Low frequency vibration energy harvesting of bio-inspired multi-stable piezoelectric vibration system with an adjustable device

The bionic structure has unique nonlinear properties that can effectively broaden the energy harvesting band. Currently, this energy harvesting device lacks adjustability and adaptability to different environments. Inspired by the tracheas of the lungs, a lung trachea bio-inspired structure (LTBS) is proposed. The main structure of LTBS consists of springs, rods, gears and piezoelectric elements. The novelty of this model is the ability to adapt to different excitation environments by adjusting the steady-state model through rotating gears. The energy harvesting of the system is investigated using the RMS value of the induced voltage and the energy harvesting advantages and disadvantages characteristics are compared at various steady states. The coexisting basins of attraction are mapped and the best optimization scheme to improve its energy harvesting performance is obtained. An impulse perturbation was subsequently initiated to test the model. The test results show that the tri-stable to hexa-stable states exhibit excellent energy harvesting performance in low frequency and low amplitude excitation environments. The initiation of impulse perturbations significantly alters the energy harvesting efficiency and kinematic properties of the system and is limited by the basins of attraction of the system.