Mobile device-based bearing diagnostics with varying speeds

The mobile device has become an essential electronic device in everyday life. With embedded sensors, wireless connections, and high-performance processors, the mobile device has great potential to become a convenient tool for machinery diagnostics. Without any additional cost, it is especially suitable for machinery diagnostics with low budgets. The study investigates the feasibility of bearing fault diagnosis using mobile device. Quasi-tachometer signal analysis is proposed to restore transient phase signal of bearing shaft. And it is further utilized to perform order tracking of the fault-induced impulses extracted by Kurtogram. The bearing fault is featured with the harmonic peaks at bearing characteristic order in the envelope order spectrum. A case study of smartphone for bearing diagnosis is used to illustrate the procedures and performance of the scheme. The main contribution of the paper is to provide the analysis tool for bearing diagnosis under varying speeds condition via commonly used mobile devices.