We present a time-dependent finite element model of the human knee joint of full 3D geometric complexity together with advanced numerical algorithms needed for its simulation. The model comprises bones, cartilage and the major ligaments, while patella and menisci are still missing. Bones are modeled by linear elastic materials, cartilage by linear viscoelastic materials, and ligaments by onedim...

As a matter of fact, the solution space of many systems of ordinary differential (OD) or partial differential (PD) equations in engineering or mathematical physics ”can/cannot” be parametrized by a certain number of arbitrary functions behaving like ”potentials”. In view of the explicit examples to be met later on, it must be noticed that the parametrizing operator, though often of the first or...

Within a theory of liquid-crystals-like materials based on a generalized Cosserat-type formulation, it is shown that continuous distributions of inhomogeneities may exist at the microstructural level.

A rigid-plastic Cosserat model has been used to study dense, fully developed flow of granular materials through a vertical channel. Frictional models based on the classical continuum do not predict the occurrence of shear layers, at variance with experimental observations. This feature has been attributed to the absence of a material length scale in their constitutive equations. The present mod...

Using $$\Gamma $$ -convergence arguments, we construct a nonlinear membrane-like Cosserat shell model on curvy reference configuration starting from geometrically nonlinear, physically linear three-dimensional isotropic model. Even if the theory is of order O(h) in thickness h, by comparison to membrane models proposed classical elasticity, beside change metric, still capable capturing transver...

In spite of recent progress, soft robotics still suffers from a lack of unified modeling framework. Nowadays, the most adopted model for the design and control of soft robots is the piece-wise constant curvature model, with its consolidated benefits and drawbacks. In this work, an alternative model for multisection soft robots dynamics is presented based on a discrete Cosserat approach, which, ...

This paper proposes a method for performing predictive simulation of cardiac surgery. It applies a hybrid approach to model the deformation of blood vessels. The hybrid blood vessel model consists of a reference Cosserat rod and a surface mesh. The reference Cosserat rod models the blood vessel's global bending, stretching, twisting and shearing in a physically correct manner, and the surface m...