Displacement amplifier for piezoelectric actuator based on honeycomb link mechanism

This study proposes a compact and array-type design of a mechanical amplifier for piezoelectric actuators. The amplifier emulates in-plane deformation of a specific honeycomb having bow-tie-type reentrant cells. When a multilayer piezoelectric actuator causes the elongation of a cell of the amplifier in the longitudinal direction, the cell causes expansion in the transverse direction with amplification depending on its geometry. For ease of fabrication of the amplifier, a plate having periodic patterns of two holes and a slit is proposed, in which all walls and corners of the cell are replaced with rigid links and elastic hinges, respectively. Compactness of an amplified piezoelectric actuator based on the honeycomb link mechanism is demonstrated by using prototypes of uniaxial actuators and XY stages. Furthermore, theoretical formulas are discussed, which are used in the design of the amplified actuators.