Double ccd scanning imaging detection method for surface defects of continuous casting slab

Abstract

The invention discloses a dual-CCD (Charge Coupled Device) scanning imaging detection method for continuous casting slab surface defects. The dual-CCD scanning imaging detection method comprises the following steps: (1) mounting a linear array CCD camera, an area array CCD camera and a linear laser transmitter on a continuous casting slab; (2) scanning by the linear array CCD camera and the area array CCD camera according to a synchronous frame frequency and line frequency manner to obtain a two-dimensional image and a three-dimensional image of the surface of the continuous casting slab; (3) registering the acquired two-dimensional image and three-dimensional image; and (4) carrying out information fusion processing on the registered two-dimensional image and three-dimensional image in one area on the surface of the continuous casting slab, analyzing area-of-interest features of the two images, and extracting a final area-of-interest to be identified on the surface of the continuous casting slab by combining the feature fusion processing result of the two images, thus reserving reliable defect information of the surface of the casting slab and detecting the surface defects of the continuous casting slab. According to the dual-CCD scanning imaging detection method provided by the invention, the structure is simple and convenient; the method is high in detection precision, great in real-time property and capable of automatically eliminating interference information.

Description

technical field [0001] The invention relates to continuous casting slab defect detection technology, specifically a double CCD scanning imaging detection method for continuous casting slab surface defects. The invention relates to a surface imaging and defect detection system for hot-rolled strip steel and pickled steel strip, belonging to the technical field of iron and steel metallurgy. Background technique [0002] In the field of iron and steel metallurgy, high-temperature continuous casting slab hot delivery and hot charging and continuous casting-rolling, as a continuous production technology, provide a guarantee for enterprises to improve productivity, save energy and reduce consumption, and maintain modern market competitiveness. This technology has largely shortened the complex production process of iron and steel technology, and its economic benefits are obvious. With the rapid development and application of continuous casting and rolling in the domestic metallurg...

AI Technical Summary

Problems solved by technology

Due to its strong adaptability to the environment, conventional optical detection methods have advantages in the detection of surface quality of high-temperature slabs. However, these current optical detection methods are limited by conventional CCD imaging, because the surface of slabs is often covered with scales. Due to the interference of false defect information such as iron oxide scale and vibration marks, defect images are often lost in high background noise images. Even if high-definition images are obtained, it is difficult to guarantee a reliable defect recognition rate. Therefore, the recognition algorithm design and final recognition accuracy are greatly affected. limit

The laser triangular slab surface measurement method based on the area array image sensor, due to the constraints of the spatial angle relationship, has errors in the accurate measurement of the two-dimensional shape of the defect

Similarly, the interference fringe or grating projection detection method is affected by the complex shape of the slab surface, and the phase unwrapping algorithm is difficult to design. Therefore, this method is prone to large errors in the shape extraction of two-dimensional small cracks on the slab surface

So far, domestic and foreign online detection systems for high-temperature slab surface defects still have technical weaknesses such as low detection accuracy and poor reliability to a certain extent.

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