Based On Image Processing Technology Parameter Measurement Of Gear

The thesis presents the image measurement method of gear parameters based on the image processing technique, mainly introduces the image measurement method of the involute error and the mathematic model of the involute error measurement through the method. Especially aimed to the small module gear with small dimension, the method can carry out on-line non-touch measurement and solve the difficult problems, which can't solve through the traditional measurement.The.task whole structure designed can be formed of three segments. Firstly, gear image sampling and gear profile image processing are expatiated in the paper. Image pretreatment, edge detection arithmetic and edge extraction arithmetic were introduced in the image processing segment. Otherwise, curve fitting arithmetic was mainly analyzed to solve the problems, which are that measurement precision is to 1 pixel and exact position can't be confirmed, and improve the measurement precision to sub-pixel. Secondly, establishing the reasonable coordinates in the whole measurement system, all coordinates were unified to the world coordinate system based on mutual conversion relations of different coordinatesand conversion relations of pixel and real dimension. Analyzed traditional measurement method and measurement process of gear involute error, image measurement method was proposed and measurement model was established. The gear profile was individually imaged by the CCD camera and processed. Applied to image joint technique, individual image was jointed to reflect the whole information of gear profile. Finally, according to the measurement definition of the gear involute error, an involute column gear with straight tooth was measured and the mostly reasons which affect the measurement results were analyzed. Gear parameter measurement and error analyses were implemented automatically and more completely through the computer.Experimental results indicate that the camera aiming replacing the naked eye aiming and automatic reading are to reduce the adjustment part for gaining corresponding information of gear generating angle in traditional measurement, increase the measurement points at the process of measurement through image method, which is useful to reflect the real involute profile. Besides, the use of image measurement method, not only the aiming error and reading error of measurement instrument but also the personnel errors are reduced. Besides, the study of image measurement system and data processing method was useful and referential for measurement of other geometric parameters.