This study investigates a slender hinged-roller nonlinear Euler-Bernoulli Beam subjected to a simple harmonic force applied in the axial direction. This nonlinear beam considered the stretching effect and also attached with a piezoelectric-patch (PZT-patch) to transfer nonlinear vibration energy into the electric power. Instead of applying the force on the beam’s transversal direction, the present work applies an axial force (an axial actuator) on the longitudinal direction to change the natural frequency of the beam (as shown in Fig.1) and hence control the beam vibration to achieve a maximum vibration energy harvesting.
The actuator's external force amplitude could also affect the stability of the entire system. Therefore, stability analysis will be studied to ensure the energy reliability of this vibration energy harvester (VEH) system. We employed the Method of Multiple Scales (MOMS) to analyse this nonlinear system. The Fixed-Point plots (steady state frequency response) were obtained and compared with the numerical results to verify if the internal resonance existed in this system.
The VEH system's stability information was obtained by the input-output amplitude plot. The proposed model can be used to adjust the amplitude or frequency of the actuator to control the beam's vibration amplitude and hence to have the maximum vibration energy transferring effect.
A simple experiment was performed (see Fig.2) to verify the analytical and numerical results. The output voltage of this VEH system from the present model agrees with experimental results very well. Our proposed model shows a wide application on energy engineering problems.
