Design of a Flexible Hinged Piezoelectric Viscous Slip Actuator with Retraction Suppression

In order to solve the displacement regression phenomenon of piezoelectric viscous-slip actuators, this paper proposes a lever-type flexible hinge mechanism that uses two sets of piezoelectric stacks to move the slider in both directions and efficiently suppress the displacement regression phenomenon. First, the overall dimensional parameters of the drive are designed, the device is modeled using 3D software, and the driving principle is analyzed. Then a theoretical model is built based on the lever amplification principle to derive the relevant expressions for the piezoelectric viscous slip actuator under sawtooth wave type voltage signals. The piezoelectric stack is simulated and analyzed with COMSOL Multiphysics to obtain the modal and stress-displacement clouds of the flexible hinges. Finally, a prototype was built for experimental testing, and the slider in the device was able to achieve smooth motion and effectively suppress the displacement regression phenomenon. The input voltage of piezo stack A is 100 V, the input voltage of piezo stack D is 150 V, the input frequency is 212 Hz, the maximum output displacement of single-step drive is 46.6 μm, and the amplification ratio of flexible hinge input to output is 2.59. The piezoelectric viscous-slip actuator was verified to be able to achieve effective drive and suppress back-off.