REVIEW OF METHODS IN NONLINEAR MODELS' PARAMETERS IDENTIFICATION

A variety of engineering tasks nowadays leads to an inverse analysis problem. In common engineering applications, a goal is to determine the initial conditions and properties from physical experiments or, equivalently, to find a set of parameters for a numerical model describing the experiment. Therefore, existence of such numerical model is assumed in this work and the task is to find parameters of this model to match outputs from model with results from the experiment. In overall, there are two main philosophies to solution of this problem. A forward (classical) mode/direction is based on the definition of an error function of the difference between outputs of the model and experimental measurements. A solution comes with the minimum of this function. The second philosophy, an inverse mode, assumes existence of an inverse relationship between outputs and inputs. Both philosophies are introduced in the contribution and thoroughly discussed. As examples, the parameters identification of several nonlinear material models that has been encountered by authors during the last seven years is presented.