基于Hough变换和清零法的缸套内面网纹角检测

目的 发动机缸套内面网纹角直接影响到发动机的性能，为了高效准确地检测出内纹角，舍弃残次品，拟研究网纹夹角的检测方法。方法 采用邻域运算和自适应中值滤波对网纹图像进行图像增强，达到去除噪声和保留细节的双重效果；然后对其进行边缘分割处理，得到边界分明的边缘图像；再对其进行二值化，以减少Hough变化所用时间；最后提出一种基于Hough变换与清零法相结合的直线提取算法，并根据提取的直线特征计算网纹角。结果 实验结果表明，基于所提算法检测出来的夹角，对比传统方法和国外通用的仪器，平均检测误差降低为0.43%。结论 所提算法具有夹角误差小、准确度高、用时少等优点，能代替昂贵的进口仪器。所提算法在直线检测和包装条形码领域有较好的应用价值。

Detection of Crosshatch-angles for Cylinder Bore Based on Hough Transform and Zeroing Method

The work aims to study the detection method of crosshatch-angle to detect the internal crosshatch-angle efficiently and accurately and discard defective products, as the internal crosshatch-angle of engine cylinder bore directly affects the performance of the engine. Neighborhood operation and adaptive median filtering were adopted to enhance the crosshatch image, so as to achieve the dual effects of removing noise and preserving details. Then, the edge segmentation of the image was carried out to obtain the well-defined edge image and then the image was binarized to reduce Hough change time. Finally, a line extraction algorithm based on Hough transform and zeroing method was proposed, and the crosshatch-angle was calculated according to the extracted line features. The experimental results showed that, based on the angle detected by the proposed algorithm, the average detection error was reduced to 0.43%, compared with the traditional method and overseas universal instruments. Featured by small angle error, high accuracy and less time consumption, the proposed algorithm can replace expensive imported instruments, and it has better application value in the field of line detection and packaging barcode.