A Novel Coupling Amplification Mechanism for Improving Stepping Characteristics of Stick-Slip Piezoelectric Actuators

Piezoelectric actuators, representing prominent products in the realm of small-sized precision actuators, exhibit advantages such as low energy consumption and high output force, coupled with relatively mature technology. However, existing piezoelectric actuators, despite enhancing motion speed through the utilization of one or multiple displacement amplification mechanisms, face a challenge in significantly increasing the stepping displacement, especially in compact spaces and under low-frequency conditions. To address the challenge of limited stepping displacement, this paper proposed a novel coupling amplification mechanism. The coupling amplification effect of two displacement amplification mechanisms can be achieved using only one piezoelectric stack. Subsequently, the excellent displacement amplification effect of the proposed mechanism is demonstrated through pseudo-rigid body and finite element methods. Finally, the proposed flexible hinge mechanism is applied to the actuator design, effectively improving both the stepping displacement and speed.