A V-block three-probe error separation technique for portable measurement of cylindricity

Abstract

A three-probe error separation technique with a novel V-block for measuring and reconstructing a cylindrical profile is presented. The V-block has two tandem V-shaped planes and three displacement probes mounted in one section. During the measurement, the V-block is put onto the measured cylinder, and the two V-shaped planes contact with the cylinder when the cylinder rotates, which make the measurement of cylindrical profile immune to the radial error motions of the spindle. Three probes target each cross-section of the cylinder to collect the data. From the outputs of the probes, the least squares circle center vector of each cross-section is determined via an error separation model built in accordance with the respective relationships of the cross-sectional profiles of the cylinder and error motions of the V-block. Theoretical analysis and numerical validations proved that this technique can accurately detect the median line profile of the cylinder, and the anti-interference capability can be moderately improved by the modified error separation models based on two measuring strategies. This technique realized theoretically full harmonic error separation with the minimum number of probes, accurately detected the spatial median line of the cylinder. Further, high-precision reconstruction of the cylindrical profile was achieved. Integrating the V-block with a laser measurement system can yield a portable system for in-situ measurement cylindricity. It is foreseeable that this technique will garner more attention for future applications.