The modified quadrilateral discretization model for the topology optimization of compliant mechanisms is introduced in this paper. The design domain is discretized into quadrilateral design cells. There is a certain location shift between two neighboring rows of quadrilateral design cells. This modified quadrilateral discretization model allows any two contiguous design cells to share an edge whether they are in the horizontal, vertical, or diagonal direction. Point connection is completely eliminated. In the proposed topology optimization method, design variables are all binary, and every design cell is either solid or void to prevent gray cell problem that is usually caused by intermediate material states. Local stress constraint is directly imposed on each analysis cell to make the synthesized compliant mechanism safe. Genetic algorithm is used to search the optimum. No postprocessing is required for topology uncertainty caused by either point connection or gray cell. The presented modified quadrilateral discretization model and the proposed topology optimization procedure are demonstrated by two synthesis examples of compliant mechanisms.

References

1.
Yin
,
L.
, and
Ananthasuresh
,
G. K.
, 2003, “
Design of Distributed Compliant Mechanisms
,”
Mech. Based Des. Struct. Mach.
,
31
, pp.
151
179
.
2.
Howell
,
L. L.
, 2001,
Compliant Mechanisms
,
Wiley
,
NY
.
3.
Bendsoe
,
M. P.
, and
Kikuchi
,
N.
, 1988, “
Generating Optimal Topologies in Structural Design Using a Homogenization Method
,”
Comput. Methods Appl. Mech. Eng.
,
71
, pp.
197
224
.
4.
Sigmund
,
O.
, 1997, “
On the Design of Compliant Mechanisms Using Topology Optimization
,”
Mech. Struct. Mach.
,
25
, pp.
493
524
.
5.
Diaz
,
A. R.
, and
Sigmund
,
O.
, 1995, “
Checkerboard Patterns in Layout Optimization
,”
Struct. Optim.
,
10
, pp.
40
45
.
6.
Jog
,
C. S.
, and
Haber
,
R. B.
, 1996, “
Stability of Finite Element Models for Distributed Parameter Optimization and Topology Design
,”
Comput. Methods Appl. Mech. Eng.
,
130
, pp.
203
226
.
7.
Poulsen
,
T. A.
, 2002, “
A Simple Scheme to Prevent Checkerboard Patterns and One-Node Connected Hinges in Topology Optimization
,”
Struct. Multidiscip. Optim.
,
24
, pp.
396
399
.
8.
Poulsen
,
T. A.
, 2003, “
A New Scheme for Imposing a Minimum Length Scale in Topology Optimization
,”
Int. J. Numer. Methods Eng.
,
57
, pp.
741
760
.
9.
Pomezanski
,
V.
,
Querin
,
O. M.
, and
Rozvany
,
G. I. N.
, 2005, “
CO-SIMP: Extended SIMP Algorithm With Direct Corner Contact Control
,”
Struct. Multidiscip. Optim.
,
30
, pp.
164
168
.
10.
Haber
,
R. B.
,
Jog
,
S. C.
, and
Bendsoe
,
M. P.
, 1996, “
A New Approach to Variable-Topology Shape Design Using a Constraint on Perimeter
,”
Struct. Multidiscip. Optim.
,
11
, pp.
1
12
.
11.
Petersson
,
J.
, 1999, “
Some Convergence Results in Perimeter-Controlled Topology Optimization
,”
Comput. Methods Appl. Mech. Eng.
,
171
, pp.
123
140
.
12.
Petersson
,
J.
, and
Sigmund
,
O.
, 1998, “
Slope Constrained Topology Optimization
,”
Int. J. Numer. Methods Eng.
,
41
, pp.
1417
1434
.
13.
Zhou
,
M.
,
Shyy
,
Y. K.
, and
Thomas
,
H. L.
, 2001, “
Checkerboard and Minimum Member Size Control in Topology Optimization
,”
Struct. Multidiscip. Optim.
,
21
, pp.
152
158
.
14.
Jang
,
G. W.
,
Jeong
,
J. H.
,
Kim
,
Y. Y.
,
Sheen
,
D.
,
Park
,
C.
, and
Kim
,
M. N.
, 2003, “
Checkerboard-Free Topology Optimization Using Non-Conforming Finite Elements
,”
Int. J. Numer. Methods Eng.
,
57
, pp.
1717
1735
.
15.
Jang
,
G. W.
,
Lee
,
S.
,
Kim
,
Y. Y.
, and
Sheen
,
D.
, 2005, “
Topology Optimization Using Non-Conforming Finite Elements: Three-Dimensional Case
,”
Int. J. Numer. Methods Eng.
,
63
, pp.
859
875
.
16.
Belytschko
,
T.
,
Xiao
,
S. P.
, and
Parimi
,
C.
, 2003, “
Topology Optimization With Implicit Functions and Regulation
,”
Int. J. Numer. Methods Eng.
,
57
, pp.
1177
1196
.
17.
Rahmatalla
,
S. F.
, and
Swan
,
C. C.
, 2004, “
A Q4/Q4 Continuum Structural Topology Optimization Implementation
,”
Struct. Multidiscip. Optim.
,
27
, pp.
130
135
.
18.
Matsui
,
K.
, and
Terada
,
K.
, 2004, “
Continuous Approximation of Material Distribution for Topology Optimization
,”
Int. J. Numer. Methods Eng.
,
59
, pp.
1925
1944
.
19.
Guest
,
J. K.
,
Prevost
,
J. H.
, and
Belytschko
,
T.
, 2004, “
Achieving Minimum Length Scale in Topology Optimization Using Nodal Design Variables and Projection Functions
,”
Int. J. Numer. Methods Eng.
