A Rotation Angle Calculation Method about Bearing Images Based on Edge Image Correlations

Abstract

In Industrial automation field rotation angle calculation between successive bearing images is frequently required and the rotation angle is used for locating the oil feeder. Because bearing images are rotational symmetric, also they have perspective distortion, the phase correlation method in frequency domain usually cannot find reasonable rotation angle. This paper presents a new method based on edge images' correlations, at first original images' Canny edges are got after polar coordinate transform, then Hamming distance is used to calculate spatial correlation between bearing images, at last reasonable rotation angles are got when Hamming distance get the minimum value. For this kind of rotational symmetric images with rich edges, experiments show that the proposed method can efficiently solve this problem with much low computation cost.