Acoustic signal separation of mechanical devices using ICA with band-pass filters

We propose a method of separating the acoustic signals of motors and the gears of mechanical devices by using independent component analysis (ICA) with band-pass filters. The frequency distribution of a recorded acoustic signal from the operating mechanical device can be divided into three fields, the low-frequency field, which corresponds to the frequency characteristics of the gear, the medium-frequency field, which is mixed with the frequency characteristics of the gear and the motor, and the high-frequency field, which corresponds to the frequency characteristics of the motor. Since only the medium-frequency components are a mixture of the acoustic signals of gears and motors, ICA with band-pass filters is expected to separate the acoustic signals of motors and gears more accurately than conventional ICA. The simulation and experimental results show that the proposed method can separate the acoustic signals of motors and gears of mechanical devices successfully.