Development of large-scale bistable motion system for energy harvesting by application of stochastic resonance

Stochastic resonance has become an important topic in the collection of environmental vibrational energy; however, realization of sufficiently large-scale motion for effective energy harvesting remains a difficult problem. Therefore, unlike the conventional vibrational systems that use cantilever beams, this study proposes a novel bistable motion system based on application of an elastic spring that diagonally supports a lumped mass block that can move freely along a straight rail. Using a combination of theoretical analysis, numerical simulation, and experimental verification, it is shown that stochastic resonance phenomena can be activated reliably using the proposed bistable motion system, and correspondingly large-scale bistable responses can be generated to realize effective amplitude enlargement after input signals are received. Additionally, it is demonstrated that large amplitude motion can be achieved with a highly robust performance because the rail-guided motion can suppress the effects of accidental impact from the outside. Furthermore, as an important design factor, the influence of periodic excitation signals on the large-scale bistable motion activity is carefully discussed and a solid foundation is laid for further practical energy harvesting applications.