Design of Lightweight Composite Structures: A Parameter Free Structural Optimization Approach

This contribution presents computational concepts and algorithmic techniques for simulation and gradient-based optimization of geometrically nonlinear and large-scale finite element models of composite structures. Several industrial application examples illustrate the methods, show the applicability to large problems, and prove the high parallel efficiency.

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Affordable structural optimization for large-size dynamic finite element models

10.2514/6.1997-1112 ◽

1997 ◽

Author(s):

Francois Hemez ◽

Emmanuel Pagnacco ◽

Francois Hemez ◽

Emmanuel Pagnacco

Keyword(s):

Finite Element ◽

Structural Optimization ◽

Finite Element Models ◽

Dynamic Finite Element ◽

Large Size

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Topology Synthesis of Compliant Mechanisms for Nonlinear Force-Deflection and Curved Path Specifications

Journal of Mechanical Design ◽

10.1115/1.1333096 ◽

1999 ◽

Vol 123 (1) ◽

pp. 33-42 ◽

Cited By ~ 98

Author(s):

A. Saxena ◽

G. K. Ananthasuresh

Keyword(s):

Finite Element ◽

Linear Models ◽

Compliant Mechanisms ◽

Synthesis Method ◽

Design Sensitivity ◽

Finite Element Models ◽

Geometrically Nonlinear ◽

Linear Elastic ◽

Nonlinear Design ◽

Nonlinear Force

Optimal design methods that use continuum mechanics models are capable of generating suitable topology, shape, and dimensions of compliant mechanisms for desired specifications. Synthesis procedures that use linear elastic finite element models are not quantitatively accurate for large displacement situations. Also, design specifications involving nonlinear force-deflection characteristics and generation of a curved path for the output port cannot be realized with linear models. In this paper, the synthesis of compliant mechanisms is performed using geometrically nonlinear finite element models that appropriately account for large displacements. Frame elements are chosen because of ease of implementation of the general approach and their ability to capture bending deformations. A method for nonlinear design sensitivity analysis is described. Examples are included to illustrate the usefulness of the synthesis method.

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Single-trabecula building block for large-scale finite element models of cancellous bone

Medical & Biological Engineering & Computing ◽

10.1007/bf02350998 ◽

2004 ◽

Vol 42 (4) ◽

pp. 549-556 ◽

Cited By ~ 31

Author(s):

D. Dagan ◽

M. Be'ery ◽

A. Gefen

Keyword(s):

Finite Element ◽

Cancellous Bone ◽

Building Block ◽

Large Scale ◽

Finite Element Models

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Micro-CT-Based Large Scale Linear Finite Element Models Predict the Strength of Human Thoracic and Lumbar Vertebral Bodies

ASME 2007 Summer Bioengineering Conference ◽

10.1115/sbc2007-176699 ◽

2007 ◽

Author(s):

Yener N. Yeni ◽

Do-Gyoon Kim ◽

Roger R. Zauel ◽

Evan M. Johnson ◽

Dianna D. Cody

Keyword(s):

Finite Element ◽

Large Scale ◽

Quantitative Computed Tomography ◽

Finite Element Models ◽

Micro Ct ◽

Linear Finite Element ◽

Vertebral Strength ◽

Local Properties ◽

Vertebral Bodies ◽

Architectural Detail

Vertebral fractures are among the most common and debilitating fractures. Structural organization of cancellous and cortical bone in a vertebra and their local properties are important factors that determine the strength of a vertebra. Linear finite element models utilizing Quantitative Computed Tomography (QCT) images have proven useful for predicting vertebral strength and are potentially useful in predicting risk of fracture in a clinical setting [1]. However, the amount of architectural detail in these models is not sufficient for studying trabecular stress and strains, and their relationship with the microscopic structure, which is important for understanding the mechanisms behind vertebral fragility.

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Real Time Techniques for Nonlinear Tissue Deformation in Surgical Simulation

ASME 2007 Summer Bioengineering Conference ◽

10.1115/sbc2007-172518 ◽

2007 ◽

Author(s):

Suvranu De ◽

Yi-Je Lim

Keyword(s):

Finite Element ◽

Real Time ◽

Surgical Simulation ◽

Computational Technique ◽

Finite Element Models ◽

Geometrically Nonlinear ◽

Time Performance ◽

Surgical Tool ◽

Surgical Simulations ◽

Tissue Deformations

The requirement of real time performance, crucial to multimodal surgical simulations, imposes severe demands in terms of computational efficiency. A physics-based meshfree computational technique known as the Point-Associated Finite Field (PAFF) approach has been developed to circumvent many outstanding problems associated with traditional mesh-based computational schemes and has been applied in this paper to the modeling of geometrically nonlinear tissue deformations. The technique is based on a novel combination of multiresolution approach coupled with a fast reanalysis scheme in which the response predicted by an underlying linear PAFF model is enhanced in the local neighborhood of the surgical tool-tip by a nonlinear model. We present performance comparisons of PAFF with traditional finite element models.

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