The linear and nonlinear viscoelastic response of networks of cross-linked and bundled cytoskeletal filaments demonstrates remarkable scaling with both frequency and applied prestress, which helps elucidate the origins of the viscoelasticity. The frequency dependence of the shear modulus reflects the underlying single-filament relaxation dynamics for 0.1-10 rad/sec. Moreover, the nonlinear stra...

We present a physiologically based model that describes major properties of muscles and segmental dynamics during FES assisted standing-up. It accounts for relevant time-dependent and nonlinear properties (temporal and spatial summation, muscle fatigue, force-length and force-velocity relations, viscoelastic effects, nonlinear moment arms, choice of muscles stimulated, seat and upperbody intera...

The controllability of viscoelastic fields is a fundamental concept that defines some essential capabilities and limitations of the resulting materials. In this paper, we study the controllability of different homogeneous flow fields of viscoelastic fluids governed by the upper convected Maxwell model. The approach is largely based on the nonlinear geometric control theory. Through the analysis...

Plane Couette flow of viscoelastic fluids is shown to exhibit a purely elastic subcritical instability at a very small-Reynolds number in spite of being linearly stable. The mechanism of this instability is proposed and the nonlinear stability analysis of plane Couette flow of the Upper-Convected Maxwell fluid is presented. Above a critical Weissenberg number, a small finite-size perturbation i...

Series solution of nonlinear dynamic system containing fractional derivative is obtained by the homotopy analysis method (HAM). The solution via HAM has auxiliary parameter h̄ which can control the convergent of the series to obey the exact or numerical solution. The model of viscoelastic behavior of a one-degree-of-freedom oscillator consisting of a discrete mass and a viscoelastic spring is co...

This paper presents a simplified simulation technique for orthotropic viscoelastic films. Wrinkling is detected by a combined stress-strain criterion and an iterative scheme searches for the wrinkle angle using a pseudo-elastic material stiffness matrix based on a nonlinear viscoelastic constitutive model. This simplified model has been implemented in ABAQUS/Explicit and is able to compute the ...

We numerically model the brain dynamics during and after impulsive head translations using linear Partial Differential Equations (PDEs) describing viscoelastic solids and a nonlinear generalization of these PDEs describing incompressible, viscoelastic fluids. The brain matter motion and the sensitivity of the solutions with respect to the skull’s geometry differ substantially in the two cases. ...

There are many tactile devices for indentation examinations to measure mechanical properties of tissue. The purpose of this paper is to develop a portable indentation robotic device to show its usability for measuring the mechanical properties of a healthy abdominal tissue. These measurements will help to develop suitable mathematical models representing abdominal tissue. A 1-DOF portable robot...

A finite strain nonlinear viscoelastic constitutive model is used to study the uniaxial tension behaviour of a chemical polyampholyte (PA) gel.

Temperature has an influence on damping characteristics of the viscoelastic damping structure. The change of the damping characteristics of the structure under the cycle load is a dynamic and coupled process. The hyperelastic-viscoelastic model was used to describe nonlinear deformation and viscoelasticity simultaneously. The temperature distribution and change of the damping characteristics un...