Feasibility study of shape control with zero applied voltage utilizing hysteresis in strain-electric field relationship of piezoelectric ceramics

摘要

To keep a shape of a smart structure controlled by piezoelectric actuators attached to it, electric voltage must be also continued to be applied. To reduce amount of electricity usage, a new control method is proposed. In this method strains of the piezoelectric actuators generated by pulses of voltages are kept with zero/less applied voltage by utilizing the hysteresis in strain versus electric field relationship effectively. In this paper to examine feasibility of this control method residual strains of piezoelectric ceramic plates are measured for combinations of amplitude and period of the applied pulse of voltages. Moreover, a cantilever beam on which a piezoelectric ceramic plate is bonded is made as a simple example of applications to the smart structures, and its deformation behavior after a pulse of voltage is observed. The result shows that the present control method is useful from viewpoint of applied energy, although the strain generated by the piezoelectric actuator is less than the conventional control method where the electric voltage is continued to be applied.