Restraining the Backward Motion of a Piezoelectric Stick-Slip Actuator With a Passive Damping Foot

The backward motion is an intrinsic feature of the conventional piezoelectric stick-slip actuator (PSSA), limiting the output speed and applications. Various methods have been proposed for restraining the backward motion. Each method has its pros and cons for the practical application of driving a precision motion stage. A novel method for restraining the backward motion is proposed in this article, in which a passive damping foot is utilized to hold the runner when the active driving foot slips on the runner. An actuator is developed based on this mechanism. The structural dimensions of the actuator are determined with an analytic model and a finite element model. A prototype of the proposed actuator is fabricated and tested by experiments. The experiments validate the operating principle of the actuator for restraining the backward motion, which is eliminated (the backward ratio is less than 1%) when the passive damping foot has an appropriate clamping force. The proposed method is very valuable for designing a PSSA with no backward motion, and it can broaden the applications for precision manipulations.