Calibration method of multi-camera visual inspection device

Abstract

The invention discloses a calibration method of a multi-camera visual inspection device, which comprises the following steps: placing a calibration plate below the inspection device, the calibration plate comprising a common sign circle and a characteristic sign circle, and the size of the characteristic sign circle being obviously different from that of the common sign circle; a common mark circle closest to the characteristic mark circle being a mark circle; the detection device shooting the calibration board, selecting a calibration board image shot by any camera and records the calibrationboard image as a to-be-processed image, performing image processing on the to-be-processed image, and obtaining contour information of a common sign circle and a characteristic sign circle in the to-be-processed image; performing ellipse fitting on the contour information, and making a straight line lAB; performing ellipse fitting on the circle center coordinates of the plurality of common mark circles again to obtain a point O1; making a straight line lo through the point O1, marking an intersection point of the straight line lAB and the straight line lo as O2, and obtaining a pixel coordinate O3 of the center of the detection equipment. According to the method, the pixel coordinates and the image pixel equivalent of the center of the detection equipment can be accurately obtained.

Description

technical field [0001] The invention relates to the field of camera calibration, in particular to a calibration method for multi-camera visual inspection equipment. Background technique [0002] In order to meet the measurement field of view and measurement accuracy requirements, the visual sensor often needs to install multiple cameras, such as the car glue detection sensor, which adopts the method of nesting multiple cameras on the nozzle of the glue gun, and the multi-camera acquires the glue strip image at different positions , to realize the 360° range detection of the rubber strip. At present, the existing calibration method is mainly aimed at the calibration of a single camera or a dual camera. Since it is difficult for multiple cameras to capture the calibration plane at the same time, the position of the camera cannot be determined during the calibration process, resulting in the calibration of multiple cameras. The calculation is complex and time-consuming, and the...

AI Technical Summary

Problems solved by technology

[0002] In order to meet the measurement field of view and measurement accuracy requirements, the visual sensor often needs to install multiple cameras, such as the car glue detection sensor, which adopts the method of nesting multiple cameras on the nozzle of the glue gun, and the multi-camera acquires the glue strip image at different positions , to realize the 360° range detection of the rubber strip. At present, the existing calibration method is mainly aimed at the calibration of a single camera or a dual camera. Since it is difficult for multiple cameras to capture the calibration plane at the same time, the position of the camera cannot be determined during the calibration process, resulting in the calibration of multiple cameras. The calculation is complex, time-consuming, and the calibration work cannot be completed at one time

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