The Application And Research Of The Visual Inspection In Surface-mount Technology

Visual detection technology is a technology,which is applied to detection of machine vision technology in the field of a technique. Because it has a non-contact, high-speed, highprecision advantage,in today's industrial automation trend of rapid development, visual detection technology has become increasingly common used in various production sectors, It has driven the entire industrial automation production rapid development of the industry. This paper focused on the research and application of the visual detection system mount technology.The module of the visual inspection mainly does the following work:positioning PCB board Including machine X, Y, Z each control axis, ball screws and other motion control hardware;upper-layer software,namely man-machine interface, including visual inspection systems, debugging interface, zero interface and so on. Entire placement process complete accurate placement through co-operation with the two most common elements.This aimed at obtained some datas to operate faster and more by visual detection technology, then transmissed that data to the next crew to complete the placement.In this article, we focus on the visual detection system and application process and related theoretical methods on SMT.The hardware types and parameters involved in the visual detection system,described the principle and working process of placement placement.It describes the image smoothing,expansion corrosion,binarization,edge detection and extraction,image processing method,image recognition method introduced PCB board and component pin point Mark the center point. Visual inspection system is mainly realized:PCB board location;identification and correction component..PCB board position,mainly refers to get Mark the center point of the PCB and deflection angle of the PCB board.First, collecting the Mark image by upper camera,after ROI extraction,image preprocessing,binarization,edge detection,the paper acquired sub-pixel coordinates of the center point of the PCB Mark point by the sub-pixel interpolation by polynomial algorithm.this theory improved the PCB board positioning accuracy. Similarly Get another center point diagonally Mark subpixel coordinates.Mark points to get the machine coordinates by the coordinate conversion,the last point will be connected to the corner Mark,the calculated deflection angle PCB board.Save the data up call for the next And correction crew.The main part of the element content correction is to obtain components and elements deflection angle the center of the machine location.when paste titles driving components, the camera get element image,after image processing,we obtain the sub-pixel coordinates of element's center.through the breadth of graph search method,the most up point,the most bottom,the most left and most right four vertices,four points were extracted from the pin center,then calculating the rectangle composed of center is the center element calculated offset its distance from the axis of the patch. By extracting the center of a single row of pins, linear least squares fitting draw element deflection angle. The data obtained are saved, the next crew will be able to call the information center offset compensation and angular deflection element,thereby completing the placement. In this paper,in order to improve the speed and accuracy of placement in terms of algorithms to optimize the placement function.