A frequency up-conversion rotational energy harvester with auxetic structures for high power output

Abstract

Rotational energy harvesters (REH) have been explored to substitute conventional batteries for small electronic sensors. However, there still exists a challenge for rotational energy harvesters to scavenge sufficient energy under low-rotational-frequency excitations. In this paper, we propose a plucking rotational energy harvester with auxetic structures, which utilizes the frequency up-conversion and auxetic structures to enhance the power output of the rotational energy harvesting under low-rotational-frequency excitations. Finite element simulation is performed to analyze the performanceof the proposed rotational energy harvester. The simulation results match well with the experimental ones. When the magnet distance is set to be 2.5 mm, the maximum power outputof the auxetic plucking rotational energy harvester (APREH) is found to be 1.43 mW at 1.1 Hz, which is increased by 686% compared with the conventional plain plucking rotational energy harvester (PPREH). In addition, compared with typical plucking rotational energy harvesters, the proposed auxetic plucking rotational energy harvester achieves the highest power output under low-rotational-frequency excitations, which validates the advantage of adopting auxetic structures in plucking rotational energy harvesters.

Out‐of‐Plane Dynamics of a Novel Auxetic Honeycomb with an Anti‐Trichiral Hierarchy

“…Auxetic metamaterials exhibit exceptional mechanical properties due to their counter-intuitive deformation characteristics, making them valuable across various fields including acoustic engineering, [14,32] seismic engineering, [33,34] medical devices, [1,35] smart sensors, [36,37] and protective engineering. [38,39] In recent years, researchers have increasingly explored tensileexpansive materials such as chiral structures, [40][41][42][43] reentrant structures, [27,44] and rotating polygonal structures, [45,46] focusing on their in-plane impact properties.…”