基于图像识别的吸蓝量滴定终点自动判定新方法

快速准确测定粘土旧砂中的有效膨润土含量,是大规模粘土砂型铸造生产中正确制定粘土型砂混制配方及工艺的基础,对获得高性能的型砂具有重要作用。现有的粘土旧砂中的有效膨润土含量通常采用吸蓝量滴定方法测试,并肉眼判断滴定终点。在遵循现有膨润土吸蓝量测试原理的基础上,作者提出一种基于图像识别技术的吸蓝量滴定终点判断新方法,该方法利用不同颜色在RGB三通道中的感光程度的差别,对彩色图像进行RGB三通道分解和减法运算,计算淡蓝色晕环和内圈深蓝色斑点的面积比值,当比值达到预设值后,判断达到滴定终点。该方法利用先进的计算机图像识别系统替代人工肉眼识别,大大提高了识别及测定精度。

The New Method of Automatic Judgement for Titration End-Point of Methylene Blue Absorption Based on Image Recognition Technology

To determine the effective bentonite content of clay used sand fast and accurately is the basic for making correct mixing ratio and process in preparation of clay moulding sand,and it also plays an important role in obtaining high-performance moulding sand.The conventional method of determining the effective bentonite content is the methylene blue absorption test method,and the titration end-point is determined by naked eye.Following the traditional method principle,a new method of automatic Judgment for methylene blue absorption end-point is put forward,which is based on image recognition technology.The photosensitive degree difference of the different colors in three-channel of red,green and blue is applied in the image recognition method.First,decompose the color images into three-channel gray images,then,make gray value subtraction operation of the gray images,finally,calculate the area ratio of outer circle light blue halo and the inner circle blue spot.The titration process is judged to reach the end-point while the area ratio higher than the pre-set value.The advanced computer image recognition system substitutes for the recognition by naked eye,which greatly increases precision of recognition and determination.