Indirect inverse substructuring identification method for coupling dynamic stiffness of vibrational structures

Coupling dynamic stiffness is a key parameter in vibrational analysis of complex coupled structures, for both estimation of structural vibrational characteristics and design of vibration control. An indirect method of inverse substructuring analysis to identify the stiffness is studied further by using frequency response functions that are tested on the models of coupled structures. The theoretical effectiveness of this method is here verified by two ‘mass-rubber’ experimental models constructed as two-level substructures with mono-coupling and tri-coupling connections, and the identification error is also analyzed. The coincidence of numerical and experimental results show that the indirect method has better feasibility and effectiveness than the existing direct method of inverse substructuring analysis, and with more applicable conditions and higher acceptable precision in determining the stiffness. It provides more solid theoretical basis for the stiffness identification by inverse substructuring analysis.