Topology optimization design of a novel piezoelectrically actuated dual-axis micro/nano-positioning stage

Abstract

Traditional micro/nano-positioning stages often rely on rigid positioning mechanisms, which are prone to friction, assembly errors, and structural gaps, resulting in limited positioning accuracy and operational instability. To overcome these limitations, this paper proposes a novel dual-axis piezoelectrically actuated micro/nano-positioning stage using a topology optimization method. A multi-objective and multi-constraint optimization design model was developed using a three-density technique based on the solid isotropic material with penalization (SIMP) interpolation approach to represent and analyze its topology. The model uses a combined objective function of natural frequency and output displacement, with constraints including motion-coupling between the input/output-ports, compliance, and displacement amplification ratio, among other performance indicators. Through the optimization of design variables using the global convergence moving asymptote (GCMMA) algorithm, a robust micro/nano-positioning stage with multi-degree-of-freedom capabilities, high-bandwidth, and large-stroke was successfully developed. Two numerical case studies were conducted, demonstrating effective motion decoupling, improved structural performance, and enhanced positioning accuracy. Finite element analysis (FEA) was carried out to validate the theoretical design, confirming its mechanical feasibility and robustness. The results demonstrate that the proposed method not only enables the reliable functional implementation of the micro/nano-positioning stage but also substantially improves its positioning accuracy and operational stability.