Research On Panorama Image Capture System Of High Speed Moving Cable Surface Inspection

Cable industry is one of the most important national infrastructure industries. So far, the cable surface inspection in China is mainly through the manual inspection. The manual inspection is low efficiency and high false inspection rate. In recent years, the technology of machine vision is developed fast. It is noncontact method. The foreign machine vision technology is more mature, and the research on machine vision technology is started late in China. The machine vision technology has not been applied in the surface inspection of cable. Research on the system of cable surface inspection based on machine vision technology is very significance.Image capture and image processing are the most important parts of machine vision system. The quality of image affects the system of image processing directly. In my dissertation, the cable panoramic image acquisition system based on Zynq has been designed. The main research content is divided into three parts.Firstly, the optical system of the cable panoramic image acquisition has been designed. In order to realize the cable panorama image acquisition, the optical platform based on plane mirror system has been designed. According to the demand of image processing system and the moving speed of cable, the appropriate camera and lens have been selected. The results of experimental show that, the optical system can capture the panoramic image of cable of 6.53 mm diameter, and the resolution of image is 22.5 ?m.Secondly, the circuit of image acquisition and transmission has been designed. In order to solve the problem of the high-speed LVDS differential transmission line impedance matching, timing, and the high speed signal crosstalk and so on, the technologies of snake wiring, impedance control, and signal isolation have been applied. The sub card of Camera Link to FMC has been designed.The serial Camera Link image data is deseriallized by this card. Then the image data is input to Zynq int by FMC interface.Finally, the FPGA logic circuit in Zynq has been designed. In order to realize the acquisition, caching, preprocessing and display of high-speed Camera Link image data, the technologies of parallel processing, pipeline, pingpong operation, synchronous circuit design, AXI bus interconnect and so on have been applied. The module of camera trigger, image capture, image preprocessing, HDMI display driver and so on have been designed. The results of experimental show that, the system can capture the image,which is 50 fps, 1600×1200 resolution and 8 bits gray image, and output HDMI high resolution image, display on the displayer.The system has been tested on the experimental platform?Experimental results and theoretical analysis show that,the system can capture the image of moving cable, the moving speed of cable is 1 m/s, and the diameter of cable is 6.53 mm. The images are clear and small distortion. The image can meet the demands of industrial testing. To our knowledge, the method of capture panoramic image of the moving cable, which is implemented by single camera and optical platform, is the first report in China.