Summary
The performance of a combination of two spherical pendulum vibration absorbers (SPVAs) to suppress the vibrations of a two-degree-of-freedom structure subjected to a unidirectional, horizontal, and harmonic excitation is theoretically investigated. The equations of motion of the system are expressed using new coordinates to prevent singularities at the zero inclination of the SPVAs. Van der Pol’s method is employed to determine the frequency response curves. Although the structure is excited in one direction by an external force, the structure and SPVAs exhibit whirling motions that depend on the excitation frequency. Localization of the two SPVAs may occur in specific ranges of excitation frequencies. The performances of the two SPVAs are evaluated and compared with those of a single SPVA.
