Design and validation of a piezoelectric-based compliant mechanism for micro-displacement instrumentation

To address the limited displacement range of piezoelectric stack actuators in precision instrumentation, this study presents a novel compliant amplification mechanism designed to enhance stroke output while maintaining compactness and mechanical reliability. The proposed device, structured in a rectangular parallelepiped configuration, incorporates a two-stage lever system combining circular and rectangular flexure hinges to achieve high amplification with minimal deflection. The mechanism is specifically tailored for micro-displacement actuation and sensing applications, such as those found in high-resolution positioning systems or scientific instruments. Finite Element Analysis (FEA) was used to model and optimize the mechanical performance, with results validated through experimental testing. The device demonstrated a displacement amplification factor of 16.79, converting an input stroke of 0.04269 µm from a piezoelectric actuator to an output of 0.7167 µm, all while maintaining stress levels well below the yield limit of the material. This work contributes a validated, compact electromechanical component suitable for integration into advanced instruments requiring precise control and displacement amplification, with potential applications in biomedical instrumentation, micro-robotics, and high-precision assembly systems.