基于二阶响应面法的车辆转向机构稳健设计

综合考虑转向机构存在的不确定性运动误差,运用正交试验方法对某型车整体式转向机构进行了设计研究。以转向梯形臂长度、转向梯形底角为设计变量,以主销内倾角、主销后倾角、前轮外倾角和前轮前束为噪声因素,建立了基于二阶响应面的转向机构模型,并应用该模型对其进行了优化设计。通过与传统方法的结果对比,验证了本方法的先进性和有效性,为汽车转向机构的设计提供了新的方法。     

基于二阶响应面法的车辆转向机构稳健设计

综合考虑转向机构存在的不确定性运动误差,运用正交试验方法对某型车整体式转向机构进行了设计研究。以转向梯形臂长度、转向梯形底角为设计变量,以主销内倾角、主销后倾角、前轮外倾角和前轮前束为噪声因素,建立了基于二阶响应面的转向机构模型,并应用该模型对其进行了优化设计。通过与传统方法的结果对比,验证了本方法的先进性和有效性,为汽车转向机构的设计提供了新的方法。     

工程稳健设计

本文论述了工程稳健设计的基本概念和方法,介绍了稳健设计的几种主要方法及其发展趋势。     

基于双响应面模型的6σ稳健设计

双响应面法是通过试验设计分别构造响应均值和方差的近似模型，并通过该模型进行优化的一种稳健设计方法。文中对实验设计方法、响应曲面模型建立以及优化策略等进行分析。为实现质量管理与产品设计的协调，将质量工程中的6σ理念与双响应面法相结合，提出基于双响应面模型的6σ稳健优化设计方法。与传统优化方法相比，该方法不仅提高了优化效率，而且提高了设计的可靠性和稳健性。将其应用于结构优化设计和金属板料的拉深成形优化设计，均获得良好的结果。     

基于响应面法的数控磨床立柱热特性有限元模型修正

提出基于数控磨床立柱热变形检测与有限元模型分析相结合的一种有限元模型修正方法。将数控磨床立柱热特性位移误差与热载荷参数之间的隐形关系用显示函数近似表达出来,代替原有的有限元模型。在此基础上对有限元模型进行优化,提高有限元模型准确度。对数控磨床立柱有限元模型修正的结果表明,基于响应面模型的数控磨床立柱热特性有限元模型修正方法可以快速有效地修正模型,且修正结果精度高。     

基于响应面模型的刀口金属密封结构稳健设计

密封是危险品包装容器设计中的重要环节,合理确定密封结构设计参数是实现可靠密封的前提。基于有限元仿真,通过单因素数值试验分析,确定满足密封判据的刀口金属密封结构设计参数取值范围。采用均匀设计建立以设计参数为变量,有效密封面宽及最大接触压力为响应的二阶响应面模型,针对设计参数的扰动,结合多目标优化方法,在优化模型上增加表征目标函数稳健性的灵敏度附加项,并对约束条件进行稳健可行性调整,通过求解,得到结构较稳健的设计参数组合。     

基于响应面模型的永磁直流微电机堵转力矩稳健设计

以永磁直流微电机堵转力矩作为研究对象,应用响应面法中的等径设计进行参数设计,并对设计的方案进行了样机验证.结果表明:基于响应面模型的稳健设计是提高微电机质量的一种有效途径.     

基于响应面法的某防护结构优化设计

为提高某防护型驾驶室底部类V形防护结构对爆炸冲击波的防护性能,利用尺寸优化和形状优化相结合的设计方法,进行了防护结构的优化设计。首先通过拉丁超立方试验设计建立了中心防护板最大位移和模型总质量的高精度响应面;再综合考虑板件厚度和边界形状的变化范围以及安全性和轻量化要求,运用可行方向优化算法对建立的响应面进行了求解计算,得到了一组最优值。结果表明优化后防护结构的防护性能得到了显著提升,为更多防护结构的设计提供了参考依据。     

