Pneumatic Servo Bearing Actuator with Multiple Bearing Pads for Ultraprecise Positioning
Shuhei Tsujimura*, Yusuke Hashimoto*, Takashi Matsuoka**,
Tomoko Hirayama**, and Katsumi Sasaki***
*Graduate School of Mechanical Engineering, Doshisha University, 1-3 Miyakodani, Tatara, Kyotanabe, Kyoto 610-0394, Japan
**Department of Mechanical Engineering, Doshisha University, 1-3 Miyakodani, Tatara, Kyotanabe, Kyoto 610-0394, Japan
***Pneumatic Servo Controls Ltd., 2266-22 Anagahora, Shimo-Shidami, Moriyama-ku, Nagoya 463-0003, Japan
With the increase in demand for semiconductor products, ultrafine linear patterning technologies for Large-Scale Integrations (LSIs) have been making progress. The requested positioning accuracy in such ultraprecise apparatuses is of nanometer order. To meet such specific needs, the research and development of a variety of actuators has been necessary. Our laboratory has developed a ‘Pneumatic Servo Bearing Actuator (PSBA),’ a novel actuator that uses pneumatic servo technology for ultraprecise positioning. Our past studies have showed that the minimum resolution of PSBA was almost 6 nm, even under open loop control; thus, we concluded that the PSBA was a promising actuator in advanced ultraprecise positioning systems. However, the stroke of the PSBA was comparatively short. To expand the stroke of the actuator, we proposed and developed a new PSBA with multiple thin thrust-bearing pads. The main purpose in this study is to investigate the positioning properties of the new PSBA with multiple thrust bearing pads. The obtained characteristics of the PSBA can be enumerated as follows. (1) The PSBA with multiple bearing pads achieves a longer stroke than the PSBA with a single pad. (2) The difference in the thickness of the bearing pads affects the dynamic characteristics of the actuator. (3) The minimum positioning resolution of the developed PSBA with twenty-nine bearing pads is about 2 – 4 nm with feedback control.
-  T. Oiwa, M. Katsuki, M. Karita, W. Gao, S. Makinouchi, K. Sato, and Y. Ohashi, “Questionnaire Survey on Ultra-Precision Positioning,” Int. J. of Automation Technology, Vol.5, No.6, pp. 766-772, 2011.
-  J. Otsuka, S. Ichikawa, and Y. Yamaguchi, “Development of Small Ultraprecision Displacement Sensor and Small Ultraprecision Positioning Device with 1nm Resolution,” J. JSPE, Vol.69, No.10, pp. 1428-1433, 2003.
-  J. Otsuka, S. Ichikawa, T. Masuda, and K. Suzuki, “Development of a Small Ultraprecision Positioning Device with 5nm Resolution,” Measurement Sciencen and Technology, Vol.16, No.11, pp. 2186-2192, 2005.
-  H. Tachikawa, M. Fukuda, K. Sato, and A. Shimokobe, “Ultra Precision Positioning Using Air Bearing Lead Screw,” Vol.66, No.645, pp. 1559-1566, 2000.
-  P. Gao, H. Tan, and Z. Yuan, “The Design and Characterization of a Piezo-Driven Ultra-Precision Stepping Positioner,” Measurement Science and Technology, Vol.11, No.2, N15-N19, 2000.
-  H. Mizumoto, Y. Yabuta, S. Arii, M. Yabuya, and Y. Tazoe, “A Dual-Mode Pico-Positioning System Using Active Aerostatic Coupling,” Int. J. of Precision Engineering and Manufacturing, Vol.8, No.2, pp. 32-37, 2007.
-  Z. Rao, “Nonlinear Modelling and Control of Servo Pneumatic Actuators,” IEEE Trans. Control Systems Technology, Vol.16, No.3, pp. 562-569, 2008.
-  M. H. Tsai, T. Y. Hsu, K. R. Pai, and M. C. Shih, “Precision Position Control of Pneumatic Servo Table Embedded with Aerostatic Bearing,” Vol.2, No.4, pp. 940-949, 2008.
-  M. Kadotani, T. Kitagawa, S. Katto, T. Hirayama, T. Matsuoka, H. Yabe, and K. Sasaki, “Development of Pneumatic Servo Bearing Actuator for Nanometer Positioning,” Int. J. Automation Technology, Vol.3, No.3, pp. 249-256, 2009.
-  T. Wang, M. Cai, K. Kawashima, and T. Kagawa, “Modelling of a Nozzle-Flapper Type Pneumatic Servo Valve Including the Influence of Flow Force,” Int. J. of Fluid Power, Vol.6, No.3, pp. 33-43, 2005.
-  H. Yabe, H. Mori, H. Asakawa, and M. Kihara, “A Study on Characteristis of Externally Pressurised Gas Thrust Bearing with Surface-Restriction Compensation,” Trans. JSME C, Vol.45, No.389, pp. 100-107, 1979. (in Japanese)
-  A. Mori, “Basic Design for Externally Pressurized Gas Bearings,” Text of Gas Bearing Workshop, Japanese Society of Tribologists, 1991. (in Japanese)
-  T. Hirayama, K. Sasaki, and H. Yabe, “Pneumatic Servo bearing Actuator for Ultraprecise Positioning (1st Report) – Presentation of Fundamental Characteristics through the System Representation –,” J. JSPE, Vol.74, No.10, pp. 1086-1091, 2008. (in Japanese)