An application of stochastic resonance for energy harvesting in a bistable vibrating system

摘要

The application of stochastic resonance to mechanical energy harvesting is currently of topical interest, and this paper concentrates on an analytical and experimental investigation in which stochastic resonance is deliberately exploited within a bistable mechanical system for optimised energy harvesting. The condition for the occurrence of stochastic resonance is defined conventionally by the Kramers rate, and the modelling of a theoretical nonlinear oscillator driven by a small periodic modulating excitation and a harvestable noise source, which, together satisfy this condition, is developed in the paper. A novel experiment is also discussed which validates this particular form of stochastic resonance, showing that the response can indeed be amplified when the frequency of the weak periodic modulating excitation fulfills the correct occurrence condition. The experimental results indicate that the available power generated under this condition of stochastic resonance is noticeably higher than the power that can be collected under other harvesting conditions.