Design and Control of a Piezo-Driven <i>z</i>-<i>θx</i>-<i>θy</i> Parallel Nanopositioning Stage With Two-Stage Rhombic Amplification Structure

Abstract In this article, a large-stroke compact of z-θx-θy piezoelectric nanopositioning stage and the corresponding control method are designed. A two-stage rhombic amplifying mechanism equipped with piezoelectric actuator (PZTA) is designed, which provides driving energy through flexible lamina deformation. A large-stroke compact piezoelectric nanopositioning stage is designed using four-corner arrangement. Based on the statics analysis, a dynamic model of stage is constructed to analyze the natural frequency and bandwidth. The size optimization algorithm is used to further improve the dynamic response characteristics of the stage. The optimization results are then validated using finite element analysis (FEA). The compound controller employs a rate-dependent model combined with proportional-integral (PI) control. Experimental results demonstrate that the stage configuration achieves nanoscale resolution, a large displacement stroke, and high compactness. Furthermore, the controller exhibits excellent rate-dependent tracking accuracy, precise positioning, and robust dynamic performance.