• 대한기계학회:학술대회논문집
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• 대한기계학회 2004년도 추계학술대회
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• pp.870-875
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• 2004

Current trend of design technologies shows engineers to objectify or automate the given decision-making process. The numerical optimization is an example of such technologies. However, in numerical optimization, the uncertainties are uncontrollable to efficiently objectify or automate the process. To better manage these uncertainties, Taguchi method, reliability-based optimization and robust optimization are being used. To obtain the target performance with the maximum robustness is the main functional requirement of a mechanical system. In this research, the robust design strategy is developed based on the DACE and the global optimization approaches. The DACE modeling, known as the one of Kriging interpolation, is introduced to obtain the surrogate approximation model of the system. The robustness is determined by the DACE model to reduce the real function calculations. The simulated annealing algorithm of global optimization methods is adopted to determine the global robust design of a surrogated model. The mathematical problems and the MEMS design problem are investigated to show the validity of the proposed method.

• 한국소음진동공학회논문집
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• 제12권10호
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• pp.773-784
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• 2002

This paper proposes an optimal design to improve the performance of the intake system by reducing the noise. We adapt the Taguchi method and column merging method for the above design. At the first stage of the design, the length and radius of each component of the current intake system are selected as control factors. Then the $L^{18}$ table of orthogonal array is used to get the effective main factors. At the second stage, the $L^{16}$ table of orthogonal array and the column merging method is combined to analyze subdivided significant factors. We know that the robust design with the column merging method provides better design for noise of intake system than the robust design itself.

• 대한기계학회논문집
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• 제18권2호
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• pp.278-291
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• 1994

A computer-aided robust design (CARD) technique is developed to search for the design variables, optimal as well as robust in the sense of Taguchi method. The CARD technique can effectively handle inequality problems by employing the variable penalty method, and dynamic problems with many design variables and/or with mixed discrete and continuous variables. It is also capable of providing contributions of each design variables to the object funtion and information for future designs. As the illustrative examples, two dynamic systems, engine mounting system and in-line feeder, are treated.

• 대한기계학회논문집A
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• 제35권10호
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• pp.1171-1178
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• 2011

본 논문은 동적 시스템인 구동기의 강건설계를 수행한 결과를 제시한다. 구동기를 구성하는 부품들의 변량은 구동기의 성능에 변량을 유발한다. 따라서 부품들의 변량에 둔감한 구동기의 성능을 확보하기 위해 구동기에 대해서 강건설계를 수행하였다. 구동기를 구성하는 부품들을 전달함수로 표현하여 시뮬링크 모델로 구축하였으며, 시뮬링크 모델을 이용하여 설계 변수 조합에 따른 구동기의 응답을 얻었다. 또한 반응표면법을 적용하여 구동기의 응답을 설계 변수들의 2차 함수로 근사화하였다. 구동기응답을 출력으로 하는 근사화된 모델에 확률적 설계방법을 적용하여 강건한 구동기의 성능을 위한 최적 설계변수를 결정하고 기존 설계와 비교한 결과를 제시하였다.

• 한국기계가공학회지
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• 제7권3호
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• pp.3-11
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• 2008

Robust design pioneered by Dr. G. Taguchi has been applied to versatile engineering problems for improving quality. Since 1980s, the Taguchi method has been introduced to numerical optimization, complementing the deficiencies of deterministic optimization, which is often called the robust optimization. In this study, the robust optimization strategy is proposed by considering the robustness of objective and constraint functions. The statistics of responses in the functions are surrogated by kriging models. In addition, objective and/or constraint function is represented by the probability of success, thus facilitating robust optimization. The mathematical problem and the two-bar design problem are investigated to show the validity of the proposed method.

• 대한기계학회논문집A
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• 제28권9호
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• pp.1368-1383
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• 2004

Robust design has been developed with the expectation that an insensitive design can be realized. That is, a product designed by robust design should be insensitive to external noises or tolerances. Robust design can be classified into three methods: (1) The Taguchi method (2) robust optimization (3) robust design by the axiomatic approach. In this paper, each method is reviewed and investigated. Pros and cons fur each method are discussed and a future direction for development is proposed.

• 대한기계학회논문집A
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• 제35권10호
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• pp.1307-1313
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• 2011

전자제어식 차동제한 장치는 기계식에 비해서 능동제어가 가능하고 응답성이 좋아 기계식을 대체해 나가고 있다. STS 304 재질의 코일 하우징은 전자제어식 차동제한장치의 솔레노이드 어셈블리에서 가장 중요한 부품이다. 코일 하우징의 제조시 높은 형상 정밀도가 필수적이나, STS 304의 박판 사용과 가공변수의 변동으로 정밀 가공이 어렵다. 본 연구의 목적은 코일하우징의 가공조건에서 강건해를 구하여 평균과 변동을 최적화 하는 것이다. 코일하우징의 형상정밀도 평균과 표준편차를 최소화 하기 위한 주요 변수로 조의 척킹압력, 절삭속도, 이송속도의 평균과 표준편차가 고려됐다. 가공변수의 변동을 고려하여 평균과 표준편차를 모두 최소화 하는 최적의 조건을 선정하고자 반응표면모델 기반 2차 테일러 전개를 통한 강건 최적설계를 수행하였다.

• 대한기계학회논문집A
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• 제26권8호
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• pp.1719-1726
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• 2002

Design variables and design parameters are rarely deterministic in practice. Robust optimal design takes into consideration of the uncertainties in the design variables and parameters. Robust optimization methodology with probability constraints requires a lot of system analyses fer calculating failure probability of each constraint. By introducing an envelope function to reduce the number of constraints, efficiency of robust optimization techniques can be considerably improved. Through four illustrative examples, it is shown that the number of system analyses is greatly decreased while little differences in the optimum results are observed.

• 대한기계학회논문집A
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• 제25권9호
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• pp.1483-1492
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• 2001

A robust optimization procedure is applied to determine the design of the laminated composite plates with buckling constraints. In order to investigate the variation effect to the whole performance of a structure, both design variables and system parameters are assumed as random variables about their nominal values. The robust optimization method has advantages that the mean value and the variation of the performance function are controlled simultaneously and the second order sensitivity information is not required. Considering the information of uncertainty, robust optima for the buckling load of the laminated composite plates with cut-out is obtained. The robustness of the structures is compared to that of the deterministic optimization using scaling factors.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2010년 춘계학술대회논문집
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• pp.60-66
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• 2010

In the view of robust design optimization, RAE2822 airfoil was designed to achieve not only the maximum lift-to-drag ratio but also insensitivity of that. While the RAE2822 is flying at the cruise speed, Mach variation is considered as the operational uncertainty. In order to explore the design space, metamodels were introduced instead of consecutively computing the gradient. Also a metamodel was used to represent the sigma space. Using the metamodel, an optimum value was searched in the view of global optimization.