Dynamic stiffness of resilient materials based on accurate measurement of dynamic force and dynamic displacement

Dynamic stiffness is a useful parameter to characterize elastic and viscous properties of several typologies of resilient materials, used in many engineering applications to decouple structural elements or mechanical components. The dynamic response of a resilient material, depending on its ability to store or dissipate energy, affects the behavior of the mechanical system, in which it is applied. In this paper a new set-up for accurate measurements of dynamic stiffness of resilient materials is presented. The measurement system allows to quantify both dynamic force and real dynamic displacement of the mass-spring (loading mass-resilient material) system, by means of laser Doppler velocimetry. Moreover the proposed method can be easily "tuned" in order to evaluate the elastic and viscoelastic response of resilient materials depending on specific technical/practical applications, e.g., as a function of different loading masses, input forces, frequencies of excitation and true dynamic displacement.