Dual-scale cascaded adaptive stochastic resonance for rotary machine health monitoring

Effective extraction of weak signals submerged in strong noise that are indicative of structural defects has remained a major challenge in fault diagnosis for rotary machines. Unlike traditional techniques that focus on noise filtering and reduction, stochastic resonance (SR) takes a noise-assisted approach to detecting weak signals. This paper presents a new adaptive method for weak signal detection, termed Dual-scale Cascaded Adaptive Stochastic Resonance (DuSCASR), which can quantify the frequency content of a weak signal without prior knowledge. Simulations and experiments have confirmed the effectiveness of the method in bearing fault diagnosis at the incipient stage, with high precision and robustness.