Design and Analysis of a Piezo-Driven Precision Positioning Stage Suitable for XBPM

Abstract X-ray beam position monitor (XBPM) is an indispensable device in the fourth-generation synchrotron light sources. However, the vacuum micro-positioning stage suitable for key components in advanced light sources has received scant attention. Aiming at the demand of high positioning accuracy and simple position adjustment of XBPM, an XZ stacked piezo-driven precision positioning stage is proposed in this paper. The stage configuration is decoupled, which can realize independent translations in X and Z directions. The overall scheme is non-closed and the selection of material and actuator in special occasion is focused, which is suitable for general and ultra-high vacuum system. In addition, the static and dynamic characteristics of the precision positioning stage are verified with finite element analysis (FEA), and the prototype test system is built. The experimental results indicate that the workspace under closed-loop feedback control is 51.39 μm × 35.07 μm, which is almost consistent with the simulation results. Furthermore, the output displacement linearity, maximum output coupling error rate and actual resolution of the stage are assessed. The impact of environmental fluctuation on actual resolution is also quantitatively evaluated. According to the simulated and test results, the designed stage achieves the expected performances and can meet the demands of micronano positioning accuracy and motion decoupling of XBPM.