Fig. 1. Structure and d33 effect mode of stacked PZT actuator. (a) Structure of stacked PZT actuator;

Fig. 2. Bending mode of stacked PZT actuator. (a) Tilting shape of 300 mm PFSM; (b) force and bending shape analysis of stacked PZT actuator; (c) microelement analysis of stacked PZT actuator

Fig. 3. Deformations and stresses of the actuator under different driving voltage amplitudes. (a) Amplitude is 50 V; (b) amplitude is 200 V; (c) amplitude is 350 V; (d) amplitude is 500 V

Fig. 4. Analyses of stresses of stacked PZT actuator under different driving voltage amplitudes

Fig. 5. Shapes and stresses PZT layer under different bending stiffnesses of PZT hinge. (a) Bending stiffness is 0.16 N·m²; (b) bending stiffness is 2.5 N·m²; (c) bending stiffness is 12.56 N·m²; (d) bending stiffness is 40.2 N·m²

Fig. 6. Analyses of stresses of stacked PZT actuator under different bending stiffnesses of PZT hinge

Fig. 7. Shapes and stresses PZT layer under different voltage frequencies. (a) Frequency is 60 Hz; (b) frequency is 120 Hz; (c) frequency is 180 Hz; (d) frequency is 250 Hz.

Fig. 8. Analyses of stresses of stacked PZT actuator under different voltage frequencies

Fig. 9. Distribution of actual value-predicted value and the probability distribution of internal studentized residuals. (a) Distribution of actual value-predicted value for CCD design; (b) probability distribution of internal studentized residuals for Von Miss stress

Fig. 10. （a） Contour map and （b） 3D response surface of Von Miss stress with B_S and F_R