA) is proposed and investigated. A nonlinear dynamic model of the coupled single-degree-of-freedom system is established to systematically evaluate its vibration suppression performance. First, the effects of excitation amplitude on vibration reduction efficiency, effective suppression bandwidth, and oscillator’s response characteristics are examined through theoretical analysis. The effects of nonlinear parameters on the efficiency of vibration suppression and the response of the oscillator are examined. It is shown that a relatively high vibration reduction efficiency can be maintained under different excitation conditions, while a non-monotonic variation is observed with increasing excitation amplitude. The nonlinear effect is shown to effectively suppress the oscillator’s response and broaden the high-frequency operating range. Meanwhile, a mathematical model is constructed using machine learning. The model maps vibration reduction efficiency and nonlinearity performance index in the parameter space of excitation amplitude and primary system frequency. Rapid prediction of performance and identification of effective vibration reduction regions are achieved. Finally, an experimental platform is established, and the absorber’s performance under different excitation amplitudes is tested. The experimental results agreed closely with theoretical results. The reliability of the theoretical analysis is effectively validated by the experimental results. The proposed theoretical and machine learning models provide a systematic basis and experimental reference for the performance evaluation, design optimization, and engineering application of nonlinear vibration absorbers.