Some differences were found between the numerical and experimental data. However they follow the same
trends. LQR2COO is the best performer and ICOO is the following one. ICOO is an interesting solution if a
collocated control is employed. For this strategy in particular, a comparison between the experimental and numerical
FRFs are presented in Fig. 4, showing a good agreement in general terms. Although, slightly differences on the
magnitude of the first mode of vibration in terms of relative displacements can be observed. Anyway, the modal
quantities, frequencies and damping ratios are very close to each other