摘要
针对玻璃管温度计的结构特点,结合检定温度计的实际工作环境研制了玻璃管温度计示值视觉检测系统。该系统根据温度计在图像中的横向特点,运用灰度极小值法、水平投影法,找到并提取出温度计图像,根据刻度线的垂直特性,运用模板二值化法对温度计图像加以处理并对处理后的刻度线图像进行细化并分析得出刻度线的位置。通过hough变换,将膨胀算法和腐蚀算法相结合得出液柱头的位置,再通过投影分析得到温度计上的数字字符和字符对应长刻度线的位置,最终得出正确的示值。通过实验证明该系统稳定、可靠,识别精度可达0.01℃以上。
Aiming at the structure characteristics of glass thermometer and considering the actual working conditions of verification thermometer,a visual inspection system for the glass thermometer indication was developed. The system has transverse characteristics of the thermometer in images based and both gray minimum value method and horizontal projection method adopted to find and extract thermometer images and then has the characteristics of vertical scale line based and the template binarization employed to process and refine thermometer images so as to get scale line position. Through the hough transform and combining expansion algorithm with corrosion algorithm,the liquid column's position can be reached; and through the projection analysis,the digital characters on the thermometer and that corresponding to the long scale line position can be obtained,including the correct thermometer indication. The experimental result proves the system's stability,high reliability and recognition accuracy up to more than 0. 01 ℃.
出处
《化工自动化及仪表》
CAS
2016年第1期32-36,107,共6页
Control and Instruments in Chemical Industry
