Design Of Curved Barcode Image Acquisition Device Based On Binocular Vision

The commodity barcode is the unique identifier of the item.As a fast reading technology,it plays an important role in the logistics,settlement and storage management of commodities.Therefore,the printing quality of commodity barcodes is particularly important.In order to ensure the printing quality of commodity barcodes,the state has developed a series of commodity barcode printing quality standards.The domestic barcode inspection agencies inspect barcode quality at all levels.At present,the mainstream barcode quality inspection instrument can perform quality inspection on printed flat barcodes.However,there are many commodity barcodes in the market due to printing on curved packaging and existing detection methods cannot be detected.Therefore,this topic proposes to use binocular vision technology to detect the quality of curved EAN-13 barcodes which is used in China.The quality inspection of the binocular visual curved barcodes is divided into two parts.It includes binocular vision curved barcode image acquisition system and binocular vision curved barcode image analysis and calculation system.The main content of the image acquisition system is to image high quality and stable images with different types of curved commodity barcodes using binocular vision technology.The binocular image information is transmitted to the computer through image control transmission of the acquisition system.The image analysis and calculation system mainly uses binocular vision technology to restore the curved barcode to a flat barcode and analyze and process to obtain accurate parameters,thereby determining the quality level of the barcode.The main content of this paper is the design of binocular vision curved barcode image acquisition system,which mainly completes the following parts:First,the imaging module of the acquisition system is completed,and its main function is the image acquisition of the curved barcode by the binocular camera.Above all,after analyzing the bar code quality detection requirements,the camera and lens that meet the detection accuracy are determined.Secondly,in order to improve the accuracy of image acquisition,the triangle parameters are used to analyze the structural parameters of the binocular vision system.By analyzing the relationship between the system structure parameters and the random sampling points in the space,the system structure parameters are obtained when the image is acquired.The influence of precision,then the error function is used to determine the optimal range of binocular visual structure parameters,and the imaging module that meets the detection requirements is designed.Second,the binocular convergence control module of the acquisition system is completed,and its function is to meet the requirements of curved barcode image acquisition with different curvatures.In order to meet the barcode image acquisition requirements of different curvatures,a camera horizontal displacement control device is designed.By changing the baseline distance between cameras by horizontally driving the right camera in the binocular camera,the binocular camera convergence point is changed to achieve the collection of different curvature bar code images.The control system uses a stepping motor as the control motor,and performs serial communication through the serial communication between the STM32 MCU and the host computer.The transmission mode is screw drive,and the corresponding limit switch is designed to limit the displacement distance of the camera to meet the acquisition requirements of curved barcodes.Thirdly,the image transmission module of the acquisition system is completed,and its function is to combine the two-way binocular camera image signals into one way for transmission to the computer.Through the development of the camera built-in library file,the function of synthesizing the two-way camera signal and transmitting it to the computer at the same time and stably is completed.Fourth,the overall box structure design of the acquisition module is completed.After the structure arrangement and circuit design of each system of the acquisition module,the construction of the entire acquisition module box structure is completed,and the image acquisition of the curved barcode is completed.Finally,image acquisition and transmission of barcode for curved commodity s are carried out through the acquisition device to the computer,and quality detection of barcode for 30 curved curveds with different curvature is carried out with the help of image processing algorithm.The results show that the quality inspection of 27 curved barcodes can be completed,which proves the feasibility of the acquisition system.In the comparison test,the 100 flat bar codes that have been tested in the Shaanxi Bar Code Quality Supervision and Inspection Station are pasted on the curved package,and the test results are compared with the test station results.The results show that the test parameters are very close.The judgment results are consistent,which proves the detection accuracy of the system and effectively improves the detection technology of commodity barcodes.