Discrete sizing, cross-sectional shape, topology optimization, and material selection of a framed automotive body

2021 ◽  
pp. 095440702110626
Author(s):  
Chao Ma
Keyword(s):  
Weight Reduction ◽  
Material Selection ◽  
Extreme Points ◽  
Optimization Method ◽  
Test Problems ◽  
Manufacturing Cost ◽  
Cross Sectional ◽  
Automotive Body ◽  
Discrete Design Variables ◽  
Sectional Shape

This study proposed a discrete structural optimization method for a framed automotive body. Up to four types of discrete design variables are considered simultaneously, that is, the sizing, cross-sectional shape, topology, and material variables. Firstly, to solve the nonconvex and nonlinear optimization problem, the original non-dominated sorting genetic algorithm, the third version (NSGA-III), is adapted. An improved extreme points identification scheme and a new mutation operator are proposed to stabilize the normalization of the population and accommodate the manufacturing constraints, respectively. Two test problems demonstrate that the modified NSGA-III can handle continuous and discontinuous multiple objective optimization. Subsequently, the classical 10-bar truss is used to illustrate the proposed method. A weight reduction of 4.5 kg is achieved as compared to previous optimal designs in the literature. Finally, a framed automotive body is optimized for maximizing the first order natural frequency and minimizing the total mass, the maximum stresses and the maximum displacements in different load cases and the manufacturing cost. The results obtained by different optimization procedures are presented and discussed. The results demonstrate the feasibility and effectiveness of the proposed method. A weight reduction of 17.59% is achieved while other structural performances satisfy the design requirements.

A Multiple Cross-Sectional Shape Optimization Method for Automotive Body Frames

2005 ◽  
Vol 127 (1) ◽  
pp. 49-57 ◽  
Author(s):  
Masataka Yoshimura ◽  
Shinji Nishiwaki ◽  
Kazuhiro Izui
Keyword(s):  
Optimization Problem ◽  
Optimization Method ◽  
Continuous Variables ◽  
Cross Sectional ◽  
Automotive Body ◽  
Generating Method ◽  
Metal Sheets ◽  
Discrete Design Variables ◽  
The Cross ◽  
Sectional Shape

Automotive body frames, which profoundly affect automotive performance such as crashworthiness, are generally formed using pressed metal sheets, and the assembled cross-sectional shapes govern the frame characteristics. This paper proposes a cross-sectional shape generating method for achieving the cross-sectional properties assigned by design engineers. The cross-sectional shape-generating problem for pressed metal sheets is formulated as a multiobjective optimization problem that involves a marriage of continuous variables, such as shape dimensions, and discrete design variables, such as types of material and their thicknesses. Genetic algorithms are applied to solve the optimization problem.

A Structural Topology Optimization Method Using Beam Elements : Effect of Cross-Sectional Shape of Beam

2002 ◽  
Vol 2002.5 (0) ◽  
pp. 135-140
Author(s):  
Shinji Nishiwaki ◽  
Hidekazu Nishigaki ◽  
Yasuaki Tsurumi ◽  
Yoshio Kojima ◽  
Noboru Kikuchi ◽  
...  
Keyword(s):  
Topology Optimization ◽  
Optimization Method ◽  
Structural Topology Optimization ◽  
Structural Topology ◽  
Cross Sectional ◽  
Beam Elements ◽  
Sectional Shape ◽  
Topology Optimization Method

A Concurrent Design Method for Multiple Cross-Sectional Automotive Body Frames Involving Discrete and Continuous Design Variables

2003 ◽  
Author(s):  
Masataka Yoshimura ◽  
Shinji Nishiwaki ◽  
Kazuhiro Izui
Keyword(s):  
Design Process ◽  
Design Method ◽  
Analytical Models ◽  
Cross Sectional ◽  
Automotive Body ◽  
Initial Design ◽  
Design Variables ◽  
Mechanical Products ◽  
Cross Sectional Design ◽  
Sectional Shape

