The Application Of Binocular Stereo Vision Based On The Camera Rotation In The Ice Monitoring For Contact Wires

As the railway stretches to the cold and remote areas in our country, and the frequency of the bad weather, the effects of ice coating on contact wires is growing. The ice on contact wires not only affects the normal operation of the train, but also even leads to serious accidents, the main hazards are:The ice shell on contact wires makes the pantograph cannot take electricity; The ice on contact wires is easy to become icicle and scratches pantograph, increasing the wear of pantograph; After ice coating, due to the linear density increasing, the wave speed and the quality of absorption current reduced; Wires gallop because of the wind load and ice weight beyond the design value; Electric arc is produced between the pantograph and wires, and the instantaneous high temperature burns the pantograph and wires.In view of the lack of research on ice coating on contact wires, and the deficiency of the current methods, this paper put forwards a kind of image monitoring method based on binocular stereo vision for ice coating online monitoring on contact wires. First, study the calibration method of external parameters for the camera with pan-tilt-device rotating to any position, achieve the goal of binocular stereo vision, solve the problems of traditional technique that the intrinsic parameters are inconsistent, need to re-calibration after camera moving, less monitoring range, need to set up two cameras. Second, in terms of extracting feature points, this article adopts the algorithm of wavelet absolute maximum value combined with edge growth under multiple threshold, and mathematical morphology to extract profile of contact wires which is single pixel and continuous. This method is adaptive and has good extraction effect under complex background. Third, in terms of feature matching, the feature points can be divided into two types. By using epipolar constraint and the relationship between the feature points, can improve the matching accuracy and reduce the time complexity.The improved method of binocular stereo vision can rebuild the3d view of contact wires and calculate the ice thickness and the length of icicle through a certain algorithm. Application of this algorithm to analysis multiple sets of images, the practical results show that the method can accurately calculate the ice thickness and the length of icicle. The precision is high and the measurement error less than6%. It can meet the needs of monitoring, expand the scope of monitoring and provide a new method for online remote measurement of ice coating on contact wires.