以無線感測網路為基礎之動態監測網建立及解算

On Establishment and Data Process of WSN-Based Real-Time Monitoring Network

蘇煒哲(Wei-Jer Su)

指導教授 ： 韓仁毓

國立臺灣大學/工學院/土木工程學研究所/碩士(2010年)

https://doi.org/10.6342/NTU.2010.01629

摘要

無線感測網路(Wireless Sensor Network, WSN)因為其強大的網絡傳輸效能，近年來廣泛應用於各種工程及生活領域，由於該項技術具有高頻且連續的取樣能力，因此特別適用於以動態監測為目的之觀測任務。
本研究以WSN技術做為平台，並配合虛擬觀測平差技巧的引入，發展出適合WSN網形之動態解算程序，另外也使用序列式平差改進傳統網形解算程序，以進行高頻網形解算；而在即時監測數據處理方面，首先透過靈敏度分析方法決定監測網之變形可偵測性，並使用外部衛星定位觀測將區域解算成果連結至全域坐標系統，獲得監測網於長時間觀測下之絕對變化，最後將節點歷時位移資訊透過快速傅立葉轉換以獲取結構物之頻譜資訊和週期變化，並建構成為一套適合WSN動態定位與監測之完整資料處理和分析流程。
而透過數值實驗成果顯示，由本研究所建議之解算程序除可在無固定基準的動態條件下正確獲得解算成果外，並有效抑制因訊號脫落所而造成之解算誤差。不僅在測量網形的計算上可適應網形的動態變動，更能降低高頻解算的運算時間成本，對於提升WSN在監測實務工作上的可靠度與效率均具有顯著幫助，未來在結構物系統識別等相關技術配合之下，將能夠應用於結構物健康檢測與分析等任務，以具體提升結構物安全診斷與潛在災害預警等工作之效能。

關鍵字

虛擬觀測平差 ； 序列式平差 ； 靈敏度分析 ； 坐標轉換 ； 變形分析 ； 無線感測網路 ； 結構物健康監測

並列摘要

The Wireless Sensor Network (WSN) technique has been widely applied in engineering applications as well as in our daily life for its powerful networking capability. This technique is particularly feasible for a dynamic monitoring task since it provides continuous observables at a high sampling rate. In this study, a WSN-based wireless positioning network is established, and a rigorous approach for processing its dynamic observations has been developed by utilizing the unified least-squares technique. A sensitivity analysis is also carried out to evaluate the quality of the monitoring network in detecting deformations. Then, the local positioning solutions are transformed into a global reference frame by employing external GPS measurements, and the Fast Fourier Transform (FFT) technique is performed to obtain the spectral information of the measured target. Finally, all the above procedures are integrated and a completed flow for WSN data processing and analyzing is thus established. Based on numerical test results, the proposed approach has been proven for its capability in producing a quality solution for a WSN-based monitoring network. Consequently, when it is incorporated with the Structural Health Monitoring (SHM) technique, the reliability and efficiency for a structure safety evaluation and hazard mitigation task can be substantially improved.

並列