A structural optimization design for an aluminum-intensive vehicle

2003 ◽  
Vol 217 (9) ◽  
pp. 771-779 ◽  
Author(s):  
Dong-Chan Lee ◽  
Jeong-Ick Lee
Keyword(s):  
Structural Optimization ◽  
Optimization Design ◽  
Joint Stiffness ◽  
Optimization Procedure ◽  
Steel Structure ◽  
Torsional Stiffness ◽  
Production Parameter ◽  
Parameter Region ◽  
Vehicle Structure ◽  
Structural Responses

This paper describes an integrated structural optimization procedure using a multilevel decomposition technique and a domain mapping contour that can represent the production parameter region. At the upper level, the structural responses are represented in terms of global quantities, i.e. stiffness, stresses and weight. At the lower level, the structural responses are represented in terms of local quantities, i.e. the intermediate parameters or the detailed dimensions based on the production parameter region. This technique was applied to develop the aluminium vehicle structure. The crosssectional characteristics and joint stiffness of the vehicle structure are calculated from the vehicle structure model which is composed of shell-beam-spring elements. In comparison with the base model (steel structure), the bending stiffness and torsional stiffness of the developed aluminium vehicle structure increase by around 45 and 35 per cent respectively, and the weight reduction is around 30 per cent. The manufactured structure is also presented.

scholarly journals Structural Optimization Design of Ship Lock Heads on Soft Soil considering Time-Varying Effects of the Structure and Foundation

2021 ◽  
Vol 2021 ◽  
pp. 1-21
Author(s):  
Jiawei Bai ◽  
Chao Su ◽  
Heng Zhang ◽  
Shaopei Hu
Keyword(s):  
Structural Optimization ◽  
Optimization Design ◽  
Soft Soil ◽  
Optimization Procedure ◽  
Optimized Design ◽  
Time Varying ◽  
The Maximum Principle ◽  
Hybrid Particle Swarm Optimization ◽  
Whale Optimization ◽  
Ship Lock

Over time, the uneven settlements of the structure and foundation are prominent in constructing ship lock heads on soft soil. These deformations endanger the safety of ship lock heads during construction. This research aimed to establish the ship lock head’s structural optimization procedure on soft soil, considering the time-varying effects of the structure and foundation. By comprehensively considering the linear viscoelastic creep of concrete and the elastoplastic consolidation characteristic of soft soil, a perfect time-dependent analysis method for the lock head on soft soil was proposed. Furthermore, a hybrid particle swarm optimization, enhanced whale optimization, and differential evolution (PSO-EWOA-DE) algorithm was proposed to optimize thirty-four design variables of a lock head. With the minimal volume of the lock head as the optimization objective, the finite element model was established. In the optimization process, three types of constraints were evaluated. The result showed that the optimized design could reduce 10.45% of structure volume. Through comparing and analysing the maximum principle stresses and vertical displacements of the lock head before and after optimization, some conclusions were drawn. The optimization procedure proposed in this paper provides a new perspective for the structural optimization of hydraulic structures on soft soil.

Structural Optimization of Composite Panel with Lamination Parameters and Equivalent Stiffness Laminate Method

2014 ◽  
Vol 496-500 ◽  
pp. 429-435
Author(s):  
Xiao Ping Zhong ◽  
Peng Jin
Keyword(s):  
Genetic Algorithm ◽  
Structural Optimization ◽  
Composite Structure ◽  
Optimization Procedure ◽  
Optimization Method ◽  
Composite Panel ◽  
Analysis Tool ◽  
Equivalent Stiffness ◽  
Lamination Parameters ◽  
Design Variables

Firstly, a two-level optimization procedure for composite structure is investigated with lamination parameters as design variables and MSC.Nastran as analysis tool. The details using lamination parameters as MSC.Nastran input parameters are presented. Secondly, with a proper equivalent stiffness laminate built to substitute for the lamination parameters, a two-level optimization method based on the equivalent stiffness laminate is proposed. Compared with the lamination parameters-based method, the layer thicknesses of the equivalent stiffness laminate are adopted as continuous design variables at the first level. The corresponding lamination parameters are calculated from the optimal layer thicknesses. At the second level, genetic algorithm (GA) is applied to identify an optimal laminate configuration to target the lamination parameters obtained. The numerical example shows that the proposed method without considering constraints of lamination parameters can obtain better optimal results.

