Biomechanical characterization with inverse FE model parameter estimation: Macro and micro applications

An inverse finite element (FE) model parameter estimation algorithm can be used to characterize a realistic biomechanical properties, which consider (or include) the material nonlinearity, contact mechanics, complex boundary conditions, and geometrical constraints in the modeling. In this study, biomechanical experiments on macro and micro samples are conducted. Macro indentation experiments on porcine livers were performed to measure the force behavior using one-dimensional indentation device. The force response of the human liver cancer cells was also measured by the atomic force microscope (AFM). The mechanical behavior of porcine livers (macro) and human liver cancer cells (micro) were characterized with inverse FE model parameter estimation algorithm via hyperelastic and linear viscoelastic models. The developed models are suitable for computing accurate reaction force on tools and deformation of biomechanical tissues.