Non-linear energy harvesting from coupled impacting beams

Abstract

Highlights• A coupled two beam system with non-linearity from impact and asymmetry is used to improve the energy harvested.• The influence of different system parameters, such as contact stiffness, clearance and asymmetry on the energy harvested was identified.• The power generated depends on the number of close modes within the bandwidth of excitation of the non-linear impact.• The asymmetry of the close mode shapes and the frequency spacing alters the power generated. AbstractEnergy harvesting has many potential applications for structures with broadband excitation, such as aircraft noise and low frequency vibrations from human motion.The advantage with a vibro-impacting system is the capability of converting low frequency response to high frequencies. A coupled beam system is base excited and the influence of different system parameters are studied. Exciting the system at a single resonant frequency highlights the influence of clearance and base excitation amplitude on the beam responses. The frequency sweep study shows the sensitivity of the power generated to the contact stiffness, damping and clearance between the beams. The power generated by the coupled system from the non-linear impact is sensitive to the thickness ratio of the beams and the clearance. The variation in thickness ratio alters the spacing of the natural frequencies of the system which causes modes to interact. This study shows that higher power is produced than the linear system, depending on the dissimilarity in the mode shapes of the interacting close modes.

Nonlinear Characterization of a Bistable Energy Harvester Dynamical System

“…The relative simplicity of this system motivates new analysis and layouts, for example, as seen in [30]. Although, as shown by Cottone et al [7] and, in more recent papers [20,21,41,42], nonlinear configurations, such as the bistable inverse pendulum depicted in Fig. 2, may present better power recovering performances, when compared to the linear counterparts.…”

Method for controlling vibration by exploiting piecewise-linear nonlinearity in energy harvesters

“…For instance, the array-harvester design can harvest the vibration energy over resonant frequencies of each linear system; however, the system set-up and the corresponding electronic configuration are complex, which makes the utilization very challenging [5]. Nonlinear energy harvesters [2,[18][19][20][21][22][23][24][25][26][27], which are commonly used in piezoelectric and electromagnetic generators, can broaden the effective frequency bandwidth by exploiting geometric and material nonlinearities; however, these nonlinear techniques are not as efficient as linear energy harvesters at resonance.…”

An Impact-Based Frequency Up-Converting Hybrid Vibration Energy Harvester for Low Frequency Application

“…Liu et al [17] replaced the driving element with a low-frequency piezoelectric beam, which not only generates electric power, but also introduce high frequency oscillation of the other piezoelectric generating beam. Vijayan et al [18] studied the dynamic characteristics of two coupled impacting piezoelectric beams. It was demonstrated that the power generated by the coupled system is sensitive to the thickness ratio of the beams and the clearance.…”