Design Of Large Stroke Gas-Lubricated Precision Positioning Stage System

With the continuous development of precision manufacturing and precision positioning technology in the field of surface profile measurement,the requirements of high-precision stage for precision measurement is also increasing.The traditional roller screw with the stepper or servo motor structure of the motion stage is reliable and cost-effective,and thus has been widely used.However,the manufacturing error of the roller screw in this structure cannot be eliminated,which causes the backlash error of the motion platform and affects the final measurement accuracy.Based on this,this paper designs a large stroke GasLubricated precision positioning stage,which adopts the form of air-floating guide rail and linear motor to eliminate backlash error and improve measurement accuracy.It can be used for surface profile measurement.The research work of the paper is as follows:1.The precision displacement table of classical and new support structures at home and abroad is studied,and a large stroke Gas-Lubricated precision positioning stage is designed.The key component structure is designed and calculated,and the threedimensional model of the Gas-Lubricated precision positioning stage is established,and the overall control system of the drive control is determined.2.Based on the working principle of air bearing,the performance of the throttle is compared and analyzed,and the appropriate air floating form is selected.The formula for calculating the bearing capacity and stiffness of the air bearing is derived theoretically.The effects of throttling aperture,air pressure,film thickness and eccentricity on the bearing capacity and stiffness of the air bearing guide and the slider are analyzed.The parameters of the air bearing support form are designed.3.Based on the static and dynamic characteristics theory,the static and dynamic characteristics of the air-floating working platform are analyzed.The static stress of the airfloating platform is analyzed theoretically and simulated.The dynamic model of the workbench is established,the simulation modal analysis is carried out,and the experimental test of the air-floating workbench is carried out to obtain the actual natural frequency.4.The experimental device of the air-floating workbench measurement system is built and the system test software is designed.The accuracy of the workbench prototype is tested,and the measurement and measurement data is compensated to improve the measurement accuracy.Finally,the processed spherical surface is subjected to actual contour measurement.The results show that the precision displacement table can meet the contour measurement requirements in the field of precision measurement.