Tool safety is an important part of machining and machine tool safety, and machine tool path image detection can effectively obtain the in-machine condition of a tool. To obtain an accurate image edge and improve image processing accuracy, a novel subpixel edge detection method is proposed in this study. The precontour is segmented by binarization, the second derivative in the neighborhood of the demand point is calculated, and the obtained value is sampled according to the specified rules for curve fitting. The point whose curve ordinate is 0 is the subpixel position. The experiment proves that an improved subpixel edge can be obtained. Results show that the proposed method can extract a satisfactory subpixel contour, which is more accurate and reliable than the edge results obtained by several current pixel-level operators, such as the Canny operator, and can be used in edge detection with high-accuracy requirements, such as the contour detection of online tools.

中文翻译：

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定点刀具路径测量的亚像素算法研究

刀具安全是加工和机床安全的重要组成部分，机床路径图像检测可以有效获取刀具的在机状态。为了获得准确的图像边缘并提高图像处理精度，本研究提出了一种新的亚像素边缘检测方法。通过二值化对预轮廓进行分割，计算需求点邻域内的二阶导数，并按照规定的规则采样得到的值进行曲线拟合。曲线纵坐标为0的点为亚像素位置。实验证明可以获得改进的亚像素边缘。结果表明，该方法能够提取出令人满意的亚像素轮廓，比目前几种像素级算子得到的边缘结果更加准确可靠，