Impact of time synchronization error on the mode-shape calculation in wireless sensor networks for structural health monitoring

Abstract

For structural health monitoring (SHM), mode shape calculation is an important task that needs to be performed accurately and reliably. The use of wireless sensor networks (WSNs) for SHM is a very effective and a promising solution. However, WSNs experience synchronization errors among the sensor nodes, which can affect the accuracy of the mode shape calculation. In this paper, we study the impact of time synchronization error (TSE) on the mode shape calculation in a semi-local manner using frequency domain decomposition (FDD) implemented in a semi-local manner. In order to decrease the size of the transmitted data by the sensor nodes and reduce the processing load and needed storage capacity on the central unit, we adopt a semi-local processing approach where each node partially processes the measured data. Then, sensor nodes send the partially-processed data to a central unit for further processing and mode shape calculation. Numerical results prove that the time synchronization error has a significant impact on the accuracy of the mode shape calculation. Furthermore, results show that semi-local processing is more sensitive to TSE compared with centralized processing. 2016 IEEE.