Design of a compact long-stroke high-precision rigid-flexible coupling motion stage driven by linear motor

This paper proposes a long-stroke rigid-flexible coupling motion stage (RFCMS) that employs flexure hinges to compensate the friction dead zone through elastic deformation. Specifically, based on the need for a motion stage with a compact structure, this paper proposes a new rigid-flexible coupling structure (RFCS) design with a horizontally installed linear motor and asymmetric flexure hinges. Further, end leaf springs are introduced to enhance the stiffness in the non-motion direction. In addition, the nonlinear interior-point optimization method is used to obtain the optimal structural parameters of the flexure hinges for higher deformation uniformity. To verify the effectiveness of the proposed design, a motion stage benchmarked with Aerotech’s PRO190LM (stroke, 500 mm) is developed, which realizes bidirectional repeatability (BR) of ±0.25 µm. The BR is improved by 37.5 %. Moreover, the deformation uniformity of the stage is ±3.7 %, which proves that the proposed RFCMS can achieve high deformation uniformity and high precision.