Research On Inspection Technology Of Needle Plate Hole Size Of Needle Punching Machine Based On Machine Vision

Needle plate is one of the most important parts of needling machine producing non-woven fabric by reinforcing method.In recent years,the production of needle punched nonwovens is increasing,and the demand for quality is increasing.Whether the performance of a needle punching machine is good determines the quality of needle punched nonwovens.The quality of acupuncture products depends on the perfect fit of the needle with the needle plate,so the measurement of the pore size of the needle plate is an important step in the production of the needling machine.This topic comes from the key scientific research projects of Henan University and the open laboratory of open laboratory in key disciplines of modern manufacturing equipment and instruments in Henan province.In view of the development of small teaching needling machine,a needle plate based on machine vision technology is put forward on the basis of the current research and analysis of the needle plate testing.Dynamic testing technology.The length and width of the needle plate of the needle punching machine is 288mm* 148 mm,and the needle plate has 684 holes with a diameter of 1.83 mm.According to investigation,in actual production,needle plate is checked by standard stopper or manual inspection.This testing method takes a long time and low accuracy,and it is hard to meet the increasingly progressive industrial production demand of nonwovens industry.In view of the production demand of this line,a method of measuring the size of needle plate in acupuncture machine based on computer vision is studied.It is of great significance to detect the size of needle plate hole position of acupuncture machine through camera shooting and image processing technology.On the basis of the development of machine vision at home and abroad and the application of machine vision technology in the field of textile,this paper puts forward the design idea of machine vision technology to detect needle plate of acupuncture machine.First,aiming at the actual inspection demand of needle plate size of needle punching machine,a reasonable detection process is designed.Through determining the camera and lens and lighting way needed in the detection system,we set up the measurement platform for the machine vision inspection needle plate.Secondly,Halcon is selected as image processing software to process the needle plate image and extract the target feature.Median filter and Laplasse sharpening of the collected images were done through histogram threshold segmentation and Roberts operator edge detection.The target feature is finally extracted.Then,the calibration of the calibration board is carried out by using Halcon software,and the lens distortion can be eliminated.Then the center coordinates and diameter of the needle plate hole position are calculated by the Area_center operator of Halcon software,and the size of the needle plate is realized by using the calibration parameters to realize the machine vision inspection of the needle plate size.Finally,the stability of the experimental platform is verified through repeated experiments.By using the high precision imager of the laboratory,the hole position of the needle plate is detected,and the experimental design scheme is verified by comparing the experimental results of the two detection methods.The results show that the testing scheme of needle plate machine vision hole position in acupuncture machine is feasible.It can ensure the precision of needle plate detection and shorten the production cycle of needle plate.It has great practical value.