Toward Harvesting Vibration Energy from Multiple Directions by a Nonlinear Compressive-Mode Piezoelectric Transducer

We propose a new concept for harvesting vibration energy from multiple directions. Our approach effectively exploits the nonlinear vibration of a doubly clamped elastic rod, converting and amplifying excitations to compressive loads in piezoelectric materials. The proposed multidirectional compressive-mode piezoelectric energy harvester (MC-PEH) is capable of isotropically harnessing vibration energy from any angle in a plane. Meanwhile, the MC-PEH demonstrates a high-voltage output and a wide working bandwidth, along with the distinct softening nonlinear phenomena. Theoretical analysis and experimental testing are performed and exhibit good agreement over a range of excitation frequencies. This study enhances the practicability and adaptability of using energy harvesters in a complex environment.