The Experts below are selected from a list of 26715 Experts worldwide ranked by ideXlab platform
Pierre-françois Leyvraz - One of the best experts on this subject based on the ideXlab platform.
-
technical noteviscoelastic Constitutive Law in large deformations application to human knee ligaments and tendons
Journal of Biomechanics, 1998Co-Authors: Dominique P. Pioletti, J. F. Benvenuti, L. R. Rakotomanana, Pierre-françois LeyvrazAbstract:Traction tests on soft tissues show that the shape of the stress–strain curves depends on the strain rate at which the tests are performed. Many of the Constitutive models that have been proposed fail to properly consider the effect of the strain rate when large deformations are encountered. In the present study, a framework based on elastic and viscous potentials is developed. The resulting Constitutive Law is valid for large deformations and satisfies the principles of thermodynamics. Three parameters — two for the elasticity and one for the viscosity — were enough to precisely fit the non-linear stress–strain curves obtained at different strain rates with human cruciate ligaments and patellar tendons. The identification results then in a realistic, three-dimensional viscoelastic Constitutive Law. The developed Constitutive Law can be used regardless of the strain or rotation values. It can be incorporated into a finite element program to model the viscoelastic behavior of ligaments and tendons under dynamic situations.
-
viscoelastic Constitutive Law in large deformations application to human knee ligaments and tendons
Journal of Biomechanics, 1998Co-Authors: Dominique P. Pioletti, J. F. Benvenuti, L. R. Rakotomanana, Pierre-françois LeyvrazAbstract:Traction tests on soft tissues show that the shape of the stress—strain curves depends on the strain rate at which the tests are performed. Many of the Constitutive models that have been proposed fail to properly consider the e⁄ect of the strain rate when large deformations are encountered. In the present study, a framework based on elastic and viscous potentials is developed. The resulting Constitutive Law is valid for large deformations and satisfies the principles of thermodynamics. Three parameters — two for the elasticity and one for the viscosity — were enough to precisely fit the non-linear stress—strain curves obtained at di⁄erent strain rates with human cruciate ligaments and patellar tendons. The identification results then in a realistic, three-dimensional viscoelastic Constitutive Law. The developed Constitutive Law can be used regardless of the strain or rotation values. It can be incorporated into a finite element program to model the viscoelastic behavior of ligaments and tendons under dynamic situations. ( 1998 Elsevier Science Ltd. All rights reserved.
-
Viscoelastic Constitutive Law in large deformations: Application to human knee ligaments and tendons
Journal of Biomechanics, 1998Co-Authors: Dominique P. Pioletti, J. F. Benvenuti, L. R. Rakotomanana, Pierre-françois LeyvrazAbstract:Traction tests on soft tissues show that the shape of the stress-strain curves depends on the strain rate at which the tests are performed. Many of the Constitutive models that have been proposed fail to properly consider the effect of the strain rate when large deformations are encountered. In the present study, a framework based on elastic and viscous potentials is developed. The resulting Constitutive Law is valid for large deformations and satisfies the principles of thermodynamics. Three parameters - two for the elasticity and one for the viscosity - were enough to precisely fit the non-linear stress-strain curves obtained at different strain rates with human cruciate ligaments and patellar tendons. The identification results then in a realistic, three-dimensional viscoelastic Constitutive Law. The developed Constitutive Law can be used regardless of the strain or rotation values. It can be incorporated into a finite element program to model the viscoelastic behavior of ligaments and tendons under dynamic situations.
Dominique P. Pioletti - One of the best experts on this subject based on the ideXlab platform.
-
technical noteviscoelastic Constitutive Law in large deformations application to human knee ligaments and tendons
Journal of Biomechanics, 1998Co-Authors: Dominique P. Pioletti, J. F. Benvenuti, L. R. Rakotomanana, Pierre-françois LeyvrazAbstract:Traction tests on soft tissues show that the shape of the stress–strain curves depends on the strain rate at which the tests are performed. Many of the Constitutive models that have been proposed fail to properly consider the effect of the strain rate when large deformations are encountered. In the present study, a framework based on elastic and viscous potentials is developed. The resulting Constitutive Law is valid for large deformations and satisfies the principles of thermodynamics. Three parameters — two for the elasticity and one for the viscosity — were enough to precisely fit the non-linear stress–strain curves obtained at different strain rates with human cruciate ligaments and patellar tendons. The identification results then in a realistic, three-dimensional viscoelastic Constitutive Law. The developed Constitutive Law can be used regardless of the strain or rotation values. It can be incorporated into a finite element program to model the viscoelastic behavior of ligaments and tendons under dynamic situations.
