Machining, Measurement, and Control Laboratory

Vision-based measurement of motion errors for machine tools
Soichi Ibaraki, Yusuke Tanizawa

This paper presents vision-based measurement of two-dimensional positioning errors of machine tools. A pre-calibrated grid plate is used as an artifact. The position of a grid point is measured in an image captured by a charge coupled device (CCD) camera attached to a spindle. Unlike conventional two-dimensional digital scales, the vision-based measurement can target the artifact in any orientation, and thus can be applied to error calibration of a rotary axis. The paper demonstrates experimental applications of the vision-based measurement to the measurement of 1) static error motions of linear axes, 2) static radial error motion of a rotary axis, and 3) dynamic radial error motion of a rotary axis.
Keywords: Vision-based measurement, volumetric accuracy, camera, grid, five-axis machining center.