Calibration method of linear scanning mechanism for cylindrical visual target

Abstract

The invention provides a calibration method of a linear scanning mechanism for a cylindrical visual target, which is characterized in that a calibration column is adopted to calibrate the linear scanning mechanism, and a first calibration line, a plurality of second calibration lines perpendicular to the first calibration line and a calibration circle are marked on the cylindrical surface of the calibration column; the method comprises the following steps: firstly, an image acquisition height is set based on a first calibration line graph displayed in an image acquired by a line scanning camera; the first calibration line graph and the projection of the acquisition line of the line scanning camera on the plane of the camera chip form an included angle; the vertical included angle between the acquired first calibration line graph and the projection of the acquisition line on the plane of the camera chip and the multiple of the long axis and the short axis of a calibration circle graph corresponding to a calibration circle of the calibration column are solved according to the pixel position difference of the distance between the second calibration line graph and the pixel position difference; the angle, the included angle and the rotating speed of the bearing platform are sequentially adjusted through the angle and inclination angle adjusting mechanism and the rotating driving mechanism, and calibration is completed.

Description

technical field [0001] The invention belongs to the field of machine vision and relates to a calibration method for a line-scanning mechanism aimed at a cylindrical visual target. Background technique [0002] The line scan camera can capture high-resolution images of objects moving at a constant speed, and is suitable for high-speed or high-resolution image collection. It is also suitable for high-precision detection of curved surfaces such as bearings in industry and flower print detection and measurement of cylindrical product surfaces. [0003] Due to reasons such as mechanical installation, it is difficult for the line scan camera to be parallel to the cylindrical surface of the workpiece to be measured, resulting in the deformation of the collected image, and finally it is difficult to obtain pictures that can be used for measurement or defect detection. The existing method is to ensure that the line-scanning camera is parallel to the measuring cylinder through mechani...

AI Technical Summary

Problems solved by technology

[0003] Due to mechanical installation and other reasons, it is difficult for the line scan camera to be parallel to the cylindrical surface of the workpiece to be measured, resulting in the deformation of the collected image, and finally it is difficult to obtain pictures that can be used for measurement or defect detection

The existing method is to ensure that the line-scanning camera is parallel to the measuring cylinder through mechanical limit and other means, and set an appropriate speed to obtain an image without deformation. The cost is difficult to control; the second is that the installation requirements are very high, and a small part that is not installed in parallel may cause the line scan camera to fail to work normally; Multiple acquisitions and multiple adjustments, time-consuming, low efficiency and no guarantee of accuracy

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