Design and Experimental Research of a Rotary Micro-Actuator Based on a Shearing Piezoelectric Stack

The working principle of a rotating micro-actuator based on a piezoelectric stack was theoretically analyzed and experimentally verified. The actuator is compact in structure, and the key component is the shearing piezoelectric stack. The piezoelectric stack is used to drive the micro-rotor via an electromechanical transition, which produces high-speed rotation of the micro-rotor. We first established the dynamic model of the micro-actuator and numerically analyzed the motion of this model. The step displacement output was observed by simulation, and the step increment is quite large. For experimental verification, we fabricated the piezoelectric micro-actuator with a size of 12 mm × 10 mm × 8 mm and mass of 4.12 g and conducted a series of experiments. The results show qualitative agreement with the theoretical results; the maximum output speed of the micro-actuator is 5.86 × 10 5 μ rad/s, and the motion resolution is 0.64 μ rad, which is greater than that of most traditional piezoelectric actuators. The proposed micro-actuator offers superior performance in driving of selected small objects, such as in micro-/nano-processing and cell operation.