A New Mechanical Band Pass Filter Design For Energy Harvesting

This work presents an analytical methodology for development of a mechanical band pass filter for energy scavenging. The model is based on Adomian decomposition method to derive the dynamic response of the non-uniform smart structure with strain rate damping to external environmental excitations and efficiently harvest the subsequent vibrational energy. The steady state response of the nonlinearly tapered cantilever beam subjected to a harmonic base motion is obtained and electromechanical outputs in open circuit condition are analytically derived. In other to design a band pass filter, an array of cantilever beams with nonlinear geometry and surface bonded piezoelectric layers are considered. Therefore, the filter can choose one harvester to resonate at one particular ambient vibration frequency and reach the maximum electromechanical output. Compared with uniform beam design, it is also demonstrated that the proposed non-uniform configuration can generate higher electrical output over a wide frequency range.