A long stroke linear stepping piezoelectric actuator using two longitudinal-bending hybrid transducers

Abstract A linear stepping piezoelectric actuator using two longitudinal-bending hybrid transducers is proposed and tested in this work. The proposed actuator uses the operating principle of two feet walking to accomplish the linear driving with long stroke. The operating principle is discussed in detail: two transducers operated under longitudinal-bending hybrid motions are used together to push a runner linearly step-by-step; the longitudinal motions are used to lock the runner by the static friction forces, while the bending motions are used to drive the runner linearly. Totally, four exciting signals are applied on the two transducers, the phase shifts among them are used to control the movement direction of the runner. A prototype of the stepping piezoelectric actuator is fabricated to test the output performances. The experiment results show that a long travel (depends on the length of the runner) motion with resolution of 50 nm is achieved. The maximum stepping displacement is tested to be 10.75 µm under voltage of 400 Vp-p, the maximum speed is 720.65 µm/s under frequency of 60 Hz and the maximum thrust is about 15 N.