Parameter Estimation of Rheological Object Based on FE Simulation and Nonlinear Optimization

There are many kinds of deformable objects in our living life. Some of them demonstrate rheological behaviors, such as human tissues, food, and clay. Comparing with elastic or viscoelastic objects, rheological objects have not been studied intensively. Especially, effective methods for parameter identification have not been established until now. In this paper, we summarize two FE dynamic models associated with three-element and fourelement physical model respectively. According to the analysis of simulation results, we proposed an approach for estimating physical parameters of rheological objects based on FE simulation and nonlinear optimization. This method aims at minimizing the difference of deformed shape and force response between experiment and simulation. This method take both deformed shape and force response into consideration. Experiment is conducted by using commercial clay. The identification results show that the four-element physical model is more appropriate to describe rheological behaviors than three-element model.