Inverse substructure method of three-substructures coupled system and its application in product-transport-system

Abstract

An inverse substructure method is developed for the analysis of the dynamical characteristics of a three-substructures coupled system based on the inverse substructure method of a two-substructures coupled system. The unknown substructure-level frequency response functions (FRFs) and coupling stiffness can be predicted, and the system-level response of key components can be obtained by using the method when the system-level FRFs needed are all measured. To verify the validity of the inverse substructure method of a three-substructures coupled system, a lumped mass-spring-damper model with three substructures coupled is taken as an example for numerical validation. The prediction is exactly the same as the ‘‘Given’’. To further check out the accuracy of the method, the experiment of a physical prototype is carried out, and the predicted substructure-level FRFs are in good agreement with those that are measured. The method is applied to the analysis of a product-transport-system, which is treated as a coupled system composed of a key component, a product and a vehicle. The effect of the coupling stiffness on the dynamic response of key components is investigated. The result indicates that reducing the coupling stiffness of the product-vehicle interface can largely lower the response of key components.