Vibration response analysis of plate with microfloating raft arrays under multi-point random excitation

Inspired by the traditional floating raft vibration suppression system, in order to solve the problem of random vibration of the plate, through miniaturizing the floating raft system and using the microfloating raft arrays to replace the distributed dynamic vibration absorbers, a plate with microfloating raft arrays is constructed in this paper. The vibration response equation of the structure under multi-point random excitation is established by using modal superposition method. The auto-power spectral density (APSD) of displacement is obtained by using MATLAB, and the influence of system parameters on the vibration response is analyzed. Optimal combination of parameters is obtained by the generalized pattern search algorithm. Vibration reduction effect of this structure is analyzed. The results show that redistribution of microfloating raft element interval and an increase in the thickness, flexural rigidity and damping of the plate could increase the vibration suppression effect. It is also shown that an increase in mass ratio and stiffness ratio of the microfloating raft element could significantly reduce the vibration of the plate. When it achieves the optimal vibration suppression effect, the mass ratio, the stiffness ratio and the damping ratio are 0.3, 8.8562 and 4.7660, respectively. Compared with other plate structures, the plate with microfloating raft arrays of optimal parameter has the minimum APSD of displacement and minimum energy.