Research On Catenary Geometry Measurement Technology

The contact wireis the important part of thecontact networks and contact with the pantograph slide plate. Keeping contact force between the pantograph slide plate and the contact wire, so as to keep their uninterruptedelectrical contact. The contact wire is located in orbit above with the appropriate location, which is the key to ensure the normal transmission of OCS and the pantograph slide plateglide smoothly. Normally, we use some parameters to represent position of the contact wire in the space, such as the height of contact wire.stagger and so on, these parameters are collectively known asgeometry parameters of the contact wire.If the geometry parameters of contact wire is not normal, the safety running of the railway will be threatened, so, we must pay attention to the monitoring of the geometric parameters of the contact wire.This paper is based on the principle of binocular stereo vision, combining with the characteristics of the linear scan camera and the pinhole imaging model, proposing the basic physical model of measuring device, the optical axis intersection model. Combining with the physical model, deducing the calculation formula of the contact wire’s geometry parameters and proving the calculation formula. Then, based on the design scheme of measuring device, completing the experimental platform.Using the experimental device to measure the contact wire many times so as to obtain many images of the contact wire.In order to obtain target information from each image, we use the edge detection algorithm to analysis the image with Image processing software. According to thecalibration algorithm of camera, we calculate calibration polynomial coefficients in the formula by using lstOpt mathematical software. Then, measuring the contact wire many times, we can get the coordinate information of the contact wire in the scene with complete calibration algorithm of camera. Comparing the measurement results with the actual measured results and analysing of the error, so that we finish thecalibration of camera.Finally, we can get the coordinate information of the contact wire in the scene with the accomplished measuring device so that we can calculate the contact wire’sgeometric parameters. Then, comparing the measurement results with the actual measured results so as to analysis the measurement error and the reason of error in depth.Based on the pervious analysis of error, proposing the optimizing scheme for the measuring device.