Multiple solutions of asymmetric potential bistable energy harvesters: numerical simulation and experimental validation
In this paper we investigate the multiple solutions of nonlinear asymmetric potentialbistable energy harvesters (BEHs) under harmonic excitations. Basins of attraction under certainexcitations explain the existance of multiple solutions in the asymmetric potential BEHs and indicate that the asymmetric system has a higher probability to oscillate in the deeper potential well under low and moderate excitation levels. Thus, the appearance of asymmetric potentials in BEHs has a negative influence on the output performance. Average output powers under different excitation requencies and initial conditions illustrate that the asymmetric potential BEHs are more likely to achieve high-energy branch (HEB) with initial conditions in the shallower potential well, and the probability is influenced by the degree of asymmetry of the BEHs. Finally, experiments are carriedout, and results under constant and sweep frequency excitations demonstrate that the output performance will be actually improved for the asymmetric potential BEHs if the initial oscillations e shallower potential well