Elastic Deformation Error Model for Calibration and Compensation of Parallel Kinematic Mechanism Machine Tool
Tetsuya Matsushita*, Hiroshi Ueno*,
and Atsushi Matsubara**
*OKUMA Corporation, 5-25-1 Oguchi-cho, Niwa-gun, Aichi 480-0193, Japan
**Department of Micro Engineering, Graduate School of Engineering, Kyoto University, Yoshidahonmachi, Sakyo-ku, Kyoto 606-8501, Japan
In the motion error of parallel kinematic mechanism machine tools, the elastic deformation caused by external forces, such as gravity, as well as the kinematic parameter error, is a significant factor. Internal forces generated by the rotational resistance of passive joints also deform mechanical components. In this paper, an elastic deformation error model that can deal with external and internal forces is presented. A compensation system and a calibration method of kinematic parameters employing this model are also presented. It is experimentally verified that this calibration method and compensation system improve the motion accuracy of a parallel kinematic mechanism machine tool.
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