Design of Piezoelectric Inertial Actuator with Wedge‐shaped Foot Structure for Cell Manipulation

Abstract

Aiming at the performance requirements of positioning accuracy and stability of piezoelectric inertial actuators in fields including micro‐operation and biomedical engineering, a piezoelectric inertial actuator with wedge‐shaped friction foot structure using bimorph films is proposed in this paper. The wedge‐shaped friction foot structure can adjust the friction force in different driving stages, which suppresses the backward motion and effectively improves the output performance of the actuator. And the bimorph films are processed by Micro Electromechanical Systems (MEMS) manufacturing process technology. It enables the actuator to move steadily with a small tip mass and facilitates the miniaturization of actuator. The simulation model is constructed based on the dynamic model of actuator and the prototype parameters are optimized from the results of simulation tests. Then a series of output performance experiments are carried out. Experimental results show that the proposed actuator has the advantages of high resolution, stability, and displacement linearity. And the highest resolution of 0.035 µm is achieved. Depending on above results, the cell drug injection simulation experiments are successfully conducted. The success of experiments shows that the prototype has good output performance and great application potential and value in the field of cell manipulation.