A Synchronized Wireless Sensor Network for Experimental Modal Analysis in Structural Health Monitoring |
| |
Authors: | Maurizio Bocca Lasse M. Eriksson Aamir Mahmood Riku Jäntti Jyrki Kullaa |
| |
Affiliation: | 1. Department of Automation and Systems Technology, Aalto University School of Electrical Engineering, Helsinki, Finland;2. Department of Communications and Networking, Aalto University School of Electrical Engineering, Helsinki, Finland;3. Department of Applied Mechanics, Aalto University School of Engineering, Helsinki, Finland |
| |
Abstract: | Abstract: Structural health monitoring aims to provide an accurate diagnosis of the condition of civil infrastructures during their life span using data acquired by sensors. Wireless sensor networks represent a suitable monitoring technology to collect reliable information about the structure's condition, replacing visual inspections, and reducing installation and maintenance time and costs. This article introduces a time synchronized and configurable wireless sensor network for structural health monitoring enabling a highly accurate identification of the modal properties of the monitored structure. The wireless sensor nodes forming the network are equipped with a 3‐axis digital accelerometer and a temperature and humidity sensor. The implemented Medium Access Control layer time synchronization protocol (μ‐Sync) ensures a highly accurate synchronicity among the samples collected by the nodes, the absolute error being constantly below 10 μs, also when high sampling frequency (up to 1 kHz) and extended sampling periods (up to 10 minutes) are applied. The experimental results obtained on a wooden model bridge, compared with those derived from acceleration signals acquired by high‐quality wired sensors, show that the so synchronized wireless sensor nodes allow a precise identification of the natural frequencies of vibration of the monitored structure (1% maximum relative difference). |
| |
Keywords: | |
|
|