Abstract:

In order to realize the automatic optical inspection(AOI)of the dimensions and defects of mini.drill blades,an automatic image inspection system is proposed and the corresponding image processing algorithms are in-vestigated.In the investigation,a special lighting system is first designed based on the characteristics of mini-drill blades to obtain clear blade images with little distortion.Next,the improved Small Univalue Segment Assimilating Nucleus edge extraction algorithm is adopted to extract the image edge.Then,the extracted edge is located by the subpixel edge location algorithm based on the spatial moments to obtain a precise Subpixel location.Finally,the algo-rithms,such as the line fitting and the circle fitting,are adopted to calculate the dimensions and to inspect the de-fects of the mini-drill blades.Experimental results demonstrate that the proposed AOI method is of an inspection ac-curacy of 99.5% and a dimension precision in the scale of micron.so it can meet the requirements of dimension measurement and defect inspection of mini-drill blades.

Key words: computer vision, automatic optical inspection, edge detection, subpixel, Small Univalue Segment As-similating Nucleus Aalgorithm