Development and test of a high speed pusher-type inchworm piezoelectric actuator with asymmetric driving and clamping configuration

The pusher type inchworm piezoelectric actuator has the advantages of fast response and wide stroke, but the complex excitation signal sequences limits the output speed and load capacity. An asymmetric driving and clamping configuration along with simplified excitation signal sequences of a high speed piezoelectric actuator is proposed. A lever amplification mechanism is designed to increase the step. A hexagonal output shaft is designed to enhance the clamping force and the load capacity. The pseudo rigid body method is used to build the kinematic and statical model. Statics and dynamics are analyzed through both simulations and experiments. Results show that, when the driving voltage is 80 V, the maximum step is 71μm at the driving frequency of 550 Hz, the maximum speed is 44.69 mm/s at the driving frequency of 650 Hz, the maximum clamp force is 432.2 N, and the maximum load is up to 60 g. Herein, the driving speed and load capacity are significantly improved compared with the traditional structures in the literature.