Stochastic resonance array for designing noise-boosted filter banks to enhance weak multi-harmonic fault characteristics of machinery

Abstract The role of potential-well width and potential-barrier height or potential-well depth in a triple-well potential on SR has not been investigated separately yet and the effect of a both uniform depth and different depth between left/right potential well and middle well in a triple-well potential on SR has not been explored yet. Meanwhile, SR is used to weak signal detection and early fault diagnosis, but it often processes a complex signal into a sine shaped one, resulting in the loss of multi-harmonic signature embedded in the raw signal. To avoid this, this paper investigates underdamped SR induced by a symmetric triple-well potential with a uniform depth. Then, a SR array based noise-boosted filter bank method is proposed to enhance weak multi-harmonic fault characteristics for early fault diagnosis of machinery. Theoretical results indicate that tristable SR induced by a symmetric triple-well potential with a uniform depth is superior to that induced by a symmetric triple-well potential with a different depth. Experimental results demonstrate that the proposed method is able to enhance weak multi-harmonic fault characteristics for early fault diagnosis of roller bearings.