【作者】 吴飞跃；

【导师】 张国军；

【作者基本信息】 华中科技大学 ， 工业工程， 2007， 硕士

【摘要】 如何有效地识别和分析产品故障,并在此基础上进行产品可靠度预测,对于企业预防产品故障和制定产品维修计划,具有十分重要的意义。随着产品的可靠性不断提高,能够获得的产品的故障数据变得十分有限,因而难以通过大量故障数据的分析进行故障识别。在此背景下,本文研究了基于统计学习理论的产品故障分析及可靠度预测技术,并开发了原型系统进行验证。在研究故障分析与可靠度预测系统工作原理的基础上,建立了该系统的体系结构。针对机械产品的故障大多属于小子样问题,利用统计学习理论和支持向量机进行故障模式识别,并将支持向量机的二分类方法和多分类方法分别用于汽车发动机单一故障识别和多故障识别之中。该方法较为有效的避免以往机器学习方法在小子样条件下表现不佳的情形。在利用支持向量机有效的识别产品故障模式之后,将FMEA和FTA相结合起来进行故障分析,该方法不但能够弥补FMEA或FTA分析技术各自的不足,而且能够实现从FMEA表格到FTA故障树的自动生成,更加有效的找出具体故障原因。研究了基于统计学习理论的产品性能退化趋势的线性回归方法,实现了利用退化数据进行退化方式相关条件下的产品可靠度预测,并以发动机机壳为对象进行了实例研究。结果表明,该方法能比较准确地判断退化型故障产品的可靠度是否低于用户允许的限度。开发了故障分析和可靠度预测原型系统,对上述理论和技术进行了验证。更多还原

【Abstract】 Reliability prediction based on effective identification and analysis of failure is very meaningful to the enterprises in failure prevention and maintains scheduling. With the improvement of product reliability, it is difficult to acquire enough data used to identify failure based on data analysis. Technologies of failure analysis and reliability prediction based on statistical learning theory are presented. A prototype system is developed for validation.The framework structure of failure analysis and reliability prediction system is built based on the analysis of work principle.The statistical learning theory and support vector machines are introduced to identify the mechanical product failure, which is a typical small-sample problem. The binary classification method and the multi-classification method are applied in the classification of single failure and multi-failure mode in automobile engine. The result shows that the statistical learning theory and support vector machines can improve the accuracy compared to the conventional machine learning methods.The FTA and FMEA are integrated to analyze the failure modes identified by the support vector machines. The new method can lessen the limitation of FMEA or FTA. Meanwhile, the Fault Tree (FT) can be generated automatically by the FMEA tabulation, which is help to effectively identify the specific cause of failure.The linear regression method of degradation prediction based on the statistical learning theory is presented. The degradation data is used to predict the reliability of product with related degradation modes. A case study is given taking the shell of the automobile engine as an example. The result shows that this method can accurately judge whether the reliability of the product is lower than the customer’s expectation.A failure analysis and reliability prediction system is developed to validate the theory and methods mentioned above.更多还原