Experimental and Theoretical Analysis of Vibration Reduction of a Nonlinear Energy Sink With Piecewise Linear Stiffness

Abstract The vibration reduction problem of a nonlinear energy sink (NES) with piecewise linear stiffness is investigated in this work. The NES can effectively assist in vibration reduction of the primary system, while piecewise linear stiffness can effectively enhance the damping effect and control vibration of the NES. An experimental setup for the NES system with piecewise linear stiffness is designed, and control equations are established using the Newton's Second Law. Based on experimental data, system parameters are obtained, and the steady-state response of the system is calculated using the incremental harmonic balance (IHB) method. Through stability analysis, the existence of quasi-periodic and chaotic responses in the system's vibration response are discovered. The results obtained from the IHB method are validated using numerical method and experimental studies, showing good accuracy. The energy absorption efficiency of the NES with piecewise linear stiffness is discussed, and effects of different parameters of the NES on the system are studied in detail to optimize the performance of the NES. Results indicate that nonlinear stiffness and piecewise linear stiffness, along with controlling a certain value of the NES damping and mass, can achieve better vibration control.