Vibration Analysis of an Axially Moving Plate Based on Sound Time-Frequency Analysis

Abstract

In some types of non-contact measuring systems, vibrating motion has negative effects on accuracy. Therefore, there is a need to analyze and monitor the motion state of a moving part using a low-cost scheme. This study focused on the vibration analysis and monitoring of a poly-crystalline silicon solar wafer carried by a pair of parallel moving strings, separated by a distance. Based on the sound data series picked up by a low-cost microphone and using a time-frequency analysis method, namely, the Hilbert-Huang transform (HHT) method, the low frequency features of the moving wafer could be determined quantitatively. The results showed that the motion of the moving wafer was sensitive to speed and string tension. By comparison, the average marginal spectrum should be treated as the basis for quantitative vibration monitoring, especially for a system with a strict requirement in terms of motion smoothness.