A novel low-frequency driving and high-speed motion stick-slip piezoelectric actuator based on two-stage compliant amplification mechanisms

Abstract Stick-slip piezoelectric actuators exhibit the advantages of simple structure, compact size, high resolution, and fast motion speed, enabling millimeter-scale motion range with nanometer-level positioning accuracy. Owing to these unique features, they hold strong potential for high-precision positioning in advanced microsystems, biomedical engineering, optical instrumentation, and other emerging technologies. However, current high-speed stick-slip piezoelectric actuators suffer from the problems of unstable motion, actuator damage, and contact wear due to the high-frequency driving. In this paper, by combining the parallelogram with the triangular mechanism, a two-stage compliant amplification mechanism is integrated into the stick-slip piezoelectric actuator to achieve low-frequency driving and high-speed motion simultaneously. Based on the compliance matrix method, a theoretical model is developed and utilized for structural optimization. Finite element analysis is conducted to verify its accuracy. The performance of the actuator is further investigated by testing the prototype. The experimental results demonstrate that a maximum motion speed of 20.51 mm s −1 is achieved under driving frequency of only 300 Hz and driving voltage of 100 V. Furthermore, the largest vertical load that the piezoelectric driver can support is 700 g when the locking force is 5 N. Compared with the previous studies, the proposed actuator presents good low-frequency driving and high-speed motion performance.