Application of a Ground Beam-Joint Topology Optimization Method for Multi-Piece Frame Structure Design

2008 ◽  
Vol 130 (8) ◽  
Author(s):  
Myung-Jin Kim ◽  
Gang-Won Jang ◽  
Yoon Young Kim
Keyword(s):  
Topology Optimization ◽  
Optimization Technique ◽  
Joint Stiffness ◽  
Optimization Method ◽  
Structure Design ◽  
Frame Structure ◽  
Optimal Layout ◽  
Design Variables ◽  
Discrete Values ◽  
Topology Optimization Method

When a multipiece frame structure is designed, not only its topological layout but also assembly locations should be determined. This paper presents a compliance-minimizing topology optimization technique to determine an optimal layout configuration and to suggest candidate assembly locations. The technique employs a ground beam-joint model and places candidate assembly joints where the values of joint stiffness are relatively small. The zero-length joint elements have varying stiffness controlled by real-valued design variables. Because joint stiffness values at the converged state can be utilized to select candidate assembly locations along with their strengths, the technique is extremely useful in multipiece frame structure design. Because structural properties of ground beams can have only discrete values or remain unchanged for optimization process, no poststructural modification is required in an actual manufacturing step.

Manufacturability-Oriented Ground Beam-Joint Topology Optimization for Multi-Piece Frame Structure Design

2007 ◽  
Author(s):  
Myung-Jin Kim ◽  
Gang-Won Jang ◽  
Yoon Young Kim
Keyword(s):  
Topology Optimization ◽  
Structural Modification ◽  
Joint Stiffness ◽  
Structure Design ◽  
Design Tool ◽  
Frame Structure ◽  
Structural Performance ◽  
Beam Model ◽  
Optimal Layout ◽  
Design Variables

Topology optimization is a useful design tool, but it often yields layouts difficult to manufacture without considerable post structural modification. As a result, its structural performance can be significantly deteriorated. To minimize the undesirable postprocessing, we aim to develop a manufacturability-oriented compliance-minimizing topology optimization using a ground beam model incorporating additional zero-length elastic joint elements. In the present formulation, design variables control the stiffness of zero-length elastic joints, not the stiffness of beams. Because joint stiffness values at the converged state can be utilized to select candidate assembly locations, the technique is extremely useful to design multi-piece frame structures. An optimal layout is also extracted based on the stiffness values. Because structural properties of ground beams can take only on discretely available values or remain unchanged for optimization process, no post structural modification is required in an actual manufacturing step.

scholarly journals Topology Optimization of Hard-Coating Thin Plate for Maximizing Modal Loss Factors

Coatings ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 774
Author(s):  
Haitao Luo ◽  
Rong Chen ◽  
Siwei Guo ◽  
Jia Fu
Keyword(s):  
Topology Optimization ◽  
Objective Function ◽  
Composite Plates ◽  
Optimization Method ◽  
Hard Coating ◽  
Design Variables ◽  
Coating Composite ◽  
Damping Materials ◽  
Topology Optimization Method ◽  
Loss Factors

At present, hard coating structures are widely studied as a new passive damping method. Generally, the hard coating material is completely covered on the surface of the thin-walled structure, but the local coverage cannot only achieve better vibration reduction effect, but also save the material and processing costs. In this paper, a topology optimization method for hard coated composite plates is proposed to maximize the modal loss factors. The finite element dynamic model of hard coating composite plate is established. The topology optimization model is established with the energy ratio of hard coating layer to base layer as the objective function and the amount of damping material as the constraint condition. The sensitivity expression of the objective function to the design variables is derived, and the iteration of the design variables is realized by the Method of Moving Asymptote (MMA). Several numerical examples are provided to demonstrate that this method can obtain the optimal layout of damping materials for hard coating composite plates. The results show that the damping materials are mainly distributed in the area where the stored modal strain energy is large, which is consistent with the traditional design method. Finally, based on the numerical results, the experimental study of local hard coating composites plate is carried out. The results show that the topology optimization method can significantly reduce the frequency response amplitude while reducing the amount of damping materials, which shows the feasibility and effectiveness of the method.

scholarly journals Lightweight Design of Front Suspension Upright of Electric Formula Car Based on Topology Optimization Method

2020 ◽  
Vol 11 (1) ◽  
pp. 15 ◽  
Author(s):  
Jixiong Li ◽  
Jianliang Tan ◽  
Jianbin Dong
Keyword(s):  
Topology Optimization ◽  
Optimization Design ◽  
Lightweight Design ◽  
Geometric Model ◽  
Load Condition ◽  
Optimization Method ◽  
Structure Design ◽  
Front Suspension ◽  
Emergency Braking ◽  
Topology Optimization Method

In order to obtain a lightweight front upright of an electric formula car’s suspension, the topology optimization method is used in the front upright structure design. The mathematical model of the lightweight optimization design is constructed, and the geometric model of the initial design of the front upright is subjected to the ultimate load condition. The structural optimization of a front upright resulted in the mass reduction of the upright by 60.43%. The optimized model was simulated and verified regarding the strength, stiffness, and safety factor under three different conditions, namely turning braking, emergency braking, and sharp turning. In the experiment, the uprights were machined and assembled and integrated into the racing suspension. The experimental results showed that the optimized front uprights met the requirements of performance.

