针对基王面阵CCD摄像机的热轧带钢表面缺陷检测系统所存在的问题,提出采用线阵CCD摄像机作为热轧带钢的表面图像采集装置,将激光线光源作为照明光源,解决了高温环境下的远距离均匀照明问题.采用这种图像采集方式可以使系统的精度达到0.5mm以上、针对热轧带钢表面存在的氧化铁皮、水及光照不均等问题,提出了对于不同缺陷类型建立单独的缺陷检测算法的思想.目前已经建立了纵裂与边裂的检测算法,对这两类缺陷的检出率达95%以上.
Line-scan CCD cameras were used as surface image acquisition devices for hot-rolled strips to avoid problems produced by surface inspection systems based on area-scan CCD cameras. Linear laser was used as the illumination device for homogeneous illumination from long distance under the environment of high temperature. The precision of image acquisition could be higher than 0.5 mm with line-scan CCD cameras and linear laser. A new concept of defect detection was proposed to avoid the disturbance of scales, water and un-homogeneous illumination on the surface of hot-rolled strips. Different detection algorithms were developed for different types of defects. Up to now, detection algorithms for longitudinal cracks and edge cracks were developed, and the detection rate were higher than 95 %.