Study On Controlling Stochastic Resonance Of Coupled Bistable System And Its Application

The stochastic resonance phenomenon only can arise under thecooperative effect of noise, weak periodic signal and nonlinear system. Whilein the circumstance of practical application, the noise intensity and frequencyare given and the parameters of nonlinear system cannot changed directly.Thereby, the stochastic resonance cannot be controlled by adjusting potentialheight and thresholds. The paper takes the coupled bistable system which iscomposed of controlled system and control system by means of nonlinearcoupling as research objects, and its characteristic are analyzed.Firstly, based on the model of coupled bistable system, the feedbackcontrol framework of stochastic resonance was established. The mechanismof the occurrence of stochastic resonance was analyzed, and the influence onstochastic resonance of the coupled coefficient, control system’s parameterand additional control signal’s parameter were elaborated. The controlmethod of stochastic resonance based on adjusting the coupled coefficientand control system’s parameter alone with dual-resonance was proposed.Secondly, the controlled instrument of coupled bistable system wasdeveloped, and its hardware part and software part were designed and tested.The simulation test of coupled bistable system circuit was competed by usingMultisim software that manifest the circuit can generate stochastic resonancewith effect. The software part which was designed by taking advantage ofLabVIEW software can provide a convenient way to study coupled bistablesystem stochastic resonance, and it can detect weak signal effectively.Finally, the above-mentioned theoretical control methods of stochasticresonance and the controlled instrument of coupled bistable system were putinto practice in engineering. Put the bearing inner crack fault and wearabrasion signals as well as vortex shedding signals into detection respectively,and the detection results show that the method can detect the fault signa l accurately and effectively. The controlled instrument of coupled bistablesystem is convenient and effectively to detect weak signal, and it shows avery promising applicable future.