A Novel Method for Space Circular Target Detection in Machine Vision

Abstract

Computer-vision-based space circular target detection has a wide range of applications in visual measurement, object detection, and other fields. The space circular target is projected into an ellipse in the camera for localization. Traditional methods based on monocular vision use a precise calculation model to calculate the center coordinate and normal vector of the space circular target according to the image’s elliptic parameters. However, this accurate calculation method has the disadvantage of poor anti-interference ability in practical application. Aiming at the shortcomings of the above traditional calculation method, this paper proposes an optimization method for fitting the circular target in 3D space, where the image ellipse is projected back into 3D space and then detects the center coordinate and normal vector of the space circular target. Unlike the traditional method, this approach is not sensitive to the image’s elliptic parameters; it has stronger noise resistance performance and notable application value. The feasibility and effectiveness of the proposed method were verified by both simulation and practical experimental results.

An accurate novel circular hole inspection method for sheet metal parts using edge-guided robust multi-view stereo

“…For sheet metal parts, this need is even more prominent because the feature holes on a surface serve as references for the installation and positioning of other parts. Traditionally, as the most common feature in the industry [4][5][6], measurements of circular holes are usually performed by skilled workers using a gauge or a caliper, or by a coordinate measuring machine (CMM) with high precision. However, this inevitably leads to problems that include high labor intensity, low efficiency, and high costs.…”