A dual-function compliant metastructure based on quasi-zero-stiffness for combined vibration isolation and vibration energy harvesting

This research presents a novel development in vibration control and energy harvesting by employing a quasi-zero-stiffness (QZS)-based dual function compliant metastructure. The integration of vibration isolation and energy harvesting into a single metastructure is one of the most effective methods to enhance energy efficiency and robustness under low-frequency excitations. In situations where low-frequency vibrations are predominant, the dual-purpose metastructure seeks to offer simultaneous vibration isolation and vibration energy collecting capabilities. The proposed design guarantees peak performance in low-frequency ranges by utilizing the high static low dynamic stiffness properties. In this work, four monolithic beams are used to form a metastructure and are fabricated using 3D printing. The polyvinylidene fluoride piezoelectric patches are used in series in the metastructure for collecting vibration energy and transforming low-frequency mechanical vibrations into electrical energy. The dynamic electromechanical equations are solved by using the harmonic balance method. The isolation region for QZS-based metastructure starts from much lower frequency ranges than the traditional linear isolators, and the transmissibility peak is also lowered. The experimental investigation reveals that an energy output of 368.64 mW is achieved at 4.5 Hz. Thus, the QZS-based metastructure designed for low-frequency areas offers a comprehensive and novel way to deal with the difficult problems related to vibration control and energy harvesting.