• Title/Summary/Keyword: Reliability Design

Search Result 5,455, Processing Time 0.04 seconds

Reliability Evaluation of Torque Generator (토크 발생기의 신뢰성 향상)

  • Jung, D.S.;Lee, Y.B.;Park, J.W.
    • Journal of Power System Engineering
    • /
    • v.16 no.6
    • /
    • pp.59-65
    • /
    • 2012
  • Torque Generator is a product which has function to transform hydraulic energy to mechanical energy of torque and rotating speed, and be used for direction change device of agricultural machines. This study proposes failure analysis and test analysis on torque generator and introduces a process that reliability of a product is enhanced by design improvement. And also it presents improvements of maximum output torque by modifying design and surface treatment. Lastly it verifies reliability improvement by analyzing test results of before and after life test.

Reliability analysis of latticed steel towers against wind induced displacement

  • Khan, M.A.;Siddiqui, N.A.;Abbas, H.
    • Steel and Composite Structures
    • /
    • v.4 no.1
    • /
    • pp.9-21
    • /
    • 2004
  • The present study aims at the reliability analysis of steel towers against the limit state of deflection. For this purpose tip deflection of the tower has been obtained after carrying out the dynamic analysis of the tower using modal method. This tip deflection is employed for subsequent reliability analysis. A limit state function based on serviceability criterion of deflection is derived in terms of random variables. A complete procedure of reliability computation is then presented. To study the influence of various random variables on tower reliability, sensitivity analysis has been carried out. Design points, important for probabilistic design of towers, are also located on the failure surface. Some parametric studies have also been included to obtain the results of academic and field interest.

다목적실용위성 2호기 신뢰성 및 FMECA

  • Lee, Chang-Ho
    • Aerospace Engineering and Technology
    • /
    • v.2 no.1
    • /
    • pp.44-53
    • /
    • 2003
  • The purpose of reliability prediction is to estimate the basic reliability and basic reliability and mission reliability of system and to make a determination of whether these reliability requirements can be achieved with the proposed design. Also, potential design weakness can be identified through the FMECA process. This technical memo summarizes the KOMPSAT-2 reliability and FMECA analysis results.

  • PDF

Reliability Estimation Using Kriging Metamodel (크리깅 메타모델을 이용한 신뢰도 계산)

  • Cho Tae-Min;Ju Byeong-Hyeon;Jung Do-Hyun;Lee Byung-Chai
    • Transactions of the Korean Society of Mechanical Engineers A
    • /
    • v.30 no.8 s.251
    • /
    • pp.941-948
    • /
    • 2006
  • In this study, the new method for reliability estimation is proposed using kriging metamodel. Kriging metamodel can be determined by appropriate sampling range and sampling numbers because there are no random errors in the Design and Analysis of Computer Experiments(DACE) model. The first kriging metamodel is made based on widely ranged sampling points. The Advanced First Order Reliability Method(AFORM) is applied to the first kriging metamodel to estimate the reliability approximately. Then, the second kriging metamodel is constructed using additional sampling points with updated sampling range. The Monte-Carlo Simulation(MCS) is applied to the second kriging metamodel to evaluate the reliability. The proposed method is applied to numerical examples and the results are almost equal to the reference reliability.

Reliability-Based Topology Optimization Using Single-Loop Single-Vector Approach (단일루프 단일벡터 방법을 이용한 신뢰성기반 위상최적설계)

  • Bang Seung-Hyun;Min Seung-Jae
    • Transactions of the Korean Society of Mechanical Engineers A
    • /
    • v.30 no.8 s.251
    • /
    • pp.889-896
    • /
    • 2006
  • The concept of reliability has been applied to the topology optimization based on a reliability index approach or a performance measure approach. Since these approaches, called double-loop single vector approach, require the nested optimization problem to obtain the most probable point in the probabilistic design domain, the time for the entire process makes the practical use infeasible. In this work, new reliability-based topology optimization method is proposed by utilizing single-loop single-vector approach, which approximates searching the most probable point analytically, to reduce the time cost. The results of design examples show that the proposed method provides efficiency curtailing the time for the optimization process and accuracy satisfying the specified reliability.

