Abstract: The main factors affecting the dynamic errors of coordinate
measuring machines are analyzed. It is pointed out that there
are two main contributors to the dynamic errors: One is the
rotation of the elements around the joints connected with air
bearings and the other is the bending of the elements caused by
the dynamic inertial forces. A method for obtaining the
displacement errors at the probe position from dynamic
rotational errors is presented. The dynamic rotational errors
are measured with inductive position sensors and a laser
interferometer. The theoretical and experimental results both
show that during the process of fast probing, due to the dynamic
inertial forces, there are not only large rotation of the
elements around the joints connected with air bearings but also
large bending of the weak elements themselves.
Key words: Coordinate
measuring machine Dynamic error Laser interferometer Inductive
position sensor
*
This project
is supported by the 21st Century Youth Science Foundation of Tianjin. Manuscript received on
June 28, 1997; revised manuscript February 25, 1998
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