A New ERR and Strategy for Bi-Directional Evolutionary Structural Optimization

2012 ◽  
Vol 204-208 ◽  
pp. 4422-4428
Author(s):  
Da Ke Zhang ◽  
Wen Pan Zhang ◽  
Han He ◽  
Chong Wang
Keyword(s):  
Structural Optimization ◽  
Stress Level ◽  
Optimization Procedure ◽  
Optimal Process ◽  
Removal Ratio ◽  
Rejection Ratio ◽  
Evolutionary Structural Optimization ◽  
Rejection Criterion ◽  
Element Addition ◽  
Element Removal

The efficiency of the element removal or addition is of significance for evolutionary structural optimization (ESO) process. The key is to find an appropriate rejection criterion (RC) which allows to assess the contribution of each element to the specified behavior（stress, stiffness, displacement, etc.）of the structure, and to subsequently remove elements with least contribution. This paper proposed a varying elements removal ratio (VERR) method which uses a larger ERR (Element Rejection Ratio) value at early iterations where exist a lot of redundant material, and decreases the value of ERR in the optimal process to lessen the number of elements removed at later iterations. Meanwhile, this paper proposed a strategy for element addition based on stress level and the contribution of elements to the structure in order to decide which elements should be added to the model and the sequence of the element addition. With the proposed VERR and the strategy, the optimization procedure of the structure evolves more quickly and smoothly.

Structural Optimization Design of an Aircraft Metal-Composite Wing

2013 ◽  
Vol 341-342 ◽  
pp. 519-523
Author(s):  
Ya Hui Zhang ◽  
Ji Hong Zhu ◽  
Jun Shuo Li ◽  
Wei Hong Zhang
Keyword(s):  
Structural Optimization ◽  
Optimization Design ◽  
Optimization Method ◽  
Design Solution ◽  
Metal Composite ◽  
Concept Design ◽  
Obvious Effect ◽  
Reinforced Composite ◽  
Three Phase ◽  
Composite Wing

The problem of metal-composite wing structural optimization is discussed and a strategy is presented. Topology optimization method is applied to provide load transferring path of structure for concept design. Size, shape and other optimization method are used to provide detailed design for individual components. A three-phase optimization method is discussed for fiber reinforced composite laminate skin. Optimal parameters include ply angle, percentage, thickness, layer shape and sequence. The design of laminate for ease of manufacture is based on a set of manufacturing constraints. This paper deals with a total optimal design solution for aileron structure of an aircraft. The result satisfies all the requirements of strength and stability, and has obvious effect of weight loss.

Structural optimization design for antenna bracket manufactured by selective laser melting

2018 ◽  
Vol 24 (3) ◽  
pp. 539-547 ◽  
Author(s):  
Zefeng Xiao ◽  
Yongqiang Yang ◽  
Di Wang ◽  
Changhui Song ◽  
Yuchao Bai
Keyword(s):  
Structural Optimization ◽  
Modal Analysis ◽  
Selective Laser Melting ◽  
Optimization Model ◽  
Optimization Design ◽  
Analysis Data ◽  
Laser Melting ◽  
Design Rules ◽  
Content Type ◽  
Process Characteristics

Purpose This paper aims to summarize design rules based on the process characteristics of selective laser melting (SLM) and structural optimization and apply the design rules in the lightweight design of an aluminum alloy antenna bracket. The design goal is to reduce 30 per cent of the weight while maintaining the stress levels in the original part. Design/methodology/approach To reduce weight as much as possible, the titanium alloy with higher specific strength was selected during the process of optimization. The material distribution of the bracket was improved by the topology optimization design. The redesign for SLM was used to obtain an optimization model, which was more suitable for SLM. The component performance was improved by shape optimization. The modal analysis data of the structural optimization model were compared with those of the stochastic lightweight model to verify the structural optimization model. The scanning data were compared with those of the original model to verify whether the model was suitable for SLM. Findings Structural optimization design for antenna bracket realized the mass decrease of 30.43 per cent and the fundamental frequency increase of 50.18 per cent. The modal analysis data of the stochastic lightweight model and the structural optimization model indicated that the optimization performance of structural optimization method was better than that of the stochastic lightweight method. The comparison results between the scanning data of the forming part and the original data confirmed that the structural optimization design for SLM lightweight component could achieve the desired forming accuracy. Originality/value This paper summarizes geometric constraints in SLM and derives design rules of structural optimization based on the process characteristics of SLM. SLM design rules make structural optimization design more reasonable. The combination of structural optimization design and SLM can improve the performance of lightweight antenna bracket significantly.

