| With the rapid development of science and technology,machine vision technology has a lot of advantages in the field of industrial screening,the research and application of visual technology has become increasingly popular in recent years.In this thesis,we mainly study the surface defects and size of the rivets.The traditional detection method adopts artificial visual inspection,which is extremely inefficient,it is also difficult to meet the requirements of high precision.In order to replace artificial and improve efficiency,the automatic detection technology of rivet becomes increasingly important.Thus,an automatic rivet system based on machine vision is proposed.This thesis first introduces the principle of image acquisition system and carries on the detailed in-depth introduction from the image algorithm design and software system design to system joint debug.The entire specific work content and result are as follows:1.In terms of acquisition system,the key equipment is purchased based on the actual demand.Four pictures are transmitted to the computer by different light-transmitting modes;2.In terms of image algorithm,it is overcomed that the interference factors such as external complex environment during the study of different detection algorithms of rivet.The OpenCV library is used to carry on the secondary development and achieve the requirements of the precision,such as image denoising,segmentation,morphology,feature extraction and etc;3.In the software development of the upper computer,the Microsoft Base Class Library is used to ensure the stability and efficiency of equipment operation.In the aspect of joint debugging,the reasonable and stable communication protocol can guarantee the correctness of data transmission.In addition,it can also respond to the faults which may appear in the detection process.So far,the entire iterative software development version is more than 70 times and the system has experienced joint debug for a few months.In March,2018,the acceptance of the expert panel was approved.The system successfully implemented the detection accuracy in the range of 0.005 mm and the judgment of the defect could reach 0.3mm as well as the detection speed reached 50 pieces/min.Automatic high precision screening system makes the high efficiency detection of aviation rivets possible,which has a great practical value.By updating the algorithm,it also can be applied to the detection of other connectors,such as screws,drills. |
