Research On Key Technology Of Machine Vision For Visual Laminating System Of Electroacoustic Device And PCB

In recent years,with the continuous advancement of the "Made in China 2025" strategy,and the rapid popularization of smart electronic products such as smart phones and tablet PCs,the electro-acoustic device industry has entered a stage of rapid development.Electroacoustic device industry is a processing and manufacturing industry integrating printing,dispensing,laminating,welding and assembly.Laminating is a key step,and its effect directly affects the quality of the processed products.In this paper,combined with the actual situation of the electro-acoustic device and PCB laminating process,focuses on the key technology of machine vision for visual assembly system of electroacoustic device and PCB.Developed a visual laminating system with high automation level,strong environmental adaptability,convenient operation and good stability.The main contents of the paper are as follows:(1)Based on the laminating process and application requirements,the hardware system design of the visual laminating system is completed,including the hardware selection of the machine vision system,the image acquisition platform design and the key equipment selection,scheme layout design of the robot control system.(2)The paper researches the accurate extraction algorithm of circular calibration points.The extraction algorithm solves the problems of gray unevenness,noise and stain interference in the image extraction process by integrating image processing methods such as image preprocessing,threshold segmentation,morphological operation,edge extraction and least square method for circle fitting,improved the accuracy of circular calibration point extraction.(3)Analyzed the camera calibration technology for the visual laminating system.The traditional camera calibration mostly adopts the single-area calibration method,and the accuracy of image correction is low.The paper combines the practical application environment of the visual laminating system to propose a sub-region calibration method with higher calibration accuracy.(4)The image matching method was deeply studied for the visual fit system.Through the experimental comparison,the template matching algorithm suitable for the visual fit system is selected.Under the premise of ensuring the matching precision,three directions of optimizing the matching speed are proposed.The edge characteristics of the outer contour of the PCB board are good,and the inner contour edge characteristics are poor.So,propose a double template matching positioning algorithm.In order to improve the operation efficiency,an online template aligning method integrating template creation and mechanicalcompensation adjustment is designed.(5)According to the design principles and functional requirements,the module division and software framework of the system are determined,,and build the human-machine interface of the system.In view of the self-protection considerations during the operation of the equipment,a limit protection mechanism for the visual fit system is established.Last,verify accuracy,efficiency and stability of the entire system by experiments.