基于机器视觉的低对比度物体尺寸测量研究

工业零件的产品检测是保证零件质量合格最重要的环节.传统的接触式检测方法难以满足工业现场高效、高精度等需求,基于机器视觉的图像测量系统已广泛应用于检测产品的几何参数.非透明物体形成的高对比度图像的测量已经进行了大量的工作,针对透明物体形成的低对比度图像的研究相对较少.以直角棱镜为对象,开发了一种用于测量低对比度产品尺寸的...

Research on low-contrast object size measurement based on machine vision

Product inspection of industrial parts is the most important link to ensure that the quality of the parts is qualified.The traditional contact detection method is difficult to meet the requirements of high efficiency and high precision in the industrial field.The image measurement system based on machine vision has been widely used to detect the geometric parameters of the product.A lot of work has been done on the measurement of high-contrast images formed by non-transparent objects,and relatively little researches have been done on low-contrast images formed by transparent objects.Right-angle prisms were used as the object,and an image measurement system for measuring the size of low-contrast products was developed.First,the images collected under different light intensities are averaged to obtain a smooth image.Then the contrast-limited histogram equalization algorithm is used to enhance the contrast of the image and the Zernike moment edge detection algorithm is used to determine the precise sub-pixel edge.Several comparative experiments have verified the rationality and superiority of the improved algorithm.The average error of prism thickness is less than 0.003 mm,and the standard deviation is less than 0.0015 mm.The solution proposed provides a feasible solution for the high-precision measurement of relatively transparent objects.