Development Of Wireless Sensor Network And Application Technology For Structural Health Monitoring

SHM technology is based on the requirement of all kind information of structure and successful transmission through the network. At present, all data collecting methods realized in SHM are mainly by wired sensors. But the network constructed by the wired sensors needs amount of wires, the spending on maintenance is also expensive. Smart sensors with high computational and wireless communication capability, without the need of deploying wires, reduce the installation and maintenance costs to a great extent. Smart structural health monitoring technology based on wireless sensor network providing a new method for structural status information acquisition, safe operation of structure and system instrumentation.This thesis addresses the research on application of smart sensors. Including configure and installation of the operation system to support the smart sensors'work, development of the component in software level. This object has been listed as national natural science fund sponsor item (50678099).First, the smart sensor Micaz was researched. The work includes compiling program for acceleration collection and being compared with wired sensors in the experiment of testing vibration character of cantilever beam. The results showing that the wireless network consisted by many smart sensors can finish data collection. By analyzing the signals, the frequency of the structure can be identified.Second, Smart sensor Imote2 with more advanced capability was researched. In the case of simulating a band-limited white noise signal excitement, Imote2 and wired sensors were installed on the structure at the same time. By comparing the output with the Siglab spectrum analysis system, the sensing capability of Imote2 was verified.Finally, a distributed data acquisition system was adopted, and time synchronization chemical was discussed. The smart sensors were conceptually divided into hierarchical levels and several groups. Sensors in different levels execute pre-designed tasks, there're cross existed in two neighboring groups.To verify the feasibility of the distributed system, ten Imote2s were installed on a concrete-filled steel tube arch bridge, three sensor communities was constructed to measure acceleration. The result shows the effective of the data collection system, each level nodes can perform successfully.In conclusion, the realization of distributed data acquisition system paved the way for SHM on Imote2s. Distributed computing strategy is considered suitable for implemented on network of densely deployed smart sensor.