A discrete-time, dynamic system method for the identification of the viscoelastic properties of a class of materials

Abstract

In this paper, a linear viscoelastic material is considered as a dynamic system. From this point of view, a dynamic system identification method is developed for the determination of the relaxation or creep function of the material from dynamic experimental measurements. First, the relation between the relaxation or creep function and the transfer function of the system is established by assuming a model of rational functions of polynomials for the transfer function. Second, a discrete-time system analysis method is introduced to identify the order and parameters of the proposed model from the discretetime series of both the input and output signals. The numerical examples given show that the proposed procedure is reasonable and the model is accurate and efficient.