As CAE (Computer Aided Engineering) applications become increasingly precise, the knowledge and technical skill required to operate such applications has become more highly specialized. However, such tools have not been utilized in the initial design process of mechanical products, where designers cannot construct detailed analytical models. This paper proposes a cross-sectional shape design optimization system that supports the initial design process for bar structures. The cross-sectional design problem is formulated as an eight-objective optimization problem that can be solved using genetic algorithms. A method for generating cross-sectional shapes satisfying designer-required characteristics is also proposed. These methods, which reduce the number of trial and error processes and product design failures, are expected to enable shortened product development lead-times.

scholarly journals Optimization and Experimental Study of the Subsea Retractable Connector Rubber Packer based on Mooney-Rivlin Constitutive Model

2021 ◽  
Vol 9 (12) ◽  
pp. 1391
Author(s):  
Kefeng Jiao ◽  
Feihong Yun ◽  
Zheping Yan ◽  
Gang Wang ◽  
Peng Jia ◽  
...  
Keyword(s):  
Structural Parameters ◽  
Optimization Method ◽  
Cross Sectional ◽  
Factors Affecting ◽  
Response Surface Optimization ◽  
Multi Objective Genetic Algorithm ◽  
Design Variables ◽  
Sealing Performance ◽  
The Cross ◽  
Sectional Shape

The sealing performance of the rubber packer is of vital importance for the subsea retractable connector, and the cross-sectional shape of the rubber packer is one of the most important factors affecting it. The compression distance of the rubber packer is increased by 19.54% utilizing the established two-dimensional numerical model. In addition, a new parameter called the anti-shoulder extrusion variable was defined in this paper. Shoulder extrusion will not occur when using this variable as a constraint during simulation. In general, the upper end and the lower end of a rubber packer are subject to different constraints, and the structural parameters of the rubber packer affect each other in terms of sealing performance. Therefore, the importance and originality of this study are exploring the optimization of the thickness and chamfer angles of the upper and lower ends of the rubber packer by use of a combination of the response surface optimization method and the multi-objective genetic algorithm, taking the thickness and chamfer angles of the upper and lower ends as design variables, and the stress on the inner side of the casing wall and the axial force of the compressed rubber packer as optimization objectives. Besides that, the anti-shoulder extrusion variables are also introduced as constraints to prevent shoulder extrusion. Ultimately, the cross-sectional shape of the rubber packer with a smaller-thickness and larger-angle upper end, and a larger-thickness and smaller-angle lower end can be obtained. The result to emerge from the test in this paper is that the pipe pressure that can be sealed by the optimized rubber packer structure is 25.61% higher than that before optimization. The anti-shoulder extrusion variable and the asymmetric cross-sectional shape of the rubber packer proposed in this paper shed new light on the finite element simulation of rubber and the research on similar seals.

On the cross-sectional shape of the cellulose crystallites in the tunicate Halocynthia papillosa

1990 ◽  
Vol 48 (3) ◽  
pp. 566-567
Author(s):  
J.-F. Revol ◽  
Y. Van Daele ◽  
F. Gaill
Keyword(s):  
Contrast Imaging ◽  
Animal Kingdom ◽  
Bright Field ◽  
Field Mode ◽  
Cross Sectional ◽  
Ultrathin Sections ◽  
The Cross ◽  
Sectional Shape ◽  
Valonia Ventricosa ◽  
C Nmr

The only form of cellulose which could unequivocally be ascribed to the animal kingdom is the tunicin that occurs in the tests of the tunicates. Recently, high-resolution solid-state l3C NMR revealed that tunicin belongs to the Iβ form of cellulose as opposed to the Iα form found in Valonia and bacterial celluloses. The high perfection of the tunicin crystallites led us to study its crosssectional shape and to compare it with the shape of those in Valonia ventricosa (V.v.), the goal being to relate the cross-section of cellulose crystallites with the two allomorphs Iα and Iβ.In the present work the source of tunicin was the test of the ascidian Halocvnthia papillosa (H.p.). Diffraction contrast imaging in the bright field mode was applied on ultrathin sections of the V.v. cell wall and H.p. test with cellulose crystallites perpendicular to the plane of the sections. The electron microscope, a Philips 400T, was operated at 120 kV in a low intensity beam condition.

