Optimal design and application of 3D printed energy harvesting devices for railway bridges

In this paper, the authors investigate energy harvesting on railway bridges. The tuning frequency for the optimal design of cantilever based 3D printed energy harvesters is studied. An analytical model to represent the electromechanical behaviour of the device is presented for the estimation of the energy harvested from train-induced bridge vibrations. A genetic algorithm constrained to geometry and structural integrity is used to solve the optimisation problem. Additive manufacturing by 3D printing of the substructure of the harvester is considered to maximise the design flexibility and energy performance. Optimal device prototypes with PAHT-CF15 substructure are designed for a real bridge in the Madrid-Sevilla High-Speed line. Finally, the performance of energy harvesting is evaluated from in situ experimental data measured by the authors. The results allow quantifying the energy harvested in a time window of three and a half hours and 19 train passages.