Analysis and Design of an X-Structured Nonlinear Energy Harvesting System: A Volterra Series-Based Frequency Domain Method

In recent years, in order to exploit beneficial nonlinearities, an X-shaped supporting structure with helpful nonlinear stiffness and damping characteristics has been developed and deliberately introduced to improve the energy harvesting performances. In this paper, the Volterra series-based frequency domain method is utilized to achieve a systematic analysis and design of the present X-structured nonlinear system. The generalized frequency response functions (GFRFs) and the output frequency response function (OFRF) of the system are theoretically derived using the recursive algorithm. Importantly, analytical relationships between the power generation function (PGF) of the harvesting system and the structural parameters of the X-structure would be derived, to show how the power generation is affected by the structural parameters of the system. The results indicate that, the present study could provide an effective and efficient way to characterize the nonlinear effects on the proposed energy harvesting system.