Study On The Key Technology Of Billet Vision Weight Based On Linear Structure Laser

The casting billet’s cut is very important in the iron and steel production processes. At present, the continuous casting billet is mainly cut by length and supplied to steel rolling workshop. But, in the rolling procedure the standard for production’s organization is "weight". Affected by some factors such as the mold wear, temperature and so on, the cross section area will change and lead to the weight fluctuation even with the accurate length in the continuous casting process, thus the rolling yield is reduced and the cost is difficult to cut down. Therefore, changing from "cut-by-length" to "cut-by-weight" has become the key to improve the continuous casting technology, which is also the starting point and standpoint for the thesis.This thesis is an important part of the science and technology project sported by Hebei province, the technology and application of the casting billet’s weight cutting based on laser vision, project number: 13210116 D. The main research work includes the construction of the cut-by-weight system, the sensors’ calibration, the extraction of laser stripe center, the calculation of cross sectional area and the length, the software development of the weight system. In system design section, with the advantages of the line structured light 3-D vision measurement such as high precision, strong real-time, active control and so on, the measuring system of the cross sectional area and length was set up, the principle of fixed weight was proposed and the whole system was constructed. In image processing section, based on line structured light imaging characteristics in the system, stripe center’s sub pixel accuracy was obtained through image enhancement, image smoothing and curve fitting method. As for system calibration, the box shaped dot target was used to complete the calibrating experiment based on Invariance of Cross Ratio and the precision was analyzed. Then, the cross sectional area and the stripe length were obtained through Heron Formula and cross-correlation algorithm. Finally, in order to realize the automation, visualization and intelligent measurement, the software of the casting billet weight system was developed and designed use MATLAB.In general, the line structured light 3-D vision measurement technology was applied to the casting billet weight system, and the cut-by-weight method through real-time accumulation of billet weight was proposed, which would lay a theoretical and experimental foundation for the way of cut-by-weight.