Eur. Phys. J. B (2018) 91: 254
https://doi.org/10.1140/epjb/e2018-90180-y

Regular Article

Multiple solutions of asymmetric potential bistable energy harvesters: numerical simulation and experimental validation

¹ Key Laboratory of Education Ministry for Modern Design and Rotor-Bearing System, School of Mechanical Engineering, Xi’an Jiaotong University, Xi’an 710049, P.R. China
² Materials and Structures Centre, Department of Mechanical Engineering, University of Bath, Bath BA27AY, UK
³ Faculty of Mechanical Engineering, Lublin University of Technology, Nadbystrzycka 36, Lublin 20-618, Poland
⁴ Department of Process Control, AGH University of Science and Technology, Mickiewicza 30, 30-059 Krakow, Poland

^a e-mail: caojy@mail.xjtu.edu.cn

Received: 17 March 2018
Received in final form: 19 July 2018
Published online: 15 October 2018

Abstract

In this paper, we investigate the multiple solutions of nonlinear asymmetric potential bistable energy harvesters (BEHs) under harmonic excitations. Basins of attraction under certain excitations explain the existence 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 frequencies 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 carried out, 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 are from the shallower potential well.