Self-Latching Piezocomposite Actuator

摘要

A self-latching piezocomposite actuator includes a plurality of shape memory ceramic fibers. The actuator can be latched by applying an electrical field to the shape memory ceramic fibers. The actuator remains in a latched state/shape after the electrical field is no longer present. A reverse polarity electric field may be applied to reset the actuator to its unlatched state/shape. Applied electric fields may be utilized to provide a plurality of latch states between the latched and unlatched states of the actuator. The self-latching piezocomposite actuator can be used for active/adaptive airfoils having variable camber, trim tabs, active/deformable engine inlets, adaptive or adjustable vortex generators, active optical components such as mirrors that change shapes, and other morphing structures.

主权项

1. A method of controlling a self-latching piezocomposite actuator having a layer of shape memory ceramic fibers and first and second layers including conductive patterns disposed on opposite sides of the layer of shape memory ceramic fibers, the method comprising:
causing the shape memory ceramic fibers to have a first strain state by at least partially poling the shape memory ceramic fibers utilizing a first electric field that is induced by causing the voltage difference in the conductive patters of the first and second layers; followed by removing the voltage difference whereby the shape memory ceramic foam remain in the first strain state; followed by at least partially depoling the shape memory ceramic foam utilizing a second electric field having a polarity that is substantially opposite a polarity of the first electric field to thereby cause the shape memory ceramic fibers to have a second strain state that is not equal to the first strain state; at least one second layer disposed on the first layer, the second layer comprising a conductive material configured to conduct electric current to induce an electric field that causes the shape memory ceramic material to change from a first strain state to the second strain state and moves the second structural portion relative to the first structural portion, and wherein the shape memory ceramic material remains in the second strain state after the electric field is removed.