Resonance reduction of primary system using variable mass tuned vibration absorber

The conventional passive tuned vibration absorber (TVA) can substantially reduce the vibration of a primary system only when it is tuned to the excitation frequency. To overcome this narrow-band problem, some adaptive tuned vibration absorbers (ATVAs) were developed in recent years. ATVAs possess natural frequencies that can usually be adjusted by altering absorber stiffness. Another problem of this device is that using the TVA can result in the resonance of a primary system since a new composite system is formed when a TVA is attached to a primary system. In this paper, a novel control strategy based on variable mass (VM) ATVA is proposed to reduce the resonance of the primary system. Unlike previous designs, the natural frequency of the VM ATVA can be adjusted by changing its mass, and the control plan can be implemented in the same manner. A numerical simulation and some experiments were conducted to test the performance of the new control plan, and the results show that the suggested plan can achieve a resonance reduction of approximately 17.6 dB in the simulation and about 11.3 dB in the experimental system. This finding implies that the VM absorber that uses the proposed control plan can effectively suppress the vibration of a primary system over a wide frequency band and effectively reduce its resonance. Moreover, the new control strategy is actually a generalizable method that can be used on other types of ATVA.