Study of a Precision Pneumatic Positioning Device Using PZT Dither
Yung-Tien Liu*, Kuo-Ming Chang**, and Huang-Ren Lee*
*Department of Mechanical and Automation Engineering, National Kaohsiung, First University of Science and Technology, 2 Jhuoyue Rd., Nanzih, Kaohsiung 811, Taiwan, R.O.C.
**Department of Mechanical Engineering, National Kaohsiung, University of Applied Sciences, 415 Chien Kung Rd., Sanmin, Kaohsiung 807, Taiwan, R.O.C.
A piezoelectric (PZT) actuator featuring a high frequency response is employed to serve as a highfrequency dither and to compensate for the nonlinear motion characteristic of a pneumatic positioning device. To examine the function of the PZT dither, system identification based on a linear model for describing the positioning device was performed. To obtain the most suitable actuating parameters of the PZT dither, the Taguchi method was employed. Using the optimal parameters, the positioning system implemented by the PID controller was configured. For a target position of 4 mm, position control with a positioning accuracy under 0.1 µm was demonstrated. Compared to the pneumatic positioning device using a traditional controller, the device presented in this study features better positioning ability.
-  J. Song and Y. Ishida, “A Robust Sliding Mode Control for Pneumatic Servo Systems,” Int. J. of Engineering Science, Vol.35, pp. 711-723, 1997.
-  M. Taghizadeh, A. Ghaffari, and F. Najafi, “Improving Dynamic Performances of PWM-driven Servo-pneumatic Systems via a Novel Pneumatic Circuit,” ISA Transactions, Vol.48, pp. 512-518, 2009.
-  M.-C. Shih and M.-A. Ma, “Position Control of a Pneumatic Cylinder using Fuzzy PWM Control Method,” Mechatronics, Vol.8, pp. 241-253, 1998.
-  M. Parnichkun and C. Ngaecharoenkul, “Kinematics Control of a Pneumatic System by Hybrid Fuzzy PID,” Mechatronics, Vol.11, pp. 1001-1023, 2001.
-  M. Kadotani, T. Kitagawa et al., “Development of Pneumatic Servo Bearing Actuator for Nanometer Positioning,” Int. J. of Automation Technology, Vol.3, pp. 249-256, 2009.
-  Y.-T. Liu, C.-H. Lee, and R.-F. Fung, “A Pneumatic Positioning Device Coupled with Piezoelectric Self-moving Mechanism,” Asian J. of Control, Vol.6, No.2, pp. 199-207, 2004.
-  M.-H. Chiang, C.-C. Chen, and D.-N. Tsuo, “Large Stroke and High Precision Pneumatic-Piezoelectric Hybrid Positioning Control using Adaptive Discrete Variable Structure Control,” Mechatronics, Vol.15, pp. 523-545, 2005.
-  Y.-T. Liu and C.-C. Jiang, “Pneumatic Actuating Device with Nanopositioning Ability Utilizing PZT Impact Force Coupled with Differential Pressure,” Precision Engineering, Vol.31, pp. 293-303, 2007.
-  A. A. Pervozvanski and C. Canudas-de-Wit, “Asymptotic Analysis of the Dither Effect in Systems with Friction,” Automatica, Vol.38, pp. 105-113, 2002.
-  T. Hägglund, “A Friction Compensator for Pneumatic Control Valves,” J. of Process Control, Vol.12, pp. 897-904, 2002.
-  Y.-T. Liu, C.-C. Wang et al., “Characteristic Study on Precision Pneumatic Actuating Device using Piezoelectric Dither,” Proc. of the 2nd Int. Forum on Systems and Mechatronics, pp. 37-42, 2007.
-  M.-C. Shih and S.-I. Tseng, “Identification and Position Control of a Servo Pneumatic Cylinder,” Control Eng. Practice, Vol.3, No.9, pp. 1285-1290, 1995.
This article is published under a Creative Commons Attribution-NoDerivatives 4.0 International License.