High-frequency symmetric dual-piezoelectric-actuated compliant microgripper with interchangeable end-effectors

Abstract A symmetric dual-piezoelectric-actuated microgripper with an interchangeable end-effector is presented for micro/nano-manipulation. The design integrates a triangular amplification mechanism with a lever mechanism, achieving compactness and enhanced displacement transmission. Finite element analysis was employed to investigate the effects of hinge radius and structural angle on amplification ratio, natural frequency, and stress distribution: the amplification ratio increases monotonically with R , while natural frequency decreases with R , and maximum stress exhibits a nonlinear trend with a minimum at R ≈ 0.85 mm; for θ , the amplification ratio and natural frequency first increase and then decrease (peaking at θ ≈ 98° and θ ≈ 96°, respectively), while maximum stress decreases nonlinearly with increasing θ. Subsequent stiffness optimization was conducted through threaded fixation, actuator interface reinforcement, and a stainless-steel sandwich housing. Experiments confirmed the effectiveness of the design. The prototype achieved a natural frequency of 1040 Hz and a displacement amplification ratio of 14.2, with maximum output obtained under a preload of 0.23 Nm. The interchangeable end-effectors have successfully demonstrated the capability to grip 88 μ m wires, glass microtubes, and AFM probes. Compared with similar devices, the proposed microgripper maintains compact size while achieving higher dynamic performance, reducing resonance risk. These results highlight its potential for MEMS assembly, biological sample handling, and other precision manipulation tasks.