Experimental investigation of non-linear multi-stable electromagnetic-induction energy harvesting mechanism by magnetic levitation oscillation

The objective of this study is to present a multi-stable electromagnetic-induction energy harvesting (MEH) system by magnetic levitation oscillation. The MEH system has a non-linear restoring force and a multi-well restoring force potential, offering an improvement upon their linear counterparts by broadening its frequency response. This paper presents the mechanics of the electromagnetic-induction MEH system and describes the multi-stable mechanism by magnetic levitation oscillation. Experimental investigations reveal phenomena of dynamical bifurcation, escape from potential wells, high energy orbits, and chaotic oscillation. Two quad-stable and one tri-stable configurations are experimentally achieved and analyzed by means of phase portraits, Poincaré section, largest Lyapunov exponent, and bifurcation diagram. Algorithm of stroboscopic illustration of bifurcation diagram is elaborated. The results indicate that the electromagnetic-induction MEH system by magnetic levitation oscillation can be utilized to create a multi-well restoring force potential and increase the output current (i.e. electrical load capacity) of energy harvesters.