-
viscoelastic Constitutive Law in large deformations application to human knee ligaments and tendons
Journal of Biomechanics, 1998Co-Authors: Dominique P. Pioletti, J. F. Benvenuti, L. R. Rakotomanana, Pierre-françois LeyvrazAbstract:Traction tests on soft tissues show that the shape of the stress—strain curves depends on the strain rate at which the tests are performed. Many of the Constitutive models that have been proposed fail to properly consider the e⁄ect of the strain rate when large deformations are encountered. In the present study, a framework based on elastic and viscous potentials is developed. The resulting Constitutive Law is valid for large deformations and satisfies the principles of thermodynamics. Three parameters — two for the elasticity and one for the viscosity — were enough to precisely fit the non-linear stress—strain curves obtained at di⁄erent strain rates with human cruciate ligaments and patellar tendons. The identification results then in a realistic, three-dimensional viscoelastic Constitutive Law. The developed Constitutive Law can be used regardless of the strain or rotation values. It can be incorporated into a finite element program to model the viscoelastic behavior of ligaments and tendons under dynamic situations. ( 1998 Elsevier Science Ltd. All rights reserved.
-
Viscoelastic Constitutive Law in large deformations: Application to human knee ligaments and tendons
Journal of Biomechanics, 1998Co-Authors: Dominique P. Pioletti, J. F. Benvenuti, L. R. Rakotomanana, Pierre-françois LeyvrazAbstract:Traction tests on soft tissues show that the shape of the stress-strain curves depends on the strain rate at which the tests are performed. Many of the Constitutive models that have been proposed fail to properly consider the effect of the strain rate when large deformations are encountered. In the present study, a framework based on elastic and viscous potentials is developed. The resulting Constitutive Law is valid for large deformations and satisfies the principles of thermodynamics. Three parameters - two for the elasticity and one for the viscosity - were enough to precisely fit the non-linear stress-strain curves obtained at different strain rates with human cruciate ligaments and patellar tendons. The identification results then in a realistic, three-dimensional viscoelastic Constitutive Law. The developed Constitutive Law can be used regardless of the strain or rotation values. It can be incorporated into a finite element program to model the viscoelastic behavior of ligaments and tendons under dynamic situations.
Sachin Goyal - One of the best experts on this subject based on the ideXlab platform.
-
Estimating Constitutive Law of a Filament From its Deformed Shapes Using Input Reconstruction
Volume 8: 27th Conference on Mechanical Vibration and Noise, 2015Co-Authors: Roshan A. Chavan, Harish J. Palanthandalam-madapusi, Sachin GoyalAbstract:Twisting and bending dynamics of biological filaments such as DNA play a central role in their biological activity including gene expression. The elastic rod model is an efficient tool to simulate such deformations. However, the accuracy of elastic rod predictions depend strongly on the Constitutive Law, which follows from the atomistic structure of the DNA molecule and is known to be nonlinear and to vary along the length according to the base pair sequence of the DNA. Unfortunately, it is impractical to derive the Constitutive Law analytically from the atomistic structure. Identification of the nonlinear sequence-dependent Constitutive Law from experimental data and feasible molecular dynamics simulations remains a significant challenge. In this paper, we extend earlier work by employing techniques based on input reconstruction and state estimation filters to estimate the Constitutive Law using molecular dynamics data of deformations in bio-filaments.Copyright © 2015 by ASME
-
A Method for Identification of the Constitutive Law of Biological Filaments From Their Dynamic Equilibria
Volume 6: 11th International Conference on Multibody Systems Nonlinear Dynamics and Control, 2015Co-Authors: Soheil Fatehiboroujeni, Sachin Goyal, Apostol GramadaAbstract:There are several biological filaments that play vital role in cellular processes via twisting and bending deformations. From the double-stranded DNA molecule containing genetic information to the cytoskeletal fibers that provide shape to the cell, biological filaments undergo conformational changes as they perform their biological tasks. Therefore the ability of a filament to deform, which depends on their atomistic structure, is a characteristic property that governs its biological functions. Since there is no direct analytic method to derive the deformability or Constitutive Law of such filaments from their atomistic structure, the Constitutive Law has to be identified from their actual deformations. An inverse approach based on a continuum rod model was developed recently that uses deformations in static equilibrium to estimate the Constitutive Law in bending and torsion. We extend the inverse method to use dynamic states of deformations, and consequently expand its scope to leverage a wide variety of choices in molecular dynamics simulations for identifying the Constitutive Law. This paper presents and validates the technique applying it to filaments with artificial atomistic structure.Copyright © 2015 by ASME
-
Constitutive-Law Estimation of Bio-Filaments from their MD Simulations
Biophysical Journal, 2013Co-Authors: Swati Verma, Harish J. Palanthandalam-madapusi, Sachin GoyalAbstract:Continuum-mechanics based models have recently evolved as viable tools to efficiently simulate large deformations of bio-filaments. However, the deformations predicted from these models are highly sensitive to their underlying Constitutive-Law model. Unfortunately, lack of rigorous methods for identification of Constitutive-Law models leaves no option but to make ad hoc assumptions and crude approximations in Constitutive-Law models. We recently developed a novel system identification technique together with an inverse rod model that can systematically estimate the Constitutive Laws of bio-filaments from their discrete structure (MD) simulations; refer to [J. Appl. Mech., 79(5), p. 051005] and [Automatica 47(6), p. 1175-1182]. An attempt to apply this technique to microtubules suggests that traditionally assumed linearly elastic Constitutive Laws are inaccurate, and backs the claim of existence of twist-tension coupling in the microtubules. Furthermore, microtubules exhibit kinking with hysteresis supporting the hypothesis of a non-convex Constitutive Law.
