一种快速检测光滑半球表面缺陷的方法

针对具有镜面反射特性的光滑球面,提出了一种利用反光带的镜像变形来对表面缺陷进行快速检测的新方法。这种方法通过漫反射反光带增强图像上的缺陷信息,克服了背景噪声在图像处理中会造成较大误差的缺点,也降低了照明系统的设计难度。根据缺陷引起的反光带镜像变形获取缺陷特征,使图像处理软件的工作量大大减少。通过实验,给出了缺陷尺寸和扫描间隔等因素对检测结果影响的分布曲线,为合理提取缺陷尺寸提供了参考。实验表明,该方法的鲁棒性好、效率高,能识别0.5mm以上的全部缺陷,定位误差在 1之内。

A fast defect-detecting method for smooth hemispherical shell surface

To detect defects on smooth hemispherical shell surface with specular reflection, a novel fast method according to distortion image of reflection strip is proposed. The contrast of defect information on image is enhanced by diffuse reflection strip, a larger error caused by background noise during image processing is overcome and the design difficulty of illumination system is reduced. The reflection strip images distorted due to surface defect are useful for efficiently extracting defect feature. It could greatly reduce programming task of image processing software. Effect distribution curves of scanning interval and defect sizes on detecting results are obtained by experiment, and it can supply references to detect defect sizes reasonably. The experiments show that the method is robust and effective. It can identify defects more than 0.5mm and its positioning error is within 1?on the hemispherical surface.