A smooth-drive scheme for piezoelectric stage by coupling of stick-slip motion and inertial impact

Abstract

The piezoelectric stick-slip stage is very important in industrial manufacturing and precision machining. However, due to the stick-slip principle, it is inevitable to produce backward motion, which leads to a decrease in precision and efficiency. A novel smooth-drive scheme for piezoelectric stage is proposed by coupling stick-slip motion and inertial impact in this paper. In the coupling counteract phase, the sliding friction force of stick-slip driving mechanism (SDM) is counteract by the impact force of inertial impact driving mechanism (IDM), thus eliminating the backward motion and realizing the smooth driving of the stage. The feasibility of the stage is analyzed by theoretical calculation and transient dynamics simulation. In addition, the designed stage is fabricated and conducted a complete set of experimental tests. The external dimensions of the stage is 45 mm (L) × 24 mm (W) × 22 mm (H), and the mass is 84 g. Experimental results show that the piezoelectric stage can not only achieve smooth driving, but also actively adjust the output smoothness by adjusting the excitation voltage of PZT I and PZT II. The linear fitting correlation coefficient R2 of the displacement curve can reach above 0.999, and it still keeps good smoothness at 200 Hz. The maximum vertical mass load of the stage is 4 kg, which is about 47 times the mass of the stage, and the resolution of stick-slip state is about 85 nm. The scheme has positive reference value in the field of stable and accurate positioning.