基于响应面法的微操作平台多目标优化

为了提高微操作平台的操作空间和动态性能,基于响应面法对一种新型微操作平台进行了多目标优化设计。采用中心组合设计方法选取仿真试验点,根据试验点建立平台的参数化几何模型,应用软件ANSYS对平台进行静力学和模态分析得到其固有频率、位移放大倍数和最大应力的响应值。根据所得的仿真试验数据,采用最小二乘法和显著性检验建立反映平台性能指标的二阶多项式响应面模型。最后,计算了反映响应面拟合度的评价指标,验证了所建响应面模型的精确性。以微操作平台的放大倍数和固有频率为优化目标,强度为约束,建立了平台的多目标优化模型,采用多目标遗传算法对平台进行优化得到Pareto解集。从Pareto解集可知,固有频率与放大倍数之间是相互冲突的,故需权衡固有频率和放大倍数从Pareto解集选取最优解。比较优化前后平台的各性能指标可知,平台的固有频率增大了35.58%,放大倍数增大了2.33%,最大应力减小了38.97%,证明了提出的优化方法的有效性。     

基于响应面法的升降机滚筒线支架轻量化设计

为了降低重量,减少成本,提高市场竞争力,基于响应面法对某型具有弯曲导轨的连续式升降机进料滚筒线支架进行了轻量化设计。采用中心复合试验设计方法进行样本点的采集,利用有限元数值模拟技术获取样本点的响应值。根据所得数据,构建了支架质量和最大等效应力的二阶多项式响应面模型,并进行了精度检验,验证了所构建响应面模型的精确性。以支架质量为目标,强度为约束,基于所构建的响应面模型,建立了支架轻量化设计数学模型,采用序列二次规划算法进行求解,并对优化结果进行了仿真验证。结果表明,优化后的支架强度满足要求,质量减少了11.7kg,减重率达42.5%,轻量化效果显著。     

A response surface based hierarchical approach to multidisciplinary robust optimization design

A multidisciplinary robust optimization design framework, concurrent subsystem robust design optimization, is proposed to obtain robust optimum solution in the large-scaled and coupled system. In this framework, response surfaces in the form of artificial neural networks provide information pertaining to system performance characteristics, and individual subsystems engage in performing robust optimization design in parallel while communicating with the system level. This optimization approach incorporates uncertainty analysis and generates a global robust optimum solution in an iterative fashion. Two applications are considered, and the results demonstrate that the approach yields a reasonable robust optimum solution, and it is a potential and efficient multidisciplinary robust optimization approach .     

Optimal design of high temperature vacuum furnace using response surface method

A new method using the response surface method and optimization technique has been developed instead of the original method based on trial and error. In order to construct a response surface, thermal analysis was performed under the condition of using the calculated thermal conductivity of the insulator in a previous study. In order to set up the response surface, the D-Optimal method was used in the process of selecting experimental points. Using a weighting factor, an optimization study was carried out under the condition of satisfying user requirements. Finally, the merits and drawbacks of the new method were described by comparing with the optimal design method based on the thermal analysis database which was developed in a previous study. The optimal results show that the developed method can be used to design an energy efficient, low manufacturing cost, high temperature vacuum furnace with avoiding unnecessary iterative manufacturing, and anticipating the performance before manufacturing. This paper was recommended for publication in revised form by Associate Editor Ohchae Kwon     

Gear hot forging process robust design based on finite element method

During the hot forging process, the shaping property and forging quality will fluctuate because of die wear, manufacturing tolerance, dimensional variation caused by temperature and the different friction conditions, etc. In order to control this variation in performance and to optimize the process parameters, a robust design method is proposed in this paper, based on the finite element method for the hot forging process. During the robust design process, the Taguchi method is the basic robust theory. The finite element analysis is incorporated in order to simulate the hot forging process. In addition, in order to calculate the objective function value, an orthogonal design method is selected to arrange experiments and collect sample points. The ANOVA method is employed to analyze the relationships of the design parameters and design objectives and to find the best parameters. Finally, a case study for the gear hot forging process is conducted. With the objective to reduce the forging force and its variation, the robust design mathematical model is established. The optimal design parameters obtained from this study indicate that the forging force has been reduced and its variation has been controlled.     

