针对无坡口平板对接焊缝，研究一种应用线结构光传感的角点检测原理实现焊缝特征检测与跟踪的方法.与基于线结构光形变特征检测焊缝位置的传统方法不同，根据激光条纹在焊缝处的灰度变化，运用图像形态学处理方法，提取焊缝中心特征.计算图像每列邻域内灰度值和，运用中心差分方法，提取焊缝图像感兴趣区域.再依据角点检测原理，确定焊缝中心亚像素级坐标位置，通过简单快速的系统标定，得到焊缝实际位置偏差.结果表明，对焊缝间隙为0.2 mm左右的对接焊缝进行跟踪试验，平均误差均保持在0.1 mm以内，满足焊缝跟踪精度要求.
A method for detecting and tracking the non-groove butt joint by using the principle of corner detection based on line structured light vision sensing is studied. It is different from the traditional line structured light sensing method to detect the weld position according to the deformation feature. The proposed method applies for the fact that the laser stripe has obvious gray gradient variation in the weld. The morphological image processing method is adopted to extract the feature of weld center. The gray value of each column in the image is calculated, and the region of interest is extracted by the central difference method. According to the principle of the corner detection method, the sub-pixel coordinates of the weld center can be determined accurately. The actual position deviation of the weld is obtained by using a simple and fast system calibration. Experimental results show that the average error can be kept within 0.1 mm by tracking a butt joint whose width is about 0.2 mm, which can meet the requirement of seam tracking precision.
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