**4. Conclusions**

A novel stick-slip piezoelectric actuator with a lever mechanism was designed, fabricated, and tested in this research. A lever mechanism set in the stator was employed to increase the displacement of the actuator by amplifying the displacement of the driving foot. Subsequently, a long flexure hinge was used to pre-tighten the piezoelectric stack and eliminate the lateral o ffset error of the frame structure in the stator. Based on the modeling analysis and FEM analysis, the working principle was introduced, and the parameters of the stator were designed to meet the requirements. After the fabrication of a prototype, a vibration test of the stator and a performance test were conducted to validate the theoretical results. When a sawtooth wave with a voltage of 150 V and a frequency of 150 Hz was applied, the maximum velocity of the actuator was 1.8 mm/s. The actuator could obtained the minimum step distance of 0.875 μm from the resolution test. The results have confirmed that the design of the frame structure with a lever mechanism ensures that the actuator can undertake long-travel, fast response, and high precision linear motion.

**Author Contributions:** Conceptualization, Writing—review, Project administration and Funding acquisiton: W.H.; Methodology, Validation, Writing—original draft preparation, editing: M.S.

**Funding:** This research is funded by the Guangzhou Municipal University research projects (No. 1201610315), The Science and Technology novel Research Team Program in Higher Educational Universities of Guangdong Province (2017KCXTD025), the Research Foundation of the Nanjing Institute of Technology (YKJ201901), and the Produce-Learn-Research projects (No. CXY2013NH09).

**Conflicts of Interest:** The authors declare no conflict of interest.
