A piezoelectric–electromagnetic hybrid energy harvester inspired by flapping motion of the Diptera insect

Abstract

Low-frequency vibration is widespread in nature. Vibration energy harvesting is considered to be a reliable and sustainable method to achieve continuous power supply. It is a feasible method to design an energy harvesting system of the bio-inspired mechanical structure to improve the efficiency of energy harvesting. A hybrid energy harvester piezoelectric–electromagnetic that mimics the flapping wing motion of the Diptera insect. The biomimetic energy harvesting device consists of two piezoelectric cantilever beams structure with the mass block installed, which mimics the flapping movement mechanism of the Diptera insect. The intermediate part of this harvester inspired by the insect skeleton and muscle structure of the Diptera insect is composed of magnetic levitation coupled repulsion structure, which is easily affected by vibration and changes greatly, to realize electromagnetic energy harvesting. The ‘click’ mechanism of the Diptera insect is constructed by storing energy in springs to improve the performance of energy harvesting devices. The hybrid energy harvesting device realizes piezoelectric–electromagnetic energy harvesting with multiple energy outputs at one excitation input. A dynamic model of the proposed energy harvester is constructed based on the electromechanical coupling characteristics. The modal analysis and structure optimization of this device is realized by the finite element method (FEM). The FEM simulation and experimental results can verify that under the low-frequency excitation of 3 Hz, the maximum output power of the designed harvester reaches 12.33 mW in the low-frequency environment.

A piezoelectric-electromagnetic hybrid energy harvester for rotational motion driven by magnetic repulsion

“…As the mass blocks' augmentation alters the motion disk's gravity, there will be a corresponding rise in the displacement caused by the motion disk as gravity intensifies, alongside an increase in the magnetic flux's alteration. From the curve graph, the overall output performance becomes larger with the increase of mass blocks, and the number of mass blocks of 2 can be selected as the optimal variable, and the output voltage is 4.81 V. After measuring the optimal experimental variables through the experiment, in order to further test the power output of the EMH Dai et al [18] PZT and coil 10.07 mW -Tang et al [19] PZT and motor 8.31 mW Li et al [21] PZT and coil 6.598 mW 60.53 µW cm −3 Xing et al [22] RP150 and coil 2.98 mW -Fang et al [23] MFC and coil 12.33 mW -This work PZT and coil 53.45 mW 6.818 mW cm −3 under the optimal variables in the same way as the PEH measured the power, the output voltage and power results are shown in figure 11(d). The voltage at the EMH output increases with increasing load resistance, but the power shows a decreasing trend with increasing resistance.…”

“…The hybrid power can reach 2.98 mW. Fang et al [23] designed a piezoelectric-electromagnetic hybrid energy collection device based on the flapping wing movement mechanism of dipteran insects, and adopted magnetic levitation coupling repulsion to improve energy collection efficiency. Wang et al [24] proposed a non-contact rotating magnetic driven piezoelectricelectromagnetic HEH, and analyzed the effects of driving force, load resistance and electromechanical coupling strength on output performance.…”