Применение методов преобразования Фурье и вейвлет-преобразования для вибродиагностики технического состояния тоннельных эскалаторов

Abstract

To consider the possibility of improving the detection of early signs of escalator defects. To develop and improve methods for testing and functional diagnostics of escalators. To propose methods for digital signal processing. To develop an approach for correcting interpretation of signal processing results. The methods of vibration diagnostics and digital signal processing were used: including Fourier and wavelet transform. A comparison of Fourier and wavelet transform methods is presented. The possibility of their successful application for signal processing is shown. It was shown that the parameters of vibration diagnostic techniques and the methods of digital signal processing – Fourier transform and wavelet transform-require improvement. The reliability of calculation results can be increased by considering highly variable operational conditions of tunnel escalators. The need for additional examination of the technical condition of tunnel escalators is revealed. Fourier transform and wavelet analysis reveal changes in the nature of oscillations along the leads (an increase or a decrease in the energy level in the leads in phase and diametrically change places depending on the operation mode of the machine). This circumstance indicates the presence of gaps that are «selected» in a characteristic manner every time the direction of movement is changed. When there are any inhomogeneities in the material, wavelet transform analysis may provide the necessary information to determine the design defects, along with their location and possible defect type. The above considerations make the proposed methods of Fourier and wavelet transform of signals to be practically feasible.