First domestic comparison of ball plate calibration in Japan

摘要

Ball plates have been increasingly used for checking the performance of coordinate measuring machines (CMMs) in Japan. In future, the ball plate will become a popular gauge for checking or calibrating the CMM in Japan. Currently, only the National Metrology Institute of Japan (NMIJ) can calibrate the ball plate in Japan. There are no other institutes or calibration laboratories able to calibrate the ball plate. Therefore, we organized a ball plate round-robin measurement to create the opportunity to relay our calibration technique to other institutes. This is the first domestic comparison of a ball plate calibration in Japan. Sixteen institutes including NMIJ participated in the comparison. In this round-robin measurement, we formed two groups and supplied two ball plates (KOBA 420x420 mm, RETTER 420x420 mm) and two material standards of length made by NMIJ for this round-robin measurement. The round-robin measurement took place from October 2003 to September 2004. We describe the results of the comparison in this paper.