Wide range tuning behavior of a new nonlinear energy harvester based on the beam–slider structure

Vibration energy harvesting from deflection of mechanical elements based on passive and active tuning mechanisms has attracted many researchers. In the present work, we propose a clamped–clamped beam–slider system combining with a tuning permanent magnet and an active controller to tune the system frequency proportional to the external excitation frequency to earn optimum harvested energy. The active controller consists a sliding mass, whose position is controlled by a motor through a cable. A set of nonlinear governing equations using extended Hamilton’s principle has been derived considering stretching effect of the cable and after applying Galerkin method using modified shape functions, the reduced equations have been integrated over time to specify the tuning response of the harvester for both passive and active cases. The results show a significant enhancement of the bandwidth of the harvester for different cases. The self-tuning behavior of the system confirms our analysis with the previous experiments. To verify the obtained analytical operating frequency range, we conduct a FE simulation in the COMSOL multiphysics environment. The provided magnets by changing the equivalent stiffness of the system give the ability to operate the harvester over a wider range of excitation frequencies. The added controller tracks the slider position and concerning with favorable resonant slider position adjusts the system to capture the higher energy orbits. From the perspective of mathematical modeling, the presented modeling connects the problem of beam-fixed mass and beam–slider due to the added cable.