Design and implementation of non-contact detection system for catenary based on double linear array cameras

Abstract

The detection of catenary geometric parameters is a very important problem in railway infrastructure measurement. In this paper, a high resolution linear array CCD is used as the photosensitive element, and FPGA is used as the main controller to design the data acquisition system of linear array camera, and a non-contact detection system of catenary geometry parameters based on double linear array cameras is implemented. According to the intensity of linear array CCD output signal, and the adaptive adjustment algorithm of exposure intensity is achieved, so the optical integration time is changed in real time. In order to improve the bandwidth limitation of data transmission, the calibration algorithm of pixel position in the system is completed by FPGA, which improved the response speed of the system. The experimental results show that the scan frequency of linear array camera can reach 6MHz, the measurement error is controlled at mm level, and it has good accuracy and stability.