A Cross-Band Piezoelectric Screw Motor Operating in Multimode

To simultaneously meet the requirements of precision instruments for both high speed and high resolution, this study proposes a cross-band piezoelectric screw motor capable of operating simultaneously in the static, quasi-static, and resonant states. The motor is capable of exhibiting different motion characteristics under different working modes. In the static state, high-precision positioning of the motor is achieved by applying direct current to piezo-stacks. In the quasi-static state, low-speed and high-resolution movements of the motor are achieved by providing piezo-stacks with a sawtooth wave signal. In the resonant state, high-speed motion of the motor is realized by giving piezo-stacks sinusoidal signals to excite the stator to resonate. Theoretical and finite element models are established for analysis and simulation. A prototype is manufactured, assembled and tested. Experiment results show that in the static state, the prototype achieves a resolution of 0.5 nm. In the quasi-static state, with a sawtooth wave excitation of 1000 Hz and 400 Vpp, the prototype achieves a velocity of 19.58 mu m/s, a load of 650 g and a resolution of 0.93 nm. In the resonant state, with sinusoidal signals excitation of 10.4 kHz and 150 Vpp, the prototype reaches a velocity of 8.5 mm/s and a load of 3600 g.