In-Situ Validation of a Wireless Data Acquisition System by Monitoring a Pedestrian Bridge

When compared to wired sensor technology, wireless sensor technology often suffers long data collection delay, big noise floor and data loss. Addressing these challenges, a wireless data acquisition system was designed and implemented by the authors. It can provide a performance comparable to the one of a wired data acquisition system. In this paper, the system is validated by its application in the monitoring of a timber pedestrian bridge in Italy. The system features flexible sensor interfaces, high power efficiency, low noise data acquisition, real-time and lossless wireless data transmission, and a convenient graphical user interface. Two field experiments were conducted. In the first experiment, the wireless data acquisition unit was designed to use an unreliable communication mode, resulting in an underestimated data loss problem. In the second experiment, the system is improved. The ACK-RETRIES reliable communication mode and a data packet sequence number checking mechanism are adopted, so that the data loss was avoided. For a comparison, a wired portable data acquisition system VSS-3000 was also used to acquire data from one accelerometer. The results show that the wireless data acquisition system is able to acquire high quality data from low noise sensors in real time without data loss. Compared to the VSS-3000, the data acquired by the wireless sensor platform have a comparable and even better quality.