Novel calibration plate and calibration method for performing length measurement by using calibration plate

Abstract

The invention relates to a novel calibration plate and a calibration method for performing length measurement by using the calibration plate. According to the structure of the novel calibration plate, a calibration plate body is provided with a plurality of positioning balls; the positioning balls are divided into four groups, wherein each group includes two positioning balls; the positioning balls in the A group are located at two sides of a vertical midline of the calibration plate and are symmetrically arranged; the diameter of the positioning balls in the A group is 50mm; the interval between the positioning balls in the A group is 150mm; the diameter of the positioning balls in the B group is 80mm; the positioning balls in the B group are located obliquely below the outer sides of the positioning balls in the A group; the interval between the positioning balls in the B group is 250mm; the diameter of the positioning balls in the C group is 150mm; the positioning balls in the C group are located at the outer sides of the positioning balls in the B group; the interval between the positioning balls in the C group is 400mm; the diameter of the positioning balls in the D group is 150mm; the positioning balls in the D group are located at the outer sides of the positioning balls in the C group; and the interval between the positioning balls in the D group is 750mm. The calibration method includes the following steps that: the difference of measurement indicating length La between positioning balls in each group and actual dimension between positioning balls in each group of the novel calibration plate, namely a calibration length truth value Lr, is obtained, so that a measurement error E can be obtained; an optical 3D measurement system is adjusted until the error satisfies accuracy requirements, and calibration work can be completed. This method is simple, quick, convenient and practical.

Description

technical field [0001] The invention relates to a method for calibrating length measurement errors for an optical three-dimensional measurement system for area scanning. In particular, a new type of calibration plate is designed, which is specially used for the error calibration of the measurement system. Background technique [0002] An optical 3D measuring system is a general-purpose measuring and testing device that can be configured by the user to suit specific measuring tasks. Their sensors consist of several parts, including one or several image sensors (cameras), one or several projection systems for projecting structured light onto the surface of an object for measurement, or a textured illumination for illuminating any surface present system. Such as: measurement systems based on text projection or Moore text technology, and photogrammetry or scanning systems with area scanning capabilities. [0003] The optical three-dimensional measurement system based on surfa...

AI Technical Summary

Problems solved by technology

However, there is currently no corresponding measurement method for this error, resulting in a bottleneck in the application process of the optical three-dimensional measurement system.

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