Modeling and experimental validation of new two degree-of-freedom piezoelectric actuators

This study presents innovative two-degree-of-freedom piezoelectric actuators, which apply piezoelectric buzzers to play as a driving source. Under piezoelectric force and dry friction, the piezoelectric actuators not only can move in the Z-axis direction, but also rotate along the Y-axis. The Z-axis displacement can reach 62 mm and the rotation angle along the Y-axis can reach 270°. Compared with the literature, this innovative piezoelectric actuator design easily and rapidly achieves one degree-of-freedom translation and one degree-of-freedom rotation. Equations of motion are derived based on piezoelectric properties and Newton’s law. Two types of actuators are created in this study. In the first type, centers of two piezoelectric buzzers are attached to an arm while in the other type each rim of two piezoelectric buzzers is attached to the arm. Experimental results are compared with theoretical results. According to experimental results, the present actuator can accomplish the translational velocity of 21 mm/s, angular velocity of 3.72 rad/s, and 2.32 mN in force. This study presents a piezoelectric actuator capable of both translation and rotation, which is rare in the literature.