Research On High-precision Visual Measurement System Of Micro Electronic Connectors

Owing to the large-scale usage and wide distribution, micro electronic connectors are the essential components to realize the separable electric contact. Therefore, its reliability is the key to normal operation of the whole electronic equipments. Nowadays it is more difficult to realize the high-precision detection on micro electronic connectors as high reliability, miniaturization and precision are required. Meanwhile, some domestic enterprises occupied in visual inspection have made equipments aiming at appearance inspection of electronic connectors. However, these equipments, which are restricted to size type, detection efficiency, measurement accuracy and the cost, can not be applied to various types of online inspection on electronic connectors. This paper proposes a new high-precision visual measurement system of micro electronic connectors, which aims at problems during online inspection. The system can realize the high speed and precision online inspection on various types of connectors.The whole components of measurement system and operating principle, ranging from mechanical structure, motion control to optical, which are used to design the hardware platform, are summarized in the aspect of hardware structure design. In order to ensure the distinguishability of image collection and improve the degree of inspection automation, sectional measurement is applied to high-precision visual measurement system of micro electronic connectors, two array CCD cameras are used to get images synchronously. Driven by PLC, the subdivided workbench is real-time controlled and segment fed, and keeps high precision. Thus the automation of image acquisition and detection is realized.In the aspect of software algorithm design, high precision demarcate gauge blocks are used to the calibration of image measurement system. Allowing for the regular shape of the pin and the noises produced during image acquisition, average filter is selected to smooth the image, then divide the image into sections with unique properties, we choose sections interesting from them. During one direction’s movement of the precise slide, images of connector that segment acquired are finally stitched before measurement, numbering the pins and measuring central coordinates of pins. On the basis of matching algorithm of feature points, we get the mosaic image via registering and fusing single image in turn. Measuring the mosaic image by visual system, from which the results are acquired. The accuracy and precision are verified by comparing this results with the connectors’ measurement results acquired from image instruments.Speed control of stepper motor, communication control of PLC, real-time display of interface, real-time processing of massive images, record of database, executing of eliminating mechanism, all above are involved in the research of this measurement system. All detached equipments, function and information are gathered in a system that unified, correlative and coordinated, which make the resources fully shared and high efficiently operating. The final experimental data suggest that the research realize the high precision and efficiency defecting on connectors, which satisfy the requirement of enterprise...