基于Hough变换的焊缝位置检测技术

METHOD OF DETECTING WELDING SEAM BASED ON THE HOUGH TRANSFORM

对Hough变换的应用技术进行了细致的分析,归纳出了图像域参数与变换域参数的三种对应关系,减少了Hough变换运行时一些盲目的搜索和计算,提高了算法的运行效率。在累加器设计上,应用了三元组数据结构, 压缩了累计器的数量。应用Prewin边缘检测方法和中值滤波技术将图像转换为二值图像,使边缘部分得以增强, 噪声得到抑制。在此基础上,提出了一种新的焊缝位置检测方法,该方法不仅能检测出焊缝的偏离距离,而且能检测出焊缝偏离的方向。仿真与实际运行结果表明该方法检测精度高,抗干扰能力强。

A comprehensive analysis on the Hough transform for detection of straight line in an image is presented. Firstly, the corresponding three relations between the parameters of straight line in an image field and in the transform field were summed up. By those, the aimless computations and searches in Hough transform processing can be reduced greatly and its efficiency is improved. Secondly, in the design of accumulator, a triplet data structure is used and can reduce much amount of accumulator. Thirdly, a new detection method of welding seam is proposed based on these results, by the method, the offset of welding seam is not only detected, but its direction is also obtained. In the implementation of the method, the objective gray image is transformed black-and-white image with the edge detection of Prewitt and median filtering algorithm, therefore the welding seam is enhanced and that the noisy is depressed. Finally, simulating and practical application results show that the detection precision of the method is higher and the anti-interference ability is good.