Automatic Verification System Of The Pointer Instrument Based On Digital Image Processing Technology

In this dissertation, an auto-detecting method of detecting analog measuring instruments, based on digital image processing technique, high-precision grating measuring technique and step-electromotor controlling technique, is put forwarded. When the digital image processing technique is applied in the precision detecting of the analog measuring instruments, it has advantages of high precision detecting, high efficiency processing and auto-detecting.In this system, the movement of the step-electromotor is controlled by computer, and then the dial pointer is drove by the step-electromotor. At the same time, these images of the analog instrument are took by high precision CCD video, and then these images will be processed by the computer, using some image-processing algorithms such as image segmentations, threshold identification, image binarization, areas labeling, dial center-point identification, useful areas identification & abstracting, and areas thinning, etc. Followed this, the dial pointer of the"circle"is able to be located. At last, the dial pointer position will be recognized by the computer. In accordance with the nation criterion of analog measuring instruments, the precision data of the analog measuring instrument will be worked out, and these data will be used to identify the quality levels of the analog measuring instrument. Finally, the report form of this detection results will be printed. The study on the auto-detecting system of analog measuring instruments presents several optimum algorithms to realize the quick recognition of the dial pointer and calibration lines of detected dial. By using these efficiency algorithms, both the accuracy and the real-time quality have been improved.The micro displacement servo system includes the step-electromotor, step-electromotor driver, grating displacement sensor and gearing, etc. The controlling system runs in the platform of WINDOWS, and the complement of the software model is coded by Visual C++ 6.0. Moreover, the person-computer alternation interface is friendly.This auto-detecting system can detect the precision of the analog measuring instruments by using digital image processing techniques, which can advantage its work...