Magnetically coupled flextensional transducer for impulsive energy harvesting

Impulsive energy is widespread in civil and industrial environment. Energy harvesting from ambient environment is considered as a promising way to replace the conventional batteries for powering wireless autonomous electronic devices. The combination of nonlinear bistable and flextensional mechanisms for impulsive energy harvesting has the advantages of high equivalent piezoelectric constant, high reliability and high sensitivity. The design consists of a cantilever beam with tip magnet and two magnetically coupled flextensional transducers (MCFTs). The coupled dynamical model is provided to describe the electromechanical transition. Experiments and simulations are carried out to evaluate the performances of the harvesters under different impulsive inputs by fingertip. Results verify that the coupled dynamical model can be used to characterize the harvester under impulsive excitation. The magnetically coupled flextensional impulsive energy harvester can work effectively under weak inputs and is reliable and durable under strong inputs.