Backscattering from a baffled finite plate strip with fuzzy attachments

A formulation for predicting the effect of fuzzy attachments on the response of a master structure was originally provided by the fuzzy structure theory of Soize. An extension of Soize's theory was recently developed by Pierce et al. (ASME 1993 Winter Meeting, New Orleans, LA). This new formulation is applied to a finite plate strip simply supported in an infinite rigid baffle. An incident plane-wave pulse is incident upon the plate and the effect of the fuzzy attachments on the target strength is determined. The primary effect of a large number of 1-DOF fuzzy attachments is an apparent added mass and an apparent added damping to the plate. Both of these effects depend directly on the mass distribution of the 1-DOF attachments with respect to their natural frequencies. A representative distribution is considered. It is found that if the most probable natural frequency of the fuzzy attachments coincides with a plate resonance, the amplitude at the target frequency is significantly reduced, the amount of reduction increasing as the total mass of all attachments increases. Plate resonances above the target frequency are shifted upward, and those below are shifted downward.