Geometric Error Measurement and Identification for Rotary Table Using Double Ballbar
CHEN Jian-xiong1, LIN Shu-wen1, HAN Guo-qiang1, 2
1. School of Mechanical Engineering and Automatic, Fuzhou University, Fuzhou, Fujian 350108, China;
2. Fujian Institute of Research on the Structure of Matter, Chinese Academy of Science, Fuzhou, Fujian 350002, China
Abstract：The derivations of the center of the ball installed on the rotary table are measured by double ballbar with circular paths in the error sensitive directions. Hence, there are nine results measured from three mounting positions of the ball at the same rotation angle, to form four axis location and six motion errors identification model using homogeneous transformation. In addition, the condition number is applied to select the optimum installation parameters of the ballbar. Finally, the measurement and verification experiments are conducted on the four-axis machining center. All the elements of the geometric error can be identified by the proposed method from the measured results with high accuracy and measuring effectively. Then, comparing the predicted value from the identified errors with the measured results by ballbar, it shows that the absolute residual error is less than 0. 003 mm.
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