Deflection behavior of a piezo-driven flexible actuator for vacuum micropumps

- We developed a piezo-driven flexible actuator to drive a vacuum micropump.
- The solution to eliminate undesired drift is addressed using inverse kinematics.
- The performance was investigated in terms of the deflection and negative pressure.
- The proposed micropump produces maximum negative pressure of 2.45 kPa at 13.2 kHz.

This paper proposes the development of a piezo-driven flexible actuator that creates displacement to drive a vacuum micropump. This actuator consists of parallel flexible amplification mechanisms and piezoelectric actuators. The flexible mechanism relies on its own deformation to amplify the displacement of the piezoelectric actuators. An elastic model is established to estimate the deflection behavior and the effects of its geometric relationship. The finite element method is employed to validate the design and analysis. An experimental investigation is performed to study the deflection and negative pressure. Conclusion is reached that the deflection of the flexible actuator is sensitive to the initial incline angle of the bridge arm. The displacement amplification ratio is not related to the material. An increase in compliance of the flexure hinges can improve the deflection behavior. The proposed actuator produces a displacement of 12.6 μm at a voltage of 54 V. The central rotational symmetry with multiple linkages increases the robustness against radial parasitic displacement.