Tri-stable stochastic resonance based on optimizing centrifugal distance for rotation-induced energy harvesting

This paper explores the application of tri-stable energy harvesting technology in tire rotation and proposes an innovative approach of optimizing the output of energy harvester by adjusting the centrifugal distance of the magnet at the free end of a cantilever beam. By leveraging the tunable linear stiffness in the electromechanical coupling equations of the rotating tri-stable state, this study derives an expression for the tunable stochastic resonance of the tri-stable system using Kramers escape rate. Further analysis of the frequency matching between the tunable stochastic resonance and the external rotational environment yields a formula for the optimal centrifugal distance. Both numerical and experimental results validate this theoretical analysis, demonstrating that at an optimal centrifugal distance of 7 cm, the effective bandwidth of the rotating tri-stable energy harvester remains stable between 30 and 60 rad/s. Due to precise matching between the stochastic resonance and the external rotation frequency, the RMS voltage can reach up to 2.24 V, with an average harvested power of 151.4 μW. This research significantly enhances the performance of the rotating tri-stable energy harvesting device, offering new insights for the application and development of energy harvesting technologies in smart vehicles.