激光自混和干涉（SMI）技术是一种利用光反馈原理进行的振动检测技术, 它具有结构简单, 非接触式测量振动信号的特点。为了解决齿轮箱故障诊断的问题, 提出了用激光自混合干涉技术提取信号,并通过小波变换对信号分析进行处理的方法。通过分析小波变换的各个分量以及最终经过小波变换去噪后的信号, 能够准确地识别出齿轮箱在运转时所存在的周期性振动故障信号, 实验得到的结果与理论值结果完全吻合。

The technology of self-mixing interference (SMI) is a kind of non-contact detection method which based on the principle of optical feedback and it has a very simple structure. In order to solve the problem of gearbox fault diagnosis, a method of self-mixing interference technology is proposed to process the fault vibration signal of gearbox based on wavelet transform analysis theory. The fault feature is extracted and analyzed. Through analyze the wavelet transform signal’s each component, it can accurately identify the existence of periodic vibration fault from the wavelet de-noised signal. The experimental result coincides with the theoretical result.