Optimal design of a variable stiffness joint in a robot manipulator using the response surface method

The response surface method combined with the design of experiment-based design optimization of a variable stiffness joint (VSJ) is presented in this article. A VSJ used in a manipulator of a robot arm to support 1 kg payload at the end is designed by considering the minimization of the total weight as the objective function. Owing to the requirement of large rotational stiffness of the VSJ, over 10 N · m, ring-type permanent magnets are adopted. First, a model composed of two permanent magnets was initially manufactured and tested for comparison with the analysis results. Then, a three-ring-type permanent magnet-based model is suggested and optimized to increase the torque of VSJ. The finite element method is used as a magnetic field analysis method to substitute for the expensive experimental process. Optimization results decrease the weight from 0.899 kg to 0.538 kg, still satisfying the requirement for the rotational stiffness. This paper was recommended for publication in revised form by Associate Editor Tae Hee Lee Jeonghoon Yoo received his B.S. and M.S. degrees in Mechanical Design and Production Engineering from Seoul National University, in 1989 and 1991, respectively. He then received his Ph.D. degrees from the University of Michigan, Ann Arbor, in 1999. Dr. Yoo is currently a Professor at the School of Mechanical Engineering at Yonsei University in Seoul, Korea. Dr. Yoo’s research interests include analysis and design of electromagnetic field systems. Myung Wook Hyun received his B.S. and M.S. degrees in Mechanical Engineering from Yonsei University, Korea, in 1995 and 1997, respectively. While studying for his M.S. degree, Mr. Hyun also studied variable stiffness unit design. He is now working at Samsung Electronics, Co. Ltd.. Jun Ho Choi received his B.S. and M.S. degrees in Mechanical Design from Hanyang University, Korea and his Ph.D. degree from the University of Michigan, Ann Arbor. He is currently a senior research scientist in the Korea Institute of Science and Technology. His research interests include nonlinear control, manipulator control, and safe-joint design. Sungchul Kang received his B.S., M.S., and Ph.D. degrees in Mechanical Design and Production Engineering from Seoul National University, Korea, in 1989, 1991, and 1998 respectively. Dr. Kang is currently a Principal Research Scientist in the Center for Cognitive Robotics Research, Korea Institute of Science and Technology, in Seoul, Korea. Dr. Kang’s research interests include mobility and manipulation of field and service robots and haptics. Seung-Jong Kim received his B.S. degree in Mechanical Engineering from Seoul University, Korea, in 1989, and his M.S. and Ph.D. degrees from KAIST in 1991 and 1998, respectively. Dr. Kim is currently a Principal Research Scientist at the Korea Institute of Science and Technology in Seoul, Korea. Dr. Kim’s research interests include the design, control, and dynamic analysis of mechatronic systems.     

The response surface method and the analysis of mild oxidational wear

Instead of using the conventional oxidation theory to depict a disk’s wear rate as a function of contact temperature, the response surface method (RSM) is herein introduced to relieve the one-factor-at-a-time defect in portraying tribological characteristics. By means of a central composite design (CCD) technique, fewer operating conditions are needed to establish expressions for the wear rate parameter, the contact temperature and the friction coefficient as a function of sliding speed and applied load. A second degree polynomial was used to represent a curved surface which fits the experimental data. In addition to results for the designated operating conditions, wear rate parameters and contact temperatures obtained from the polynomials were compared with the experimental results. The activation energy in the wear rate expression can thus be derived as a function of sliding speed, applied load and contact temperature. The experimental data for the wear rate parameter can be expressed by smooth curves, instead of two different straight lines in two temperature subdivisions.     

