A Novel Linear Walking Type Piezoelectric Actuator Based on the Parasitic Motion of Flexure Mechanisms

A walking-type piezoelectric actuator based on the parasitic motion of flexure mechanisms is proposed in this paper. With the help of the parasitic motion of the asymmetrical flexure mechanism, the conventional walking-type piezoelectric actuator with four piezoelectric elements and four input signals is simplified to be with only two piezoelectric elements with two input signals. The finite element method has been utilized to quantitatively investigate the parasitic motion of the asymmetrical flexure mechanism. A series of experiments have been carried out to investigate the working performance (stepping performance, speed performance, and load performance) of the proposed walking-type piezoelectric actuator. The results indicate that the minimum stepping displacement is <inline-formula> <tex-math notation="LaTeX">$\Delta L=0.18 \,\,\mu \text{m}$ </tex-math></inline-formula>, under the condition of <inline-formula> <tex-math notation="LaTeX">$U=30$ </tex-math></inline-formula> V and <inline-formula> <tex-math notation="LaTeX">$f=1$ </tex-math></inline-formula> Hz. In addition, the maximum motion speed is <inline-formula> <tex-math notation="LaTeX">$V_{\mathrm {s}}=39.78 \,\,\mu \text{m}$ </tex-math></inline-formula>/s in the case that <inline-formula> <tex-math notation="LaTeX">$U=100$ </tex-math></inline-formula> V and <inline-formula> <tex-math notation="LaTeX">$f=20$ </tex-math></inline-formula> Hz. This paper confirms the feasibility of the utilization of parasitic motion in the simplification and design of the walking-type piezoelectric actuators.