Bullet primer assembly depth line structured light measurement method

Abstract

The invention provides a bullet primer assembly depth line structured light measurement method. The bullet primer assembly depth line structured light measurement method comprises a measurement modelfor bullet primer assembly depth, a calibration method and a laser speckle light bar center extraction method. In the measurement model, under a camera coordinate system, two calibration blocks are introduced to calibrate structured light parameters, and straight line fitting is carried out on a plurality of special points on the calibration blocks. The intersection point of the straight line andthe laser curve is calculated in a camera coordinate system. A laser plane calculation formula is obtained according to the principle of cross ratio invariance, and the calibration process of the structured light parameters is completed. Through a new mathematical model, world coordinate values corresponding to two points on any laser line on an image can be calculated, a real-time calibration andmeasurement mode is adopted, the real-time measurement requirement of bullet primer assembly depth measurement is met, and accumulated errors are reduced. And image enhancement operation is performedon the speckle part in the image according to the high-frequency gain coefficient so that the problem of gun and bullet primer depth measurement precision and stability reduction caused by laser strip speckle can be solved.

Description

technical field [0001] The invention relates to the field of industrial vision detection and measurement, and in particular to key technologies such as construction and calibration of a structured light measurement model, extraction of centerline structured light centers in images, and the like. Background technique [0002] In the process of bullet production and assembly, if the primer assembly depth is not up to standard, it will have a serious impact on the quality of the bullet. The effective detection area of ​​the bullet primer is less than 100mm 2 , the depth detection accuracy standard is required to be less than 0.02mm. Most domestic bomb factories still use the traditional contact mold detection method, which requires a lot of manual cooperation and is efficient and low cost. The detection accuracy depends on the dimensional accuracy of the mold. As time goes by, the size of the mold changes, and the detection accuracy decreases. In recent years, in the field of...

AI Technical Summary

Problems solved by technology

When the laser bar is projected onto the bottom of the bullet under the same lighting conditions, there will be alternating light bars and speckles in the camera imaging. The traditional method cannot extract the center of the light bar with high precision, which affects the accuracy and stability of the bullet’s primer depth measurement.

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