Title: Improving the speed of a pneumatic stage through positive feedback of calculated stage jerk signal
Authors: Mohebullah Wali; Shinji Wakui
Addresses: Department of Electronic and Information Engineering, Tokyo University of Agriculture and Technology, 2-24-16 Nakacho, Koganei City, Tokyo, 184-8588, Japan ' Department of Electronic and Information Engineering, Tokyo University of Agriculture and Technology, 2-24-16 Nakacho, Koganei City, Tokyo, 184-8588, Japan
Abstract: In this paper, a pneumatic stage is concerned. The stage is moved between two parallel guideways which are fixed on the base plate. The base plate is activated by four coil-type spring isolators. The positive feedback of calculated stage jerk signal (PFBCSJS) is proposed to speedup the stage positioning. This control scheme results in the reduction of stage mass, which leads the positioning speed to improve. The stage jerk signal is calculated by using the relative position and base plate acceleration signals which are respectively measured by an optical encoder and an accelerometer. The reason of using calculated stage jerk signal is to circumvent the use of accelerometer on the stage. This is because if an accelerometer is used, its cable tension for short length or contact to surroundings for long length will respectively make safety or noise problems. Moreover, its output might be saturated for the fast and long stroke positioning due to the lower level of its maximum detection sensitivity. The effectiveness of the proposed control scheme is evidently verified through the experimental results.
Keywords: pneumatic stage; base plate; positive feedback; calculated jerk signal; driving mechanism; PDD² controller; proportional derivative double derivative; feedback control; PI control; spring isolators; positioning speed; semiconductor fabrication; pneumatic actuators; positioning stages.
International Journal of Advanced Mechatronic Systems, 2013 Vol.5 No.5, pp.297 - 305
Received: 08 May 2021
Accepted: 12 May 2021
Published online: 12 Mar 2014 *