Experimental Substructuring

On the physically consistent characterisation of a system for FRF-based substructuring

“…As a result, the subsystems are treated in terms of black boxes [28], with their input-output characteristics described without the need for a detailed description of its inner workings. Analogies with the presented method can be also found in the Operational Transfer Path Analysis (OTPA) concept, described for instance in Allen et al [29].…”

On the use of Lagrange Multiplier State-Space Substructuring in dynamic substructuring analysis

“…The selection of this subspace is difficult and strongly influences the obtained results [10]. If UCF is compared with the coupling form presented in [14] it has the advantage of just requiring the computation of one nullspace.…”

“…Firstly, the estimation of state-space models from the FRFs of components A and B is performed. Then, to validate UCF presented in section 6, the identified state-space models will be transformed into this coupling form and into the ones presented in [12] and [14]. The FRFs of the untransformed and of the three transformed identified models of each component are then compared (section 8.1).…”

“…This choice is hard to make and strongly affects the performance of the transformation [10]. Recently, a new coupling form that requires the computation of two nullspaces, but does not rely on the choice of any subspace was proposed in [14] and its performance will be also evaluated in this document.…”

Accuracy improvement method for dynamic substructuring models in vehicle systems

“…These measured data are unreliable because they depend on location. In particular, the DS model is vulnerable to FRF errors (Allen et al, 2020). Figure 11 shows a comparison of the estimated dynamic characteristics (i.e., FRFs) obtained using the FRFs measured from each substructure and the GCPs obtained from the assembled coupled test jig via equation (12) with and without VPT, along with the measured results of the actual coupled system.…”