Tooth Profile And Contact Spot's Two-dimensional Profile Reconstruction Of Hypoid Gear Tooth Contact Spot Image

Hypoid gear has been widely used in aviation industry, automobile industry and heavy mining equipment and so on. Because of its better property of steady work, the larger contact area, the slower of its sliding velocity and its higher transmission efficiency. In particular the automotive industry is developing rapidly so that the requirement of meshing quality of hypoid gear is increasing. One of the important indicators to measure the meshing quality is feature points of the hypoid gear surface. However, at present the detection of feature points is based on the main visual of the experienced engineering and technician. This way can no longer meet the requirement of modern production. Because this way can only assess the meshing state of the hypoid gear so that its diction accuracy will be longer and the way will also cost long time.This thesis applies the technologies of digital image processing and computer graphics to the identification process of the hypoid gear feature points proceeding from the pratical purpose. This method first process the imaging of the picked contact area of hypoid gear and extract the boundary of gear surface and feature points, which will lead the gear contour and feature points reconstructed. So the size, location, direction of feature point can be detailed evaluated in mathematical.This thesis mainly discusses the following aspects: RGB image is converted to grayscale and binary map; the disposal methods of image enhancement and image smoothing are contrasted and analyzed; choosing the appropriate option on the pre-processing of the gear contact area's image; six kinds of edge detection operator are contrasted; the boundary of image becomes continuity and smooth using the binary morphology; the curve of gear surface border is segmented fitting using the least-squares method. According to these, we can construct gear surface grid by using bilinear interpolation, and the tooth profile and feature points can be two-dimensional reconstructed in the grid coordinates.According to this thesis researching, a new way of hypoid gear contact spot online detecting is provided in improving detection of hypoid gear efficiency.