A strain amplifying piezoelectric MEMS actuator

Abstract

A micro-scale, high-force, large displacement and low-voltage piezoelectric actuator has been developed using a compact strain amplifying flextensional mechanism. The device is fabricated using an SU-8 beam structure as an external amplifying mechanism for a thin-film PZT strip (area 11.4 × 10−4 cm2, thickness 0.4 µm) sandwiched between Pt top and bottom electrodes. Each actuator ‘cell’ can be arrayed in series and/or in parallel to accommodate different force/displacement requirements. Testing of the initial prototype design showed a maximum blocking force of 55 µN and a peak displacement of 1.18 µm at 10 V. Fabricated devices consisting of three actuator cells in series were tested, demonstrating a strain amplification ratio in excess of 10:1 per cell.

Folding assembly of micro-actuators

“…The design of the contractive strain amplifier having flexure hinge mechanism is modified from the previous work which demonstrated elongational strain amplifica- tion [11]. Fig.…”

The Potential of MEMS for Advancing Experiments and Modeling in Cell Mechanics

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Thin-film piezoelectric and high-aspect ratio polymer leg mechanisms for millimeter-scale robotics

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