Structural design of a speed-load synergistic stick-slip piezoelectric actuator with bi-directional backward motion suppression

Abstract The stick-slip piezoelectric actuator, employing the friction drive principle, will always experience backward motion, negatively affect the actuator’s accuracy and lead to increased wear, hence reducing its longevity. Furthermore, the coexistence of speed-load synergy and backward motion suppression at lower operating frequencies is still a technical challenge. This work presents a dual-layer stick-slip piezoelectric drive configuration. By supplying a designated piezoelectric signal to the upper and lower piezoelectric stacks to facilitate their cooperation, the lower lifting flexible hinge actuates the higher driving flexible hinge, resulting in the separation of the drive foot from the mover and the inhibition of rearward movement. This study delineates the structural composition and operational principles of the actuator, with enhanced performance substantiated using finite element analysis. A prototype of the actuator has been fabricated, and its output performance has been experimentally validated. The experimental results indicate that the actuator may substantially inhibit rearward motion. At a driving frequency of 375 Hz, with PES1 operating at 70 V and PES3 at 120 V, the actuator achieves a maximum speed of 9.75 mm s −1 , making it appropriate for low-frequency operational contexts. At an equivalent drive voltage, the maximum vertical load reaches 900 g when the drive frequency is 1 Hz. The displacement variation rate of the driver’s forward and reverse motion is 1.69%, indicating strong bidirectional consistency.