Study Of Involute Micron Gear Measurement On Machine Vision

Micron gears are widely used in many precision optical instruments, aeronautical and radio instruments, whose precision directly affect the operating performance and the service life of instruments. Micron gears are so small that we can not measure them accurately and efficiently on traditional gear measurement instruments with traditional method. The method should be renovated urgently.According to the feature of involute micron gear, a measuring system of involute straight spur gear is designed based on machine vision and digital image processing after considering the precision, efficiency and cost. The measuring platform of the system is based on the universal tool maker's microscope. The CCD camera, image acquiring board and computer are employed to acquire the image of the gear. The image pretreating, edge detecting, edge fitting and image measuring can be done with the software that we program with LabVIEW and IMAQ Vision. Finally, the result of the measurement is transformed from pixel value to real value by system calibration. The system software is programed with LabVIEW7.0 and IMAQ Vision which are all popular machine vision tools as the software platform. And it is designed by modular, so it has excellent reliability, maintainability and expansibility.The machine vision system has the capacity of measuring the geometric parameters and the simple errors of involutes straight spur gear, including single pitch error, total cumulative pitch error, total pitch error and tooth profile error. Comparing with the universal tool maker's microscope method and machine vision method, the machine vision method is proved practically. And it has the advantage of high efficiency and less personal errors.