Inverse Finite Element Characterization of Soft Tissues Using Impact Experiments and Taguchi Methods

The objective of this study is to establish a methodology to identify the dynamic properties of soft tissues. Nineteen in vitro impact tests are performed on human muscles at three average strain rates ranging from 136/s to 262/s. Muscle tissues are compressed uniaxially up to 50% strain level. Subsequently, finite element simulations replicating the experimental conditions are executed using the PAM-CRASH, explicit finite element solver. The material properties of the muscles, modelled as linear isotropic viscoelastic material, are identified using inverse finite element mapping of test data using Taguchi methods. Engineering stress engineering strain curves from experimental data and finite element models are computed and compared during identification of material properties at the above mentioned strain rates. Response of finite element models, with extracted material properties, falls within experimental corridors indicating the validation of the methodology adopted.