ANALYSIS OF RAIL DEFECTS SIGNALS BY THE MATLAB WAVELET TOOLBOX PROGRAMME

Abstract

Rail networks across the world are getting busier with trains travelling at higher speeds and carrying more passengers and heavier axle loads than ever before. The combination of these factors has put considerable pressure on the existing infrastructure, leading to increased demands in inspection and maintenance of rail assets [1]. Nowadays, rails are systematically inspected for internal and surface defects using various nondestructive evaluation (NDE) techniques. The most common of which are ultrasonic and magnetic flux leakage (MFL) methods. The article is focused on the analysis of defectoscopic signals received using the magnetic wagon-defectoscope of Lviv Railway (MFL method) by the continuous wavelet transform (CWT). The most important question in all methods NDE - is selection of information about defects from defectoscopic signals received during the checking railway (defectogram). At present, wagon-defectoscope operator’s experience is essential for making the correct decision about technical condition of rails. To improve the operator’s work efficiency, which is mainly based on expert visual assessments, it is necessary to automate the analysis9 of recorded signals. That is why we turned to the powerful tool of digital signal processing such as wavelet transform (WT). The main WT applications - analysis and processing signals, non-stationary in time (such as defectoscopic signals) when the analysis should include not only the signal frequency characteristics, but also information about some local coordinates, which reveal themselves in one or other frequency components. WT divides into continuous (CWT) and discrete (DWT). DWT focuses on speed (by sampling values of scale (frequency) and time (samples)) and the possibility of a complete reconstruction of the signal after analysis (by orthogonal wavelet functions), which led to its use, mostly for denoising and compression of signals. As for CWT, it requires only one wavelet function - mother, whose creation is not problematical (unlike DWT) and allows to identify those signals that are similar to the mother wavelet.

Authors and Affiliations

Vitaliy Nichoha, Liubomyr Vashchyshyn, O. Saldan

Keywords

Related Articles

The system maopcs for the multivariate analysis and optimization of linear parametric circuits at the enviroment of matlab

This paper considers the software realization the system of functions MAOPCs (Multivariate Analysis and Optimization of the Parametric Circuits) for multivariate analysis and optimization of linear parametric circuits ba...

RESEARCH OF WIDTH OF WORKING SECTOR OF DIRECT DIGITAL CORRELATIVE-INTERFEROMETRIC DIRECTION FINDER WITH RECONSTRUCTION OF SPATIAL ANALYTICAL SIGNAL

It was conducted the research of the width of the working sector and the exactness of direct digital correlative-interferometric direction finder that uses reconstruction of spatial analytical signal. It is shown that th...

MULTICHANNEL DATA TRANSMISSION SYSTEM IN THE SPLINE BASES

The article deals with multichannel digital data transmission system in which the digital signal is transmitted through the manipulation of the harmonic function which performs subcarrier function with different frequenc...

QUADRATURE DETECTOR SYMBOLIC MODEL

Quadrature detectors (QD) are widely used in a radioelectronic devices as alternative to the synchronous detectors. There are many applications where there is necessary to measure the amplitude of input signal with speci...

DYNAMICS OF PULSE SIGNAL FORMING FROM DISTAL ZONES OF RADIAL ARTERIES

In last time new methods and hardware-software system, which combine eastern medicine traditions and western technologies are commonly used in diagnostic practice. Pulse diagnostics is one of the ancient methods for dise...

Download PDF file
  • EP ID EP459701
  • DOI -
  • Views 145
  • Downloads 0

How To Cite

Vitaliy Nichoha, Liubomyr Vashchyshyn, O. Saldan (2014). ANALYSIS OF RAIL DEFECTS SIGNALS BY THE MATLAB WAVELET TOOLBOX PROGRAMME. Вісник Національного університету "Львівська політехніка", серія "Радіоелектроніка та телекомунікації", 796(2014), 8-13. https://www.europub.co.uk/articles/-A-459701