Vibration energy harvesting with a nonlinear structure

In the paper, beneficial nonlinearities incurred by an X-shape structure are explored for advantageous vibration energy harvesting performance. To this aim, a nonlinear structure beneficial for vibration energy harvesting is proposed, which is composed by X-shape supporting structures and a rigid body. By designing structure nonlinearities, which are determined by several key structure parameters, the power output peak of the harvesting system can be much improved and the effective frequency bandwidth for energy harvesting can be obviously increased, especially at the low frequency range. A coupling effect can be created among nonlinear stiffness and damping characteristics by constructing a 2-DOF vibration system, which has great influence on the energy harvesting performance. The proposed nonlinear energy harvesting systems can obviously outperform the corresponding linear systems in the whole frequency range and also demonstrate advantages compared with some other existing nonlinear energy harvesting systems in the literature. The results in this study provide a novel and practical method for the design of effective and efficient energy harvesting systems (especially in the low frequency range).