On the Improvement of Vibration Mitigation and Energy Harvesting Using Electromagnetic Vibration Absorber-Inerter: Exact H₂ Optimization

Electromagnetic resonant shunt tuned mass damper-inerter (ERS-TMDI) has recently been developed for dual-functional vibration suppression and energy harvesting. However, energy harvesting and vibration mitigation are conflicting objectives, thus rendering the multi-objectives optimization problem a very challenging task. In this paper, we aim at solving the design trade-off between these two objectives by proposing alternative configurations and finding the model with the best performance for both vibration suppression and energy harvesting. Three novel configurations are presented and are compared with the conventional ERS-TMDI. In the first two configurations, the primary structure and the absorber are only coupled through the spring. Both inerter and electromagnetic devices are connected to the ground in the first configuration, whereas only the inerter is connected to the ground in the second configuration. The third configuration is inspired by the recently developed three-element vibration-inerter (TEVAI), but in this case an electromagnetic device is sandwiched in between the primary structure and the absorber. Closed-form expressions are presented for optimum vibration mitigation and energy harvesting performances using H₂ criteria for both ground and force excitations. The obtained explicit expressions are validated using matlab optimization toolbox. Simulation examples reveal that the first configuration performs the best, whereas the second performs the worst in terms of both vibration mitigation and energy harvesting. It is also demonstrated that replacing the series RLC with a parallel circuit can improve or degrade the vibration mitigation performance, but it constantly enhances the energy harvesting performance in all four models.