A positioning method of engine cylinder block casting based on machine vision

Abstract

The invention discloses a machine vision-based engine cylinder block casting locating method. The method comprises the steps of obtaining a cylinder block image, processing the cylinder block image, identifying and locating a cylinder block, and the like. Two through holes in the middle of a cylinder block casting serve as capture targets, so that a locating error caused by camera distortion can be effectively avoided; for the relatively deep through holes of the cylinder block, strip-shaped light sources on two sides are adopted for lighting at a low angle, and a camera with the low resolution and the long focal distance is adopted to obtain an ideal initial image; for burrs and pits on the surface of the casting, a processing method suitable for the cylinder block image is proposed and comprises the steps of graying, binarization, color reversion processing, regional threshold segmentation, opening-closing operation and regional filling, an ideal image segmentation effect is achieved, and the through holes are smooth and non-sticking in edge and complete in shape; and for the specific shapes of the through holes, the circularity is taken as a judgment index, the regional centroid is taken as a locating object, and a simple locating method that meets the precision requirement is obtained.

Description

Technical field [0001] The invention belongs to the field of machine vision, and particularly relates to a method for identifying and positioning engine cylinder block castings. Background technique [0002] At present, in the post-processing processing line of castings, large castings, such as engine cylinders, often require manual loading and unloading and clamping, resulting in low efficiency and increased labor costs. Machine vision technology can improve the degree of automation of the production line, and can be used in workpiece loading and unloading, defect detection and visual measurement. It can not only reduce labor costs, but also replace humans in complex and dangerous industrial environments. The method of identifying and positioning the target workpiece varies with the change of the workpiece. [0003] Due to the large volume of the engine cylinder, the rough surface of the castings, the shadows of the acquired images, and the serious deformation of the through-hole...

AI Technical Summary

Problems solved by technology

[0004] Aiming at the problems of large volume of casting cylinder, rough surface of casting, many shadows in acquired images, serious deformation of through holes, etc., the present invention uses the middle two through holes of cylinder casting as grabbing targets, and provides a method for large cylinder castings. A set of methods for identification and positioning, including acquisition of casting images, image preprocessing, image feature extraction, identification of regions of interest and positioning of regions of interest, serving the subsequent robot automatic loading and unloading system

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