A Method to Extract Rail Flatness Profile and Analysis of Different Noise Sources

This article addresses the problem of the rail flatness assessment that occurs at its final production stage. Flatness control must be measured during the total length of each rail to avoid problems during this rail usage. Only the flat rails can be used in high-performance environments such as high-speed trains. Rails quality assessment must be done to avoid highway security problems or any other type of circumstances that may prevent the normal operation of the systems where these rails will be installed. The rail that does not meet the minimum flatness requirement for the high-performance usage, can be used in standard railways, but if the flatness imperfections are greater than certain tolerances, it must go through a process of restraightening or been discarded. To obtain the rail points where flatness will be measured, we propose a method based on a set of cameras distributed in a range along a section of the rail. The goal is to reduce the impact of the rail vibrations, and then, obtain a synthetic shape that calculates the original rail shape. This shape can be used to measure rail flatness using any other process. The obtained results indicate that this method is robust and accurate.