While working, mechanical devices and structures are exposed to vibration. This vibration, caused by moving parts or generation elements, is usually redundant and even destructive. At the last years, the Nonlinear Energy Sink (NES) was invented as a prospective solution to this problem. The NES devices are essentially nonlinear and relatively small mass systems which are attached to the main structure and irreversibly pump energy outwards and by dissipation vanish the energy they absorbed. The mechanism of navigating the residual energy one-directionally into the NES is called Targeted Energy Transfer (TET). Current work is devoted to applicability of common pendulum as the NES for mitigation of impulsive excitations. It turns out that if the pendulum is tuned at linear frequency of the primary mass, it can overcome one of main shortcomings of traditional NES designs and efficiently absorb energy in a wide range of energies. The reason is that for small energies the pendulum responds as tuned mass damper; at higher energies the pendulum acts as rotational NES. Thus, relatively broad diapason of energies can be covered. The model of the eccentric NES is presented in Figure 1.
We demonstrate numerically that the properly tuned pendulum can be used as the NES and indeed has broader energy range than regular rotational NES. We discuss the relationship between the pendulum NES performance and variation of its initial conditions, as one can see in Figure 2 - the mean time for sufficient energy absorbance and its standard deviation for different values of initial energy, given by different values of initial conditions, with account of the gravity.
