Abstract
Many types of positioning devices have been developed for machine tools. Of these, state-of-the-art ultra-precision vertical positioning devices most often employ pneumatic balancing cylinder(s) along with an electric linear motor to achieve energy-efficient ultra-precise positioning. However, the relationship between the accuracy of ultra-precision positioning and fluctuation of pressure in a balancing cylinder is currently unknown. In order to further clarify this relationship, we fabricated an electro-pneumatic hybrid ultra-precision vertical positioning stage and used it to investigate the relationship between the accuracy of ultra-precision positioning and pressure fluctuations in a balancing cylinder. Next, a high precision quick response pneumatic regulator (HPQR) that had been previously developed by the authors was applied to pressure control of the balancing cylinder using the newly developed positioning stage. Our experimental results indicate the superiority of the proposed method compared with conventional methods.