Quality Function Deployment of Core Unit for Reliability Evaluation of Machine Tools (공작기계 핵심부품의 QFD 기술)

  • 송준엽;이승우;강재훈;강재훈;황주호;이현용;박화영
    • Proceedings of the Korean Society of Precision Engineering Conference
    • /
    • 2001.04a
    • /
    • pp.59-62
    • /
    • 2001
  • Reliability engineering is regarded as the major and important roll for all industry. And advanced manufacturing systems with high speed and intelligent have been developing for the betterment of machining ability. In this study, we have systemized evaluation of reliability for machinery system. We proposed the reliability assessment and design review method using analyzing critical units of high speed and intelligent machine system. In addition, we have not only designed and developed test bed system for acquiring reliability data, but also apply QFD technique for satisfying quality function which is provided in design phase. From this study, we will expect to guide and introduce the reliability engineering in developing and processing phase of high quality product.

  • PDF

Reliability Evaluation of Multi-Stage Gear Drive (다단 기어장치의 신뢰성 평가에 관한 연구)

  • Chong Tae-Hyong;Kim Young-Ju;Park Seung-Hyun
    • Transactions of the Korean Society of Machine Tool Engineers
    • /
    • v.15 no.2
    • /
    • pp.16-23
    • /
    • 2006
  • Recently the design of multi-stage gear drive is being highly concerned. Until now, since the researches of gear drive are focused on the design for satisfying safety factor, the reliability evaluation of multi-stage gear drive is not included. In this paper, the life and reliability models of multi-stage gear drive are proposed using methods of probability and statistics. The life and reliability of the multi-stage gear drive have been evaluated, which is based on the life and reliability of each stage gear drive. The pinion and gear lives of each stage are calculated using the Lundberg-Palmgren theory and the Weibull failure distribution. These lives are combined using methods of probability and statistics to produce a life and reliability model of multi-stage gear drive.

Practical Reliability Growth Management for RAM Growth Monitoring (RAM 성장모니터링을 위한 실용적인 신뢰성 성장관리)

  • Jung Won
    • Proceedings of the KSR Conference
    • /
    • 2005.11a
    • /
    • pp.258-263
    • /
    • 2005
  • The purpose of this research is to present a practical method for efficiently monitoring a reliability growth process using AMSAA(Army Materiel Systems Analysis Activity) reliability growth model. The presented method is viable for identifying failure modes, incorporating design changes and monitoring reliability progress on an on-going basis during the early stages of a product development program. According to the Application Guide for EN 50126(RAM part for Rolling Stock), reliability growth monitoring is essential part of the main tasks of design phase in RAM growth monitoring. Implementation of reliability growth management program will provide very useful information on concept selection, product/process reliability, and cost effectiveness without too much time, money and engineering effort being spent on the development of failure suspect parts.

  • PDF

Reliability-Based Topology Optimization for Different Engineering Applications

  • Kharmanda, G.;Lambert, S.;Kourdi, N.;Daboul, A.;Elhami, A.
    • International Journal of CAD/CAM
    • /
    • v.7 no.1
    • /
    • pp.61-69
    • /
    • 2007
  • The objective of this work is to integrate reliability analysis into topology optimization problems. We introduce the reliability constraint in the topology optimization formulation, and the new model is called Reliability-Based Topology Optimization (RBTO). The application of the RBTO model gives a different topology relative to the classical topology optimization that should be deterministic. When comparing the structures resulting from the deterministic topology optimization and from the RBTO model, the RBTO model yields structures that are more reliable than the deterministic ones (for the same weight). Several applications show the importance of this integration.

An improved response surface method for reliability analysis of structures

  • Basaga, Hasan Basri;Bayraktar, Alemdar;Kaymaz, Irfan
    • Structural Engineering and Mechanics
    • /
    • v.42 no.2
    • /
    • pp.175-189
    • /
    • 2012
  • This paper presents an algorithm for structural reliability with the response surface method. For this aim, an approach with three stages is proposed named as improved response surface method. In the algorithm, firstly, a quadratic approximate function is formed and design point is determined with First Order Reliability Method. Secondly, a point close to the exact limit state function is searched using the design point. Lastly, vector projected method is used to generate the sample points and Second Order Reliability Method is performed to obtain reliability index and probability of failure. Five numerical examples are selected to illustrate the proposed algorithm. The limit state functions of three examples (cantilever beam, highly nonlinear limit state function and dynamic response of an oscillator) are defined explicitly and the others (frame and truss structures) are defined implicitly. ANSYS finite element program is utilized to obtain the response of the structures which are needed in the reliability analysis of implicit limit state functions. The results (reliability index, probability of failure and limit state function evaluations) obtained from the improved response surface are compared with those of Monte Carlo Simulation, First Order Reliability Method, Second Order Reliability Method and Classical Response Surface Method. According to the results, proposed algorithm gives better results for both reliability index and limit state function evaluations.