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Nonlinear stiffness optimization with prescribed deformed geometry and loads

Fan, Zhirui LU ; Yan, Jun ; Wallin, Mathias LU ; Ristinmaa, Matti LU orcid ; Niu, Bin ; Mooney, Sean and Zhao, Guozhong (2022) In Structural and Multidisciplinary Optimization 65(2).
Abstract

Optimization based on traditional forward motion analysis to ensure a prescribed load distribution on a deformed geometry is challenging, since the load distribution is highly coupled to the deformed geometry, boundary conditions, and the optimized material layout. In contrast to traditional forward motion analysis, the deformed configuration is prescribed in the inverse motion analysis, and the undeformed configuration is the outcome of the analysis. Consequently, the inverse motion analysis is able to define an exact deformed geometry. In the present study, we make use of this key advantage to design structures with both an exact deformed geometry and a prescribed load distribution. The objective in the optimization is to minimize a... (More)

Optimization based on traditional forward motion analysis to ensure a prescribed load distribution on a deformed geometry is challenging, since the load distribution is highly coupled to the deformed geometry, boundary conditions, and the optimized material layout. In contrast to traditional forward motion analysis, the deformed configuration is prescribed in the inverse motion analysis, and the undeformed configuration is the outcome of the analysis. Consequently, the inverse motion analysis is able to define an exact deformed geometry. In the present study, we make use of this key advantage to design structures with both an exact deformed geometry and a prescribed load distribution. The objective in the optimization is to minimize a general function of the nodal displacement vector. To formulate a well-posed optimization problem, the design is regularized using the partial differential equation filter and the sensitivity analysis is based on the adjoint method. The computational model is developed for neo-Hookean hyper-elasticity and the balance equations are discretized using the finite element method. The resulting nonlinear equations are solved using a conventional Newton–Raphson scheme. In the numerical examples, a cantilever beam with an embedded perfect circular shape is first considered. Next, a 2D gasket-like structure is designed, and finally, we consider a 3D structure with contact-like boundary conditions. In these examples, the prescribed deformed geometry is subject to a distributed external force. The examples show that the deformed geometry and load distribution can be exactly prescribed through stiffness optimization based on the inverse motion analysis.

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author
; ; ; ; ; and
organization
publishing date
type
Contribution to journal
publication status
published
subject
keywords
Finite strain, Geometric control, Inverse motion, Load distribution, Nonlinear finite element analysis, Topology optimization
in
Structural and Multidisciplinary Optimization
volume
65
issue
2
article number
67
publisher
Springer
external identifiers
  • scopus:85124029885
ISSN
1615-147X
DOI
10.1007/s00158-021-03167-9
language
English
LU publication?
yes
id
3921bab9-d526-4b1c-897f-1cc38a5b78d5
date added to LUP
2022-04-07 13:45:17
date last changed
2022-04-22 22:51:10
@article{3921bab9-d526-4b1c-897f-1cc38a5b78d5,
  abstract     = {{<p>Optimization based on traditional forward motion analysis to ensure a prescribed load distribution on a deformed geometry is challenging, since the load distribution is highly coupled to the deformed geometry, boundary conditions, and the optimized material layout. In contrast to traditional forward motion analysis, the deformed configuration is prescribed in the inverse motion analysis, and the undeformed configuration is the outcome of the analysis. Consequently, the inverse motion analysis is able to define an exact deformed geometry. In the present study, we make use of this key advantage to design structures with both an exact deformed geometry and a prescribed load distribution. The objective in the optimization is to minimize a general function of the nodal displacement vector. To formulate a well-posed optimization problem, the design is regularized using the partial differential equation filter and the sensitivity analysis is based on the adjoint method. The computational model is developed for neo-Hookean hyper-elasticity and the balance equations are discretized using the finite element method. The resulting nonlinear equations are solved using a conventional Newton–Raphson scheme. In the numerical examples, a cantilever beam with an embedded perfect circular shape is first considered. Next, a 2D gasket-like structure is designed, and finally, we consider a 3D structure with contact-like boundary conditions. In these examples, the prescribed deformed geometry is subject to a distributed external force. The examples show that the deformed geometry and load distribution can be exactly prescribed through stiffness optimization based on the inverse motion analysis.</p>}},
  author       = {{Fan, Zhirui and Yan, Jun and Wallin, Mathias and Ristinmaa, Matti and Niu, Bin and Mooney, Sean and Zhao, Guozhong}},
  issn         = {{1615-147X}},
  keywords     = {{Finite strain; Geometric control; Inverse motion; Load distribution; Nonlinear finite element analysis; Topology optimization}},
  language     = {{eng}},
  number       = {{2}},
  publisher    = {{Springer}},
  series       = {{Structural and Multidisciplinary Optimization}},
  title        = {{Nonlinear stiffness optimization with prescribed deformed geometry and loads}},
  url          = {{http://dx.doi.org/10.1007/s00158-021-03167-9}},
  doi          = {{10.1007/s00158-021-03167-9}},
  volume       = {{65}},
  year         = {{2022}},
}