Interactive Multiobjective Optimization Design Strategy for Decision Based Design

1999 ◽  
Author(s):  
Ravindra V. Tappeta ◽  
John E. Renaud
Keyword(s):  
Multiobjective Optimization ◽  
Optimization Design ◽  
Optimization Procedure ◽  
Design Strategy ◽  
Test Problems ◽  
Multi Objective Optimization ◽  
Original Algorithm ◽  
Multi Objective ◽  
Local Preference ◽  
Preference Functions

Abstract This research focuses on multi-objective system design and optimization. The primary goal is to develop and test a mathematically rigorous and efficient interactive multi-objective optimization algorithm that takes into account the Decision Maker’s (DM’s) preferences during the design process. An Interactive Multi-Objective Optimization Procedure (IMOOP) developed in [12] has been modified in this research to include the DM’s local preference functions in an Iterative Decision Making Strategy (IDMS). This enhanced multiobjective optimization procedure called the interactive MultiObjective Optimization Design Strategy (iMOODS) provides the DM with a formal means for efficient design exploration around a given Pareto point. The use of local preference functions allows the original algorithm [12] to be modified such that the second order Pareto surface approximation is more accurate in the preferred region of the Pareto surface. The iMOODS has been successfully applied to two test problems. The first problem consists of a set of simple analytical expressions for the objectives and constraints. The second problem is the design and sizing of a high-performance and low-cost ten bar structure that has multiple objectives. The results indicate that the class functions are effective in capturing the local preferences of the DM. The Pareto designs that reflect the DM’s preferences can be efficiently generated within IDMS.

Structural optimization design of large-aperture mirror for space remote sensing camera

2020 ◽  
Vol 49 (2) ◽  
pp. 214002
Author(s):  
张超杰 Zhang Chaojie ◽  
习兴华 Xi Xinghua ◽  
王永宪 Wang Yongxian ◽  
朱俊青 Zhu Junqing ◽  
关英俊 Guan Yingjun
Keyword(s):  
Remote Sensing ◽  
Structural Optimization ◽  
Optimization Design ◽  
Large Aperture

scholarly journals Rotation-joint stiffness modeling for industrial robots considering contacts

2018 ◽  
Vol 10 (8) ◽  
pp. 168781401879306 ◽  
Author(s):  
Zhifeng Liu ◽  
Jingjing Xu ◽  
Qiang Cheng ◽  
Yongsheng Zhao ◽  
Yanhu Pei
Keyword(s):  
Fractal Theory ◽  
Joint Stiffness ◽  
Industrial Robots ◽  
Torsional Stiffness ◽  
Equivalent Stiffness ◽  
Force Analysis ◽  
Joint System ◽  
End Effector ◽  
Stiffness Modeling ◽  
High Speeds

Joint flexibility has a major impact on the motion accuracy of a robotic end effector, particularly at high speeds. This work proposes a technique of precisely modeling the torsional stiffness of the rotational joints for the industrial robots. This technique considers the contacts that exist in the joint system, which can have a significant effect on the overall joint stiffness. The torsional stiffness of the connections that commonly exist in the rotational joints, such as the belt connection, the connections using key, bolts, and pins, were modeled by combining the force analysis and the fractal theory. Through modeling the equivalent stiffness for the springs in serial and in parallel, the torsional stiffness of all joints for the ER3A-C60 robot were calculated and analyzed. The results show that the estimated stiffness based on the proposed technique is closer to the actual values than that based on the previous model without considering the contacts. The analysis is useful for controlling the dynamic characteristic of the industrial robots with the rotational joints while planning the trajectory for the end effector.

Performance Based Optimized Design of Steel Structure

2014 ◽  
Vol 919-921 ◽  
pp. 199-202
Author(s):  
Lan Lan Zhang ◽  
Xiao Guang Song ◽  
Jing Juan Zhang
Keyword(s):  
Optimization Design ◽  
Design Principle ◽  
Steel Structure ◽  
Steel Structures ◽  
Construction Cost ◽  
Optimized Design ◽  
Structural System ◽  
Sizing Optimization ◽  
The Past ◽  
Whole Process

During the past two centuries, steel structure has become one of the most popular structural system. How to balance the construction cost, structural properties and other factors is an important aspect needed to be addressed. This paper describes the whole process of performance based optimized design of steel structure. First, the methods on the shape and sizing optimization, cost and others are introduced. Then, the multi-object optimization of steel structure is presented, in which the main aspects of the optimizations are studied. Finally, the design principle and the analytical steps for the multi-object optimization of steel structures are discussed. This paper can be references for the optimization design of steel structures.

Sign in / Sign up

Export Citation Format

Share Document