We study the stability of magnetorheological elastomers (MREs) undergoing finite deformations in the presence of a magnetic field and derive a general condition for the onset of macroscopic instabilities. In particular, we focus on anisotropic MREs with magnetoactive particles that are aligned along a particular direction, forming chain-like structures. We idealize the microstructure of such an...

We present a variational model to study the quasistatic growth of brittle cracks in hyperelastic materials, in the framework of finite elasticity, taking into account the non-interpenetration condition.

The aim of this paper is to establish a nonlinear variational approach to the reconstruction of moving density images from indirect dynamic measurements. Our approach is to model the dynamics as a hyperelastic deformation of an initial density including preservation of mass. Consequently we derive a variational regularization model for the reconstruction, which besides the usual data fidelity a...

In this work, we derive a closed-form criterion for the onset of cavitation in compressible, isotropic, hyperelastic solids subjected to non-symmetric loading conditions. The criterion is based on the solution of a boundary value problem where a hyperelastic solid, which is infinite in extent and contains a single vacuous inhomogeneity, is subjected to uniform displacement boundary conditions. ...

In this paper we introduce a elastic and hyperelastic model to describe the pressure dependent material stress in joint cartilage. We used the pressure dependent E-modulus E = f(s) to calculate the material stress. E = f(s) is a degree 4 polynomial [1]. The indentor was pressed 0.4 mm into the tissue. The results show that the maximal stress at the contact zone between indentor and cartilage ac...

Static deflection as well as free and forced nonlinear vibration of thin square plates made of hyperelastic materials are investigated. Two types of materials, namely rubber and soft biological tissues, are considered. The involved physical nonlinearities are described through the Neo-Hookean, Mooney-Rivlin, and Ogden hyperelastic laws; geometrical nonlinearities are modeled by the Novozhilov n...

Hill's one-dimensional three-element model has often been used for formulating a three-dimensional skeletal muscle constitutive model, which generally involves several material parameters. However, only few of these parameters have physical meanings and can be experimentally determined. In this paper, a parametric study of a Hill-type hyperelastic skeletal muscle model is performed. First, the ...

The aim of the present work was to investigate the stress relaxation phenomena of the heel pad region under different loading conditions. A 31-year-old healthy female was enrolled in this study and her left foot underwent both MRI and experimental compression tests. Experimental results were compared with those obtained from finite element analysis performed on numerical 3D subject-specific hee...

The biomechanical properties of soft tissue derived from experimental measurements are critical for developing a reality-based model for minimally invasive surgical training and simulation. In our research, we focus on developing a biomechanical model of the liver under large tissue deformation. This paper presents the experimental apparatus, experimental data, and formulations to model the exp...

We discuss and solve an inverse problem in nonlinear elasticity imaging in which we recover spatial distributions of hyperelastic material properties from measured displacement fields. This problem has applications to elasticity imaging of soft tissue because the strain dependence of the apparent stiffness may potentially be used to differentiate between malignant and normal tissues. We account...