Structural vibration is a natural phenomenon exhibited by all structures, by virtue of simply possessing mass and having an associated structural stiffness. Thus, any structure or assembly of structures, with a mass attribution, will possess some structural stiffness. This stiffness will characterize the vibrational response of the structure, depending on the type of boundary conditions constraining the structure. For complex structural configurations, this vibrational response can be determined by numerical techniques, such as the finite element method, which allows calculation of the natural frequencies of vibration of the structure and the respective mode shapes of vibration associated with each of these natural frequencies.