• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2011년도 정기 학술대회
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• pp.345-348
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• 2011

구조요소의 설계에서 유한요소해석은 매우 효과적인 방법이다. 이 방법은 시험 수행에 드는 시간과 비용을 줄여준다. 그러나 공정 과정과 환경에 의하여 생기는 입력 물성치들의 변화 때문에 우리는 유한요소해석의 결과를 전적으로 믿어서는 안 된다. 따라서 유한요소해석의 신뢰성을 증명하는 것은 매우 중요하다. 본 연구에서는 현장에 축적된 피로 수명 시험 데이터를 바탕으로 유한요소해석을 이용하여 피로수명 파라미터를 역 추정 하는 연구를 수행하였다. 베이지안 접근법을 이용하여 불확실성 피로 수명 파라미터의 사후분포를 구하였고, 마코프체인몬테카를로(Markov Chain Monte Carlo) 기법을 이용하여 역 추정된 파라미터의 샘플 데이터를 생성하였다. 얻어진 샘플 데이터를 기반으로 새로운 형상의 스프링에 대한 피로 수명을 예측한다. 신뢰성 기반 형상 최적화(RBDO)는 서스펜션 코일 스프링의 요구수명을 만족시키기 위하여 수행된다. 또한 크리깅 근사 모델은 유한요소해석의 연산 량 감소를 위해 이용한다.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2002년도 추계학술대회논문집
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• pp.771-776
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• 2002

Optimal shape of the NFR suspension is studied and developed to improve the dynamic performance and reduce the vibration of the suspension system including a optical head slider. Since accurate position control and stability of the slider motion are highly required in NFR due to the narrower track width and the heavier slider than HDD slider with the low flying height, the dynamic characteristics of the suspension are very important to the mechanical performance of the system. The first natural frequencies in flexural and lateral motion of the suspension are critical factors affecting the dynamics and stability of the flying head, so that the dynamic parameters should be designed properly to avoid an excessive vibration or a crash of the slider on the disk. This paper optimizes the shape of the suspension based on homogenization method in NASTRAN and develops a new suspension shape for NFR system. The suspension is tested on experiment to verify the improvement of the dynamic characteristics.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2002년도 추계학술대회논문집
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• pp.570-575
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• 2002

Servo performance of a disk drive is greatly affected by the mechanical resonance frequencies of the head gimbal assembly (HSA). It is important factor to allow broader bandwidths for servo system in improving overall drive performance. In this paper, an optimal design for ODD suspension is attempted to increase resonance frequencies in tracking direction. Initial model was designed and the design parameter was defined to the model. The mode frequency variation for the change of design parameter was observed by modal analysis using the finite element method(FEM). The sensitivity matrix was calculated from the observed data and so through sensitivity analysis, an optimized ODD suspension was designed to have the higher resonant frequency than the initial model.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2001년도 춘계학술대회 논문집
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• pp.155-160
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• 2001

The road simulator system can simulate the longitudinal, lateral, and vertical movement changed by road conditions and vehicle dynamic characteristics while driving. This system provides the durability evaluation of vehicle suspensions. The system consists of hydraulic actuators, link mechanism, and servo controller. The hydraulic actuators are specially manufactured using low friction seals to endure high speed movement. The link mechanism is designed in order to minimize the dynamic effect during motion and remove the interference between 3axes actuators. The servo controller is composed of sensors, sensor amplifiers - displacement transducers and load cells, and an industrial PC with DSP board which calculates the control algorithm to control hydraulic actuators. The test results are included to evaluate the performance of this simulator comparing vehicle driving test.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2002년도 추계학술대회논문초록집
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• pp.359.1-359
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• 2002

Servo performance of a disk drive is greatly affected by the mechanical resonance frequencies of the head gimbal assembly(HGA). It is important (actor to allow broader bandwidth for servo system in improving overall drive performance. In this paper, an optimal design for ODD suspension is attempted to increase resonance frequencies. It was decided that the first resonant frequency in tracking direction was higher than 5㎑. (omitted)

• 정보저장시스템학회:학술대회논문집
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• 정보저장시스템학회 2005년도 추계학술대회 논문집
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• pp.163-170
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• 2005

In this work, we propose a new type of HDD Load/unload (L/UL) suspension featuring shape memory alloy (SMA). The mechanical and thermal properties of the SMA film with respect to the material phase states are experimentally estimated and the SMA film is carefully integrated to the suspension. In order to obtain the desirable dynamic characteristics of the suspension during L/UL process, the design parameters of the SMA film such as geometric properties are determined by considering the vibration modes of the suspension related to the L/UL performance. After analyzing the modal characteristics of the proposed suspension, L/UL performance is evaluated through L/UL simulation by observing the vibration motion and minimum flying height of the slider during L/UL process.

• 한국자동차공학회논문집
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• 제6권6호
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• pp.31-39
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• 1998

The role of bushing elements linked between suspension parts is to enhance ride quality and handling stability by the spring and damping effect from the elastic deformation. In this paper, a theoretical derivation and computer implementation off a bushing element are proposed. Three different vehicle models are generated to test the developed bushing module. The developed bushing module is implemented as a bushing module in the vehicle dynamic analysis program AUTODYN7.

• 정보저장시스템학회논문집
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• 제2권1호
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• pp.71-78
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• 2006

In this work, we propose a new type of HDD Load/Unload(L/UL) suspension featuring shape memory alloy(SMA). The mechanical and thermal properties of the SMA film with respect to the material phase states are experimentally estimated and the SMA film is carefully integrated to the suspension. In order to obtain the desirable dynamic characteristics of the suspension during L/UL process, the design parameters of the SMA film such as geometric properties are determined by considering the vibration modes of the suspension related to the L/UL performance. After analyzing the modal characteristics of the proposed suspension, L/UL performance is evaluated through L/UL simulation by observing the vibration motion and minimum flying height of the slider during L/UL process.

• 한국전자통신학회논문지
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• 제17권6호
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• pp.1243-1248
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• 2022

비정형 환경인 건설 현장에서 안정적으로 운영할 수 있는 이동 플랫폼은 스마트 건설기술 개발에 있어 중요한 문제이다. 본 논문에서는 건설 현장 지형정보 수집 지원을 위해 비정형 환경에서도 강인하게 주행할 수 있는 이동 로봇 플랫폼을 소개한다. 제안한 이동 플랫폼은 종경사 뿐만이 아닌 횡경사에도 대처할 수 있도록 설계하였으며 시뮬레이션 실험을 통해 제안한 플랫폼의 단차 극복성능을 분석하였다.

• 한국정밀공학회지
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• 제14권2호
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• pp.13-22
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• 1997

Strapdown inertial navigation system(SDINS) is a navigational instruments necessary to guide and con- trol a free vehicle. In this study, an error analysis of mechanical parts is carried out for manufacturing a dynamically tuned gyroscope. The errors usually come from the tolerance in machining and assembly. In the error analysis, a criterion to be considered during designing and manufacturing is proposed by quanti- tatively analyzing the effect of DTG performance by tolerances. The theory of dynamic balancing is deduced and unbalance is reduced through experiment.