【作者】 时丽娜；

【导师】 朱利民；

【作者基本信息】 上海交通大学 ， 机械电子工程， 2007， 硕士

【摘要】 对机械设备的关键部件进行状态监测与故障诊断是现代化工业生产的重要研究问题。本论文研究了面向故障诊断的传感器布局规划和微弱信号检测方法,其中前者以夹具故障诊断为例,后者以滚动轴承故障诊断为例。全文主要研究工作如下:1.鉴于制造过程中,许多诊断溯源问题,如夹具故障诊断、几何误差溯源和梁结构装配变形溯源,都可以用统一的线性故障模型表示,并可归结为统一的线性参数估计问题,本文主要以夹具故障为例,在最小二乘参数估计的基础上,提出了一种基于模型的故障诊断方法。这种方法不仅适用于多个故障的诊断,而且适用于均值故障和方差故障都存在的情况。对每一个定位元位置误差变量,首先进行方差检验,当检验无方差故障时,再进行均值检验,这样就既避免了对同一个定位元故障的重复检验,又避免了因只检验其中一种故障而导致得出错误结论。该方法能够准确全面地检验出系统故障的个数、位置及类型。2.针对故障诊断的目的,从所定义的两个检验统计量出发提出了一更多还原

【Abstract】 Sensing and signal processing are the key techniques for condition monitoring and fault diagnosis. In this thesis, several approaches for sensor layout planning and weak signal detection are addressed with applications to machine and manufacturing process fault diagnosis. The main contents of the thesis are summarized as follows.1. Several diagnostic problems arising from manufacturing processes, i.e., diagnosis of fixture fault, diagnosis of geometric imperfection and diagnosis of beam structure deformation, are modeled as a unified linear parameter estimation problem. Case of diagnosis of fixture fault is mainly discussed in this paper. A method of model-based fault diagnosis, based on the least squares estimation method is developed. This method not only can detect and classify multiple faults, but also can be applied to the situation of mean fault and variance fault coexisting. It starts with the variance detection, if no variance fault is detected in the i thfault, and then continues to do the mean fault detection. Thus, on the one hand, the repeating detection of the same i thfault is avoided; on the other hand, the possibility of deriving the wrong diagnostic conclusion is avoided if only detect one of the two types of faults while ignore the other one existing.更多还原