,
61
, pp.
238
254
.
20.
Saxena
,
A.
, 2008, “
A Material-Mask Overlay Strategy for Continuum Topology Optimization of Compliant Mechanisms Using Honeycomb Discretization
,”
ASME J. Mech. Des.
,
130
, p.
082304
.
21.
Jain
,
C.
, and
Saxena
,
A.
, 2010, “
An Improved Material-Mask Overlay Strategy for Topology Optimization of Structures and Compliant Mechanisms
,”
ASME J. Mech. Des.
,
132
, p.
061006
.
22.
Saxena
,
A.
, 2011, “
Are Circular Shaped Masks Adequate in Adaptive Mask Overlay Topology Synthesis Method?
,”
ASME J. Mech. Des.
,
133
, p.
011001
.
23.
Saxena
,
A.
, 2011, “
An Adaptive Material Mask Overlay Method: Modifications and Investigations on Binary, Well Connected Robust Compliant Continua
,”
ASME J. Mech. Des.
,
133
, p.
041004
.
24.
Zhou
,
H.
, 2010, “
Topology Optimization of Compliant Mechanisms Using Hybrid Discretization Model
,”
ASME J. Mech. Des.
,
132
, p.
111003
.
25.
Bendsoe
,
M. P.
, and
Sigmund
,
O.
, 2003,
Topology Optimization: Theory, Methods and Applications
,
Springer
,
NY
.
26.
Eschenauer
,
H. A.
, and
Olhoff
,
N.
, 2001, “
Topology Optimization of Continuum Structures: A Review
,”
Appl. Mech. Rev.
,
54
, pp.
331
389
.
27.
Rozvany
,
G. I. N.
, 2009, “
A Critical Review of Established Methods of Structural Topology Optimization
,”
Struct. Multidiscip. Optim.
,
37
, pp.
217
237
.
28.
Amstutz
,
S.
, and
Novotny
,
A. N.
, 2010, “
Topological Optimization of Structures Subject to von Mises Stress Constraints
,”
Struct. Multidiscip. Optim.
,
41
, pp.
407
422
.
29.
Chapman
,
C. D.
,
Saitou
,
K.
, and
Jakiela
,
M. J.
, 1994, “
Genetic Algorithms as an Approach to Configuration and Topology Design
,”
ASME J. Mech. Des.
,
116
, pp.
1005
1012
.
30.
Chandrupatla
,
T. R.
, and
Belegundu
,
A. D.
, 2004,
Introduction to Finite Elements in Engineering
,
Prentice-Hall
,
Englewood Cliffs, NJ
.
31.
Kattan
,
P. I.
, 2007,
MATLAB Guide to Finite Elements
,
Springer
.
32.
Goldberg
,
D. E.
, 1989,
Genetic Algorithms in Search, Optimization, and Machine Learning
,
Addison-Wesley
,
Boston, MA
.
33.
Kim
,
I. Y.
, and
Weck
,
O. L.
, 2005, “
Variable Chromosome Length Genetic Algorithm for Progressive Refinement in Topology Optimization
,”
Struct. Multidiscip. Optim.
,
29
, pp.
445
456
.
34.
Kim
,
D. S.
,
Jung
,
D. H.
, and
Kim
,
Y. Y.
, 2008, “
Multiscale Multiresolution Genetic Algorithm With a Golden Sectioned Population Composition
,”
Int. J. Numer. Methods Eng.
,
74
, pp.
349
367
.
35.
Chapman
,
C. D.
, and
Jakiela
,
M. J.
, 1996, “
Genetic Algorithm-Based Structural Topology Design With Compliance and Topology Simplification Considerations
,”
ASME J. Mech. Des.
,
118
, pp.
89
98
.
36.
Kane
,
C.
, and
Schoenauer
,
M.
, 1996, “
Topological Optimum Design Using Genetic Algorithms
,”
Contr. Cybernet.
,
25
, pp.
1059
1088
.
37.
Duda
,
J. W.
, and
Jakiela
,
M. J.
, 1997, “
Generation and Classification of Structural Topologies Genetic Algorithm Speciation
,”
ASME J. Mech. Des.
,
119
, pp.
127
131
.
38.
Deo
,
N.
, 1990,
Graph Theory With Applications to Engineering and Computer Science
,
Prentice-Hall
,
Englewood Cliffs, NJ
.
39.
Haupt
,
R. L.
, and
Haupt
,
S. E.
, 2004,
Practical Genetic Algorithms
, 2nd ed.,
Wiley
,
NY
.
40.
Zhou
,
H.
, and
Ting
,
K. L.
, 2006, “
Shape and Size Synthesis of Compliant Mechanisms Using Wide Curve Theory
,”
ASME J. Mech. Des.
,
128
, pp.
551
558
.
41.
Zhou
,
H.
, and
Ting
,
K. L.
, 2008, “
Geometric Modeling and Optimization of Multimaterial Compliant Mechanisms Using Multilayer Wide Curves
,”
ASME J. Mech. Des.
,
130
, p.
062303
.
42.
Zhou
,
H.
, and
Ting
,
K. L.
, 2009, “
Geometric Optimization of Spatial Compliant Mechanisms Using Three-Dimensional Wide Curves
,”
ASME J. Mech. Des.
,
131
,
051002
.
43.
Xu
,
D.
, and
Ananthasuresh
,
G. K.
, 2003, “
Freeform Skeletal Shape Optimization of Compliant Mechanisms
,”
ASME J. Mech. Des.
,
125
, pp.
253
261
.
You do not currently have access to this content.