Enhancement of In-Position Stability Performance in Magnetic Levitation Fine Stages Through Structural Mode Reinforcement

Precision stages have been extensively researched and developed due to their broad range of applications across various fields. Magnetic levitation stages, in particular, control a floating top plate with six degrees of freedom without mechanical coupling. Consequently, the in-position stability performance of magnetic levitation stages is crucial, as it determines the overall stage performance and regulates manufacturing efficiency. Traditionally, efforts to enhance stability have primarily focused on improving the performance of sensors and actuators. This study introduces a novel approach that significantly improves in-position stability by adding specially designed reinforcement components. These components either convert an open frame structure to a closed one or increase the structural stiffness of the stage. Through modal analysis using the Finite Element Method (FEM), the modal shape across the stage was assessed and structurally weak parts were identified. The addition of reinforcement components resulted in a marked improvement in in-position stability, with the root-mean-square displacement values decreasing by 60.5% and 50.0% along the x and y axes, respectively. Moreover, these improvements were predictable through the use of FEM. Given its simplicity and cost-effectiveness, this method is proposed as a promising new strategy to enhance the performance of precision stages.