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As the demand for the transmission of electric power and communication signals in automotive and aerospace vehicles increases, so does the number of structures comprising simplified one-dimensional attachments, such as electrical cabling, affixed to a host plate like primary structure. These attachments are typically uncertain in their geometric or material properties, potentially affecting the response of the built-up structure. Difficulties then arise in the prediction of the response of the assembly. This study shows how the variability, due to the uncertain attachments, might be reduced by considering flexible connections. A mobility analysis compares systems connected with either rigid links or elastic springs. A frequency is identified at which the assembly dynamically uncouples; the effect on the host response variability due to the uncertain attachment decreases above this frequency with a reduction of the order of 60 dB in the coefficient of variation. This uncoupling or effective isolation frequency can be simply estimated from the mobility of the elastic connection and the properties of the nominal structural attachment. For design purposes, this frequency can be adjusted to achieve a more predictable response above a given frequency.

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This paper investigates the vibrational behaviour and attenuation performance of a plate connected to a plate-like resonator equipped with a 1D acoustic black hole. The ABH principle relies on trapping the incident waves and consequently absorbing the incoming mechanical energy. Conversely, the ABH acts as a conventional dynamic absorber in which the vibration modes of the wedge act as a multifrequency resonator when attached to a host structure. The typically added damping layer enriches its dynamic, providing superior attenuation across a broader frequency band. This plate-like resonator can be used as a vibration control alternative to the use of single or multiple resonators attached to the host structure. In this work, a mobility-based approach is used to connect both the host plate and the plate-like resonator with an ABH termination. The response of both structures is given by a Finite Element model implemented by the authors in MATLAB, and the point connections are assumed to be rigid. The results are compared to that of a uniform plate acting as a multifrequency resonator, and it is shown that the ABH-based vibration attenuation leads to a reduction of up to 20 dB across multiple third-octave bands in the mobility response of the coupled system. Additionally, the energy flow is also investigated, and it is shown that the ABH-plate resonator yields up to 50 dB reduction also over multiple third-octave bands in the spatially averaged kinetic energy spectra. The addition of the film of viscoelastic material enhances its attenuation performance by up to 30 dB compared to the geometric effect due to the ABHs. The results suggest that this ABH-based solution can be a viable engineering approach and opens the way for new and innovative solutions in vibration control.