Bidirectional vibration energy harvesting and sensing system with biomimetic petal architecture

Self-powered wireless sensing systems face a fundamental challenge in effectively harvesting multidirectional low-frequency vibrations—a dominant feature in environmental mechanical energy spectra—while maintaining compact form factors. Conventional energy harvesters often exhibit limited adaptability to multidirectional excitations and poor efficiency at low frequencies. Inspired by the adaptive petal morphology of flowers, this work presents a flower-like bidirectional energy harvester (FLB-EH) incorporating quasi-zero stiffness (QZS) mechanisms for enhanced low-frequency vibration energy conversion. Through an integrated approach combining biomimetic design, nonlinear dynamics modeling, and systematic experimentation, this study deciphers the unique architecture of the FLB-EH and its role in bidirectional energy conversion, establishes a nonlinear electromechanical coupling model to quantify stiffness effects on power generation, and demonstrates a prototype achieving dual functionality as both a power source and self-powered vibration sensor. The synergistic integration of bioinspired petal morphology and QZS design, effectively resolving the two long-standing challenges in vibration energy harvesting systems: orientation adaptability and the difficulty of capturing low-frequency vibration energy.