Excitation of vertical biharmonic oscillations via the phenomenon of self-synchronization

The possibility of obtaining stable vertical oscillations of a biharmonic vibration platform with four unbalanced vibration exciters, not connected by kinematic transmissions, is demonstrated. For such a dynamic system, the validity of the well-known conditions for the existence and stability of synchronous motions of two vibration exciters rotating in opposite directions at identical frequencies is confirmed. It is shown that the biharmonic regime consists of two independent steady-state monoharmonic regimes, each with its own synchronous frequency, resulting in the excitation of biharmonic oscillations with variable motion asymmetry. The attainment of stable biharmonic oscillations is corroborated through numerical simulations and experimental validation.