“…With the development of artificial intelligence, intelligent fault diagnosis techniques have also been developed, such as artificial neural networks (Gaing, 2004; Wu et al., 2007), support vector machine (Chunling et al., 2009; Kim and Lee, 2009), and linear discriminant analysis (Sakai et al., 2008). The application of these diagnosis techniques has been published in many works, including bearings (Yang and Tavner 2009; El-Thalji and Jantunen, 2015; Zhang et al., 2015), pumps (Du et al., 2013; Ding et al., 2015), engines (Macián et al., 2003), etc. However, most of the researches have put forward the fault diagnosis of the gear system, but most of them have the fault form of a single part – the multi-part coupling fault has not been put forward.…”