Optimization method for the determination of Mooney-Rivlin material coefficients of the human breasts in-vivo using static and dynamic finite element models

A new method has been developed for sensitivity calculations of modal characteristics of bladed disks made of anisotropic materials. The method allows the determination of the sensitivity of the natural frequencies and mode shapes of mistuned bladed disks with respect to anisotropy angles that define the crystal orientation of the monocrystalline blades using full-scale finite element models. An enhanced method is proposed to provide high accuracy for the sensitivity analysis of mode shapes. An approach has also been developed for transforming the modal sensitivities to coordinate systems used in industry for description of the blade anisotropy orientations. The capabilities of the developed methods are demonstrated on examples of a single blade and a mistuned realistic bladed disk finite element models. The modal sensitivity of mistuned bladed disks to anisotropic material orientation is thoroughly studied.

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Robotic fixtureless assembly of sheet metal parts using dynamic finite element models: modelling and simulation

Proceedings of 1995 IEEE International Conference on Robotics and Automation ◽

10.1109/robot.1995.525639 ◽

2002 ◽

Cited By ~ 10

Author(s):

J.K. Mills ◽

J.G.-L. Ing

Keyword(s):

Finite Element ◽

Sheet Metal ◽

Modelling And Simulation ◽

Finite Element Models ◽

Metal Parts ◽

Sheet Metal Parts ◽

Dynamic Finite Element

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Modal Velocity-Based Multiaxial Fatigue Damage Evaluation Using Simplified Finite Element Models

Journal of Applied Mechanics ◽

10.1115/1.4047774 ◽

2020 ◽

Vol 87 (11) ◽

Cited By ~ 1

Author(s):

Kurthan Kersch ◽

Elmar Woschke

Keyword(s):

Finite Element ◽

Fatigue Damage ◽

Cross Section ◽

Multiaxial Fatigue ◽

Finite Element Models ◽

Damage Evaluation ◽

Geometric Factors ◽

The Relationship ◽

General Method

Abstract This work proposes a new method for the fatigue damage evaluation of vibrational loads, based on preceding investigations on the relationship between stresses and modal velocities. As a first step, the influence of the geometry on the particular relationship is studied. Therefore, an analytic expression for Euler Bernoulli beams with a non-constant cross section is derived. Afterward, a general method for obtaining geometric factors from finite element (FE) models is proposed. In order to ensure a fast fatigue damage evaluation, strongly simplified FE-models are used for the determination of both factors and measurement locations. The entire method is demonstrated on three mechanical structures and indicates a better compromise between effort and accuracy than existing methods. For all examples, the usage of velocities and geometric factors obtained from simplified FE models enables a sufficient fatigue damage calculation.

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Applying models of spatial interpolation for the approximation of responses in the refinement of parameters of finite element models

MATEC Web of Conferences ◽

10.1051/matecconf/201821201021 ◽

2018 ◽

Vol 212 ◽

pp. 01021

Author(s):

Anatoly Pikhalov ◽

Anton Zabelin

Keyword(s):

Finite Element ◽

Radial Basis Functions ◽

Element Model ◽

Optimization Method ◽

Latin Squares ◽

Basis Functions ◽

Finite Element Models ◽

Radial Basis ◽

High Level ◽

Parameter Values

The numerical experiment on refining the parameters of the finite element model of the beam by the method of approximating the responses is presented in the article. As mathematical models of joint-stock companies are used: linear combinations of radial-basis functions, and Kriging-models. These models are generated in the work on the basis of Latin squares and depend on the parameters to be refined (the moduli of elasticity of finite element groups of the beam). To obtain optimal values of the parameters, a genetic optimization method was used. The results of solving the optimization problem showed a high level of coincidence of the parameter values with a combination of response models obtained from dynamic and static types of calculations. It was also shown that when solving the problems of finite element models, it is sufficient to use models constructed only on the basis of radial-basis functions.

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