Bifurcation analysis and nonlinear dynamics of a rolling magnet multistable electromagnetic energy harvester

The objective of this study is to provide a rolling magnet multistable electromagnetic-induction energy harvester (RM-MEH) for scavenging energy from a wide frequency range. The RM-MEH designed based on a magnetic levitation rolling magnet possesses the merit of small damping. By clarifying the mechanics of the RM-MEH, the static bifurcation behavior is investigated and results demonstrate that monostable, bistable, and tristable configurations with different types of potentials can be obtained with proper parameters. Numerical simulations under sweep frequency excitation indicate that the monostable, bistable, and tristable configurations with proper potential functions achieve large-amplitude oscillation in a wide frequency range. Under constant frequency excitation, the nonlinear dynamics are analyzed utilizing the bifurcation diagram, phase orbit, and Poincaré map, and the multiple vibrational patterns are verified. Finally, the vibration isolation characteristics of the system are briefly discussed considering the electromagnetic force of the RM-MEH. In summary, the demonstration of the novel RM-MEH expands the approach to achieving multistable oscillation and provides a new way of thinking for designing nonlinear energy harvesters.