Research On Vibration Measurement System For Bridges Based On Wireless Sensor Networks

With the development of national economy, brigde plays more important part in people’s livelihood. The security issue of bridge has been paid enough attention after some major accidents. The vibration measurement is an effective detection means, which can discover the security status of the bridge structure. The main vibration measurement is using wire connection mode, which has more disadvantages. The wireless sensor network (WSN) is just right for bridge vibration measurement because of more advantages.According to the problems living in bridge vibration measurement, a measurement scheme is proposed based on wireless sensor network, and the developed the corresponding portable system with the real application background. In this aticle, the wireless communication mode is proposed based on ZigBee, and the star topology is used. Then the shemes is put such as system composition, expand application, and so on. The hardware platform designed and the main components selection are carried out following on. While designing the software of the system, an energy-saving technology for wireless sensor nodes is developed, and the corresponding mathematical model is established befor simulating. Then a type of IIR digital lowpass filters based on butterworth relating with anti-aliasing filter is developed to get better filtering results, and the flitering effect was simulated and analyzed. Thereafter, the system software for wireless sensor node, base station, and terminal data display interface is designed.Some experiments are carried out to verify the performance of the explored system, including the operational reliability of vibration signals acquisition and wireless transmition, filtering performance of the digital lowpass filter, calibration for wireless sensor nodes, and operational reliability while all parts of the system are operating together. The results show that the system is with reliable working, it can get good filtering effect, and all parts of the system have good synchronism while operating. And the main parameters of working performance for wireless sensor nodes can also meet the standard technique of JJG233-2008.