BIOMIMETIC STRUCTURE DESIGN OF DRAGONFLY WING VENATION USING TOPOLOGY OPTIMIZATION METHOD

2014 ◽  
Vol 14 (04) ◽  
pp. 1450078 ◽  
Author(s):  
JIYU SUN ◽  
MINGZE LING ◽  
CHUNXIANG PAN ◽  
DONGHUI CHEN ◽  
JIN TONG ◽  
...  
Keyword(s):  
Topology Optimization ◽  
Optimization Method ◽  
Structure Design ◽  
Staggered Grid ◽  
Wing Venation ◽  
Quantitative Models ◽  
Dragonfly Wing ◽  
Wing Motion ◽  
Dragonfly Wings ◽  
Topology Optimization Method

Scientists have carried out research for various biomimetic applications based on the dragonfly wings because of the superb flying skills and lightsome posture. The wings of dragonflies are mainly composed of veins and membranes, which give rise to the special characteristics of their wings that make dragonflies being supremely versatile, maneuverable fliers. Mimicking the dragonfly wing motion is of great technological interest from application's point of view. However, the major challenge is the biomimetic fabrication to replicate the wing motion due to the very complex nature of the wing venation of dragonfly wings. In this regard, the topology optimization method (TOM) is useful to simplify object's structure while retaining its mechanical properties. In this paper, TOM is employed to simplify and optimize the venation structure of dragonfly (Pantala flavescens Fabricius) wing that is captured by a 3D scanner and numerical reconfiguration. Combined with the material parameters obtained from nanoindentation testing, the quantitative models are established based on a finite element (FE) analysis and discussed in static range. The quantitative models are then compared with the square frame, staggered grid frame and hexagonal frame to examine the potentials of the biomimetic structure design for the fabrication of greenhouse roof.

Bridging Topological Results and Thin-Walled Frame Structures Considering Manufacturability

2021 ◽  
Vol 143 (9) ◽  
Author(s):  
Jiantao Bai ◽  
Yanfang Zhao ◽  
Guangwei Meng ◽  
Wenjie Zuo
Keyword(s):  
Topology Optimization ◽  
Cross Section ◽  
Structural Complexity ◽  
Optimization Method ◽  
Frame Structure ◽  
Frame Structures ◽  
Manufacturing Constraints ◽  
Numerical Examples ◽  
Thin Walled ◽  
Topology Optimization Method

Abstract Topology optimization has been intensively studied and extensively applied in engineering design. However, the optimized results often take the form of a solid frame structure; hence, it is difficult to apply the topological results in the design of a thin-walled frame structure. Therefore, this paper proposes a novel bridging method to transform the topological results into a lightweight thin-walled frame structure while satisfying the stiffness and manufacturing requirements. First, the optimized topological results are obtained using the classical topology optimization method, which is smoothed to reduce structural complexity. Then, the initial thin-walled frame structure is created by referring to the smoothed topological results, in which the thin-walled cross section is designed according to the mechanical properties and manufacturing requirements. Furthermore, the size and shape of the thin-walled frame structure is optimized to minimize mass with the stiffness and manufacturing constraints. Finally, numerical examples demonstrate that the proposed method can reasonably design an optimized thin-walled frame structure from the topological results.

STUDY ON MODAL TOPOLOGY OPTIMIZATION METHOD OF CONTINUUM STRUCTURE BASED ON EFG METHOD

2012 ◽  
Vol 09 (01) ◽  
pp. 1240005 ◽  
Author(s):  
SHUGUANG GONG ◽  
MIN CHEN ◽  
JIANPING ZHANG ◽  
RONG HE
Keyword(s):  
Topology Optimization ◽  
Optimization Method ◽  
Optimality Criteria ◽  
Differential Method ◽  
Gauss Point ◽  
Design Variables ◽  
Continuum Structure ◽  
Nodal Density ◽  
Element Free ◽  
Topology Optimization Method

The modal topology optimization method of continuum structure based on element-free Galerkin (EFG) method is presented by integrating solid isotropic material with penalization (SIMP) method with the optimality criteria method, and the penalty method is used to impose essential boundary conditions. The density of Gauss point and nodal density are selected as the design variables respectively, and the maximum of the first-order natural frequency is specified as the objective function. The sensitivity analysis algorithm is derived by using direct differential method. The examples are finished by selecting the two types of design variables respectively. The results obtained show that the checkerboard phenomenon does not appear when nodal density is selected as the design variable, and also verify that topology optimization method presented is feasible.

A Topology Optimization Method in Fuselage Flutter Model Design

2011 ◽  
Vol 199-200 ◽  
pp. 1297-1302
Author(s):  
Rui Yang ◽  
Yang Liu ◽  
Liang Zhou
Keyword(s):  
Inverse Problem ◽  
Topology Optimization ◽  
Natural Frequencies ◽  
Optimization Method ◽  
Frame Structure ◽  
Scale Model ◽  
Original Structure ◽  
Model Design ◽  
Structural Topology ◽  
Topology Optimization Method

Airplane flutter scale model should maintain the load transfer characteristics of the original structure. It is a structural inverse problem for proper natural frequencies as well as structural simplification. This inverse problem could be solved by topology optimization. So based on bi-direction evolutionary structural optimization (BESO) method, a topology method for designing fuselage flutter model is presented. Facing porous and irregular shape often appears in topology optimization, a regular shaped grid frame structure consisted of the finite elements is discussed, including its internal mapping relationship and boundary conditions. The ratio criterion for structural modification is raised in this structural topology optimization using frequency sensitivity. Finally, this topology optimization method is applied to cylindrical fuselage flutter model design, result shown that the proposed approach is feasible to achieve given natural frequencies, maintains the character of inner frame structure completely, and the similarity between optimized structure and original structure is achieved.

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