“…The use of the combined Lagrangian makes the derivation of the fully dynamic electromagnetic current-controlled models (18) and (20) possible. Furthermore, a physical interpretation can be given to the coupling components present in the Lagrangian which are not present in the total energies (19) and (21), through the existence of so-called traditors [20]. In the case of the novel current actuated piezoelectric composites, we are dealing with a gyrator type traditor with gyrating constant γ present in the combined Lagrangian L k and also in ( 16) and (17), used for deriving the mathematical models.…”