Design and Optimization of a Large-Stroke XY Compliant Positioning Stage Based on Cross-Axis Flexure Pivot

Abstract

Abstract. XY compliant positioning stages (CPSs) are widely utilized in precision engineering for their high-precision, frictionless motion capability. However, existing XP CPSs face challenges in simultaneously achieving a large motion stroke, a compact structure, and minimal parasitic rotation. To address this challenge, this article proposes a novel large-stroke XY CPS based on cross-axis flexure pivots (CAFPs). The design employs a multilayer, rotational mirror symmetry architecture to minimize parasitic rotation and footprint. To analyze its performance, a comprehensive static model is developed to predict the stage’s kinematic behavior and stiffness properties. Subsequently, a multiobjective optimization is implemented, using key geometric parameters as variables, to systematically minimize both parasitic rotation and stiffness variation. The optimized prototype demonstrates a large 18.21–18.10 mm workspace, with parasitic rotation and stiffness variation reduced by 45.89% and 42.14% respectively, showcasing its excellent compactness and precision. Experimental results validate both the accuracy of the static model and the effectiveness of the proposed design and optimization methodology, demonstrating its potential for advanced micropositioning applications.