Emergence of non-reciprocity in metabeam exploiting piezoelectric sensing and actuation

A unique strategy by harnessing the concept of feedback control between the piezoelectric bimorph sub -cells which are acting as sensor and actuator is conceptualized in this paper. In the unit cell, voltages from the sensing bimorph are fed back to actuate another bimorph. The analytical formulation using transfer matrix method is developed to obtain the dispersion diagram. Development of the attenuation band gap and the characteristics of the mode shapes are explored for varying gain. Non-reciprocal behavior of the lattice is observed due to the directionality induced via electrical coupling arising from the dependence of the actuating bimorph on the sensing bimorph. The decaying waves in either direction give rise to an almost uninterrupted attenuation bandgap starting at very low free wave frequency. This phenomenon is observed even for reasonably lower value of the feedback gain. Hence, the proposed system could potentially be used for application in the field of vibration and acoustics.