A study on the optimization method for a multi-body system using the response surface analysis

An optimization method, which minimizes the characteristic value of a system using response surface analysis, is presented. Plackett-Burman design is used as a screening method. Using the response surface analysis, second order recursive model function is estimated as an objective function. To verify the reliability of the model function, an F-test based on the analysis of variances table is used. Lastly, the sequential quadratic-programming method is used to find the value of design parameters. By applying the preceding procedure to a multi-body dynamic model, the optimization process presented in this study is verified. This paper was presented at the 4th Asian Conference on Multibody Dynamics(ACMD2008), Jeju, Korea, August 20–23, 2008. Sung Pil Jung received a B.S. degree in Mechanical Engineering from Ajou University in 2006. Currently he is a Ph.D candidate at Ajou University in Suwon, Korea. Mr. Jung’s research interests are in the area of multi-body & structural dynamics, optimization and computer aided engineering. Tae Won Park received a B.S. degree in Mechanical Engineering from Seoul University. He then went on to receive his M.S. and Ph.D. degrees from the University of Iowa. Dr. Park is currently a Professor at the School of Mechanical Engineering at Ajou University in Suwon, Korea.     

Global optimization method using SLE and adaptive RBF based on fuzzy clustering

High fidelity analysis models,which are beneficial to improving the design quality,have been more and more widely utilized in the modern engineering design optimization problems.However,the high fidelity analysis models are so computationally expensive that the time required in design optimization is usually unacceptable.In order to improve the efficiency of optimization involving high fidelity analysis models,the optimization efficiency can be upgraded through applying surrogates to approximate the computationally expensive models,which can greately reduce the computation time.An efficient heuristic global optimization method using adaptive radial basis function(RBF) based on fuzzy clustering(ARFC) is proposed.In this method,a novel algorithm of maximin Latin hypercube design using successive local enumeration(SLE) is employed to obtain sample points with good performance in both space-filling and projective uniformity properties,which does a great deal of good to metamodels accuracy.RBF method is adopted for constructing the metamodels,and with the increasing the number of sample points the approximation accuracy of RBF is gradually enhanced.The fuzzy c-means clustering method is applied to identify the reduced attractive regions in the original design space.The numerical benchmark examples are used for validating the performance of ARFC.The results demonstrates that for most application examples the global optima are effectively obtained and comparison with adaptive response surface method(ARSM) proves that the proposed method can intuitively capture promising design regions and can efficiently identify the global or near-global design optimum.This method improves the efficiency and global convergence of the optimization problems,and gives a new optimization strategy for engineering design optimization problems involving computationally expensive models.     

基于拉丁超立方抽样及响应面的结构模糊分析

在对边值模糊分析方法和优化边值模糊分析方法研究的基础上,将拉丁超立方抽样和响应面方法引入结构模糊分析,提出一种基于拉丁超立方抽样及响应面的模糊分析方法。讨论这种方法的数学运算,并与Monte Carlo方法进行比较。最后基于这种方法,对一个用隐式方程描述的有限元悬臂梁模型进行模糊分析,得到变形模糊结果。     

Optimization of drawbead design in sheet forming using one step finite element method coupled with response surface methodology

In a sheet forming process, drawbead plays an important role on the control of the material flow. In this paper, a numerical procedure for the design of forming processes is described. It is based on the coupling of an optimization technique and the simplified one step finite element method (also called inverse approach). The optimization technique allows adjustment of the process parameters so that specified criteria are fulfilled. Response surface methodology (RSM) is a global approximation method, which is ideally suited for solving highly nonlinear optimization problems. The finite element method, in addition to predicting the response of the process to certain parameters, allows assessment of the effect of a variation in these parameters on this response. The authors utilize the one step method at the preliminary design stage to supply stress or strain information for the following optimization using RSM. The procedure for this optimization process is fully described. The front fender for Numisheet 2002 is presented and the real defect free workpiece is produced to demonstrate the usefulness of the proposed optimization procedure. A comparison between the two forming limit curves (FLC) before and after optimization and results obtained using the precise incremental commercial software DYNAFORM based on the explicit dynamic approach verify that the optimization design method of drawbead could be successfully applied in designing actual tools of auto body cover panels.