Automated 3D measurement of fiber cross section morphology in handsheets

2012 ◽  
Vol 27 (2) ◽  
pp. 264-269 ◽  
Author(s):  
Christian Lorbach ◽  
Ulrich Hirn ◽  
Johannes Kritzinger ◽  
Wolfgang Bauer
Keyword(s):  
Image Analysis ◽  
Cross Section ◽  
Cross Sections ◽  
Image Plane ◽  
3D Measurement ◽  
Cross Sectional ◽  
Fiber Cross Section ◽  
Fiber Wall ◽  
Sectional Shape ◽  
Cross Section Geometry

Abstract We present a method for 3D measurement of fiber cross sectional morphology from handsheets. An automated procedure is used to acquire 3D datasets of fiber cross sectional images using an automated microtome and light microscopy. The fiber cross section geometry is extracted using digital image analysis. Simple sample preparation and highly automated image acquisition and image analysis are providing an efficient tool to analyze large samples. It is demonstrated that if fibers are tilted towards the image plane the images of fiber cross sections are always larger than the true fiber cross section geometry. In our analysis the tilting angles of the fibers to the image plane are measured. The resulting fiber cross sectional images are distorted to compensate the error due to fiber tilt, restoring the true fiber cross sectional shape. We use an approximated correction, the paper provides error estimates of the approximation. Measurement results for fiber wall thickness, fiber coarseness and fiber collapse are presented for one hardwood and one softwood pulp.

Weight Reduction of the Automotive Body by using Three-Dimensional Hot Bending and Direct Quench (3DQ) Technology

2015 ◽  
Vol 84 (7) ◽  
pp. 514-518
Author(s):  
Ryuji HAMADA ◽  
Hiroki FUJIMOTO ◽  
Masahiro OGAWA ◽  
Naoaki SHIMADA
Keyword(s):  
Weight Reduction ◽  
Three Dimensional ◽  
Automotive Body ◽  
Direct Quench

scholarly journals Lightweight and maintainable rotary-wing UAV frame from configurable design to detailed design

2021 ◽  
Vol 13 (7) ◽  
pp. 168781402110349
Author(s):  
Huiqiang Guo ◽  
Mingzhe Li ◽  
Pengfei Sun ◽  
Changfeng Zhao ◽  
Wenjie Zuo ◽  
...  
Keyword(s):  
Design Method ◽  
Geometric Model ◽  
Optimization Method ◽  
Frame Structure ◽  
Manufacturing Cost ◽  
Detailed Design ◽  
High Manufacturing Cost ◽  
The Military ◽  
Rotary Wing ◽  
Novel Design

Rotary-wing unmanned aerial vehicles (UAVs) are widespread in both the military and civilian applications. However, there are still some problems for the UAV design such as the long design period, high manufacturing cost, and difficulty in maintenance. Therefore, this paper proposes a novel design method to obtain a lightweight and maintainable UAV frame from configurable design to detailed design. First, configurable design is implemented to determine the initial design domain of the UAV frame. Second, topology optimization method based on inertia relief theory is used to transform the initial geometric model into the UAV frame structure. Third, process design is considered to improve the manufacturability and maintainability of the UAV frame. Finally, dynamic drop test is used to validate the crashworthiness of the UAV frame. Therefore, a lightweight UAV frame structure composed of thin-walled parts can be obtained and the design period can be greatly reduced via the proposed method.

Sign in / Sign up

Export Citation Format

Share Document