The Implementation of an Adaptive Electromagnetic Active Vibration Absorber for Multi-frequency Broadband Vibration Control

Purpose: Multi-frequency vibration is challenging to control owing to the presence of multiple harmonic frequency components within a broad frequency band. This work aims to develop an adaptive electromagnetic active vibration absorber specifically designed for multi-frequency broadband vibration suppression. Methods: The work begins by establishing the structure and dynamic model of the proposed active absorber. Two optimization objectives suitable for the dynamic output force are presented, and structural optimization design is then performed. To overcome the limitations of the filtered-x least mean square (FxLMS) algorithm in damping multiple narrowband disturbances, an improved adaptive control approach is proposed based on the discrete wavelet transform (DWT) algorithm and reference signal self-reconstruction technique. Results: Experimental results demonstrate that the vibration responses at the natural frequency as well as under multi-frequency excitation can be rapidly and significantly attenuated. The effectiveness and superiority of the proposed adaptive AVA are experimentally validated. Conclusion: An adaptive active control system that integrates the DWT algorithm and the reference signal self-reconstruction technique can achieve the suppression of multi-frequency harmonic excitations with unknown disturbances or sources within a broad frequency band through frequency division control.