-
Constitutive Law modeling of microfilaments from their discrete structure simulations a method based on an inverse approach applied to a static rod model
Journal of Applied Mechanics, 2012Co-Authors: Adam R. Hinkle, Sachin Goyal, Harish J PalanthandalammadapusiAbstract:Twisting and bending deformations are crucial to the biological functions of several microfilaments such as DNA molecules. Although continuum-rod models have emerged as efficient tools to describe the nonlinear dynamics of these deformations, a major roadblock in the continuum–mechanics-based description of microfilaments is the accurate modeling of the Constitutive Law, which follows from their atomistic-level structure and interactions. In this paper, we present a method for estimating the Constitutive Law using a static rod model and deformed configuration data generated from discrete-structure simulations. Furthermore, we illustrate the method on a filament with an artificial discrete-structure. We simulate its deformation in response to a prescribed loading using a multibody dynamics (MBD) solver. Using position data generated from the MBD solver, we first estimate the curvature of the filament, and subsequently use it to estimate the effective relationship between the restoring moment and curvature.
-
robust estimation of nonlinear Constitutive Law from static equilibrium data for modeling the mechanics of dna
Automatica, 2011Co-Authors: Harish J Palanthandalammadapusi, Sachin GoyalAbstract:Long length-scale structural deformations of DNA play a central role in many biological processes including gene expression. The elastic rod model, which uses a continuum approximation, has emerged as a viable tool to model deformations of several biofilaments including DNA molecules. The elastic rod model predictions are however very sensitive to the model of Constitutive Law (material properties) of the molecule. Robust estimation of the Constitutive Law from experimental data and feasible molecular dynamics simulations remains a significant challenge. In this paper, we develop a two-step technique to use elastic rod model equations in combination with limited data to estimate the nonlinear Constitutive Law governing DNA molecules. We first cast the elastic rod model equations in state-space form and express the effect of the unknown Constitutive Law as an unknown input to the system. We then describe the two-step technique to estimate the unknown Constitutive Law. Finally, we investigate the robustness of this technique through simulations and discuss various generalizations.
J. F. Benvenuti - One of the best experts on this subject based on the ideXlab platform.
-
technical noteviscoelastic Constitutive Law in large deformations application to human knee ligaments and tendons
Journal of Biomechanics, 1998Co-Authors: Dominique P. Pioletti, J. F. Benvenuti, L. R. Rakotomanana, Pierre-françois LeyvrazAbstract:Traction tests on soft tissues show that the shape of the stress–strain curves depends on the strain rate at which the tests are performed. Many of the Constitutive models that have been proposed fail to properly consider the effect of the strain rate when large deformations are encountered. In the present study, a framework based on elastic and viscous potentials is developed. The resulting Constitutive Law is valid for large deformations and satisfies the principles of thermodynamics. Three parameters — two for the elasticity and one for the viscosity — were enough to precisely fit the non-linear stress–strain curves obtained at different strain rates with human cruciate ligaments and patellar tendons. The identification results then in a realistic, three-dimensional viscoelastic Constitutive Law. The developed Constitutive Law can be used regardless of the strain or rotation values. It can be incorporated into a finite element program to model the viscoelastic behavior of ligaments and tendons under dynamic situations.
-
viscoelastic Constitutive Law in large deformations application to human knee ligaments and tendons
Journal of Biomechanics, 1998Co-Authors: Dominique P. Pioletti, J. F. Benvenuti, L. R. Rakotomanana, Pierre-françois LeyvrazAbstract:Traction tests on soft tissues show that the shape of the stress—strain curves depends on the strain rate at which the tests are performed. Many of the Constitutive models that have been proposed fail to properly consider the e⁄ect of the strain rate when large deformations are encountered. In the present study, a framework based on elastic and viscous potentials is developed. The resulting Constitutive Law is valid for large deformations and satisfies the principles of thermodynamics. Three parameters — two for the elasticity and one for the viscosity — were enough to precisely fit the non-linear stress—strain curves obtained at di⁄erent strain rates with human cruciate ligaments and patellar tendons. The identification results then in a realistic, three-dimensional viscoelastic Constitutive Law. The developed Constitutive Law can be used regardless of the strain or rotation values. It can be incorporated into a finite element program to model the viscoelastic behavior of ligaments and tendons under dynamic situations. ( 1998 Elsevier Science Ltd. All rights reserved.
-
Viscoelastic Constitutive Law in large deformations: Application to human knee ligaments and tendons
Journal of Biomechanics, 1998Co-Authors: Dominique P. Pioletti, J. F. Benvenuti, L. R. Rakotomanana, Pierre-françois LeyvrazAbstract:Traction tests on soft tissues show that the shape of the stress-strain curves depends on the strain rate at which the tests are performed. Many of the Constitutive models that have been proposed fail to properly consider the effect of the strain rate when large deformations are encountered. In the present study, a framework based on elastic and viscous potentials is developed. The resulting Constitutive Law is valid for large deformations and satisfies the principles of thermodynamics. Three parameters - two for the elasticity and one for the viscosity - were enough to precisely fit the non-linear stress-strain curves obtained at different strain rates with human cruciate ligaments and patellar tendons. The identification results then in a realistic, three-dimensional viscoelastic Constitutive Law. The developed Constitutive Law can be used regardless of the strain or rotation values. It can be incorporated into a finite element program to model the viscoelastic behavior of ligaments and tendons under dynamic situations.
L. R. Rakotomanana - One of the best experts on this subject based on the ideXlab platform.
-
technical noteviscoelastic Constitutive Law in large deformations application to human knee ligaments and tendons
Journal of Biomechanics, 1998Co-Authors: Dominique P. Pioletti, J. F. Benvenuti, L. R. Rakotomanana, Pierre-françois LeyvrazAbstract:Traction tests on soft tissues show that the shape of the stress–strain curves depends on the strain rate at which the tests are performed. Many of the Constitutive models that have been proposed fail to properly consider the effect of the strain rate when large deformations are encountered. In the present study, a framework based on elastic and viscous potentials is developed. The resulting Constitutive Law is valid for large deformations and satisfies the principles of thermodynamics. Three parameters — two for the elasticity and one for the viscosity — were enough to precisely fit the non-linear stress–strain curves obtained at different strain rates with human cruciate ligaments and patellar tendons. The identification results then in a realistic, three-dimensional viscoelastic Constitutive Law. The developed Constitutive Law can be used regardless of the strain or rotation values. It can be incorporated into a finite element program to model the viscoelastic behavior of ligaments and tendons under dynamic situations.
-
viscoelastic Constitutive Law in large deformations application to human knee ligaments and tendons
Journal of Biomechanics, 1998Co-Authors: Dominique P. Pioletti, J. F. Benvenuti, L. R. Rakotomanana, Pierre-françois LeyvrazAbstract:Traction tests on soft tissues show that the shape of the stress—strain curves depends on the strain rate at which the tests are performed. Many of the Constitutive models that have been proposed fail to properly consider the e⁄ect of the strain rate when large deformations are encountered. In the present study, a framework based on elastic and viscous potentials is developed. The resulting Constitutive Law is valid for large deformations and satisfies the principles of thermodynamics. Three parameters — two for the elasticity and one for the viscosity — were enough to precisely fit the non-linear stress—strain curves obtained at di⁄erent strain rates with human cruciate ligaments and patellar tendons. The identification results then in a realistic, three-dimensional viscoelastic Constitutive Law. The developed Constitutive Law can be used regardless of the strain or rotation values. It can be incorporated into a finite element program to model the viscoelastic behavior of ligaments and tendons under dynamic situations. ( 1998 Elsevier Science Ltd. All rights reserved.
-
Viscoelastic Constitutive Law in large deformations: Application to human knee ligaments and tendons
Journal of Biomechanics, 1998Co-Authors: Dominique P. Pioletti, J. F. Benvenuti, L. R. Rakotomanana, Pierre-françois LeyvrazAbstract:Traction tests on soft tissues show that the shape of the stress-strain curves depends on the strain rate at which the tests are performed. Many of the Constitutive models that have been proposed fail to properly consider the effect of the strain rate when large deformations are encountered. In the present study, a framework based on elastic and viscous potentials is developed. The resulting Constitutive Law is valid for large deformations and satisfies the principles of thermodynamics. Three parameters - two for the elasticity and one for the viscosity - were enough to precisely fit the non-linear stress-strain curves obtained at different strain rates with human cruciate ligaments and patellar tendons. The identification results then in a realistic, three-dimensional viscoelastic Constitutive Law. The developed Constitutive Law can be used regardless of the strain or rotation values. It can be incorporated into a finite element program to model the viscoelastic behavior of ligaments and tendons under dynamic situations.