Dynamic analysis of novel multi-link-spring mechanism for vibration isolation and energy harvesting

Abstract The study of the effective combination of vibration isolation and energy harvesting (VIEH) has become a popular topic at present. However, due to technical limitation, existed vibration isolator integrated energy harvesters have poor performance at low frequency. Therefore, this paper proposes a new multi-link-spring mechanism (MLSM), which can achieve quiz-zero-stiffness (QZS) and multi-stable characteristic by adjusting the parameters. Subsequently, the VIEH performance of MLSM under harmonic excitation and Gaussian white noise excitation are studied. And then, the influence of different parameters on the VIEH performance of the MLSM is analyzed. It was found that the MLSM can achieve any small stiffness in the equilibrium position and has well vibration isolation performance under low frequency or even ultra-low frequency. The frequency band can be widened by adjusting parameters to achieve higher energy harvesting power. Finally, the MLSM is compared with two special cases. The results show that the new MLSM is basically the same as the other two oscillators in terms of vibration isolation but has better energy harvesting performance under the multi-stable characteristic. The MLSM provided by this paper is expected to reduce the impact of external excitation on high-precision sensitive equipment in special sites such as subway and mine, and at the same time supply power to structural health monitoring device.