Image Processing Principles Of Applied Research In The Measurement Of Geometric Parameters Of The Power Contact Wire

The electric train attains energy from contact wire by pantograph in the power supply system of the electric railway. It was frayed because of distortion, vibration, different height to rail and so on. The geometry parameters of electric contact wire must to be measured real-time, effectively and economically in order to operate in security and reduce cost. In this paper, the domestic and overseas detecting methods of contact wire were analyzed and compared. After a deep study on these methods, a non-contact detecting method was draw based on image process. The binocular stereovision technique was applied in geometry parameter measurement. Image signal of electric contact wire was obtained, and then, the coordinates of abrasion edge points were numerated by edge detection. Thus the result could be obtained.Expressions of the geometry parameter of electric contact wire were gained according as the theory of the binocular stereovision technique based on image process in this paper. The relations among measurement precision, resolving capability, performance indexes of image sensors, optical system parameters, and structure parameters of the measurement system were analyzed in detail by using error theory. The structure parameters were optimized and the best precision in theory was carried out with computer simulation. An approach was presented to detected image edge at the level of sub pixel using LOG function and linear least square fitting when the image process technique was researched profoundly. And then the image process program was preliminary carried out in the Visual C++.It is showed that the scheme is correct and feasible by plenty of simulation experiments. This provides a good base for marketable and producible of the geometry parameter measurement system of electric contact wire.