Flexural modes coupling in cantilever-type piezoelectric energy harvesters

The ability to harness the waste mechanical energy and convert it into useful electrical power has made kinetic harvesters a promising candidate provide an everlasting source for wireless autonomous devices. Nonlinearities, whether introduced deliberately sake of bandwidth broadening or present intrinsically, can highly influence dynamic response output behavior these type scavengers. This paper aims investigate effect nonlinearity on multi-mode vibrational harvester composed cantilevered piezoelectric composite beam with attached mass finite dimensions. To that end, first all 3-DoF lumped parameter coupled electromechanical model device is developed through comprehensive mathematical approach its mode shapes natural frequencies are calculated. perturbation method multiple scales then applied obtain steady state solutions extracted order-reduced governing equations system. Results indicate cubic exhibits simple Duffing-type resonance as excitation frequency falls in vicinity each frequency. That occurs while U-shaped vibration modes would be occurrence internal resonance. In this latter case, both flexural stimulated by single contribute generation leading enhancement total which major advantage proposed design compared other existing harvesters. curves found four branches include Hopf bifurcations instability regions. verify results obtained from analytical approach, they numerical solution where good agreement observed between them.