A Kalman Filter Based Acoustic Emission Signal Detection and Denoising Method for Rail Cracks

Abstract

The invention discloses a rail crack acoustic emission signal detection and denoising method based on Kalman filtering, the steps are as follows: step 1: establish a linear time series AR model of wheel-rail contact noise; Basic equation of Kalman filter for rail contact noise; Step 3: Kalman recursive filter to estimate wheel-rail contact noise; Step 4: Suppression of wheel-rail contact noise. Compared with the prior art, the present invention has the following advantages: 1) on the basis of the noise acoustic emission signal that can be directly measured, an AR model is established for the known noise signal part to carry out Kalman filtering to obtain the estimation of the noise signal, The occurrence of the rail crack signal can be detected without knowing the prior knowledge of the rail crack signal; 2) the denoising method proposed by the present invention can still achieve noise suppression under the high-speed situation where the rail crack signal is completely submerged in the noise signal, The purpose of detecting the occurrence of rail cracks.

Description

technical field [0001] The invention relates to a denoising method for flaw detection of high-speed rail rail acoustic emission technology, in particular to a method for detecting and denoising rail crack acoustic emission signals based on Kalman filtering. Background technique [0002] At present, my country's high-speed railway is developing vigorously, but due to the long-term extrusion deformation and fatigue wear of the rail during driving, cracks, breakage or other forms of damage will occur on the surface and interior of the rail. The rail fracture caused by the expansion of rail cracks is The main reason for train derailment accidents, and the increase in the speed of high-speed trains greatly increases the probability of cracks. The existing large-scale flaw detection vehicles and hand-push flaw detectors occupy the road for a long time and have low operating efficiency, so they are not suitable for rail flaw detection of high-speed railways. Acoustic emission techn...

AI Technical Summary

Problems solved by technology

However, due to its sensitivity, acoustic emission technology is easily disturbed by external noise. Effective crack signal detection is accompanied by noise signals.

When the train speed is high, the generated noise signal will completely submerge the rail crack signal, resulting in the indistinguishable rail crack signal, which is the main problem hindering the application of acoustic emission technology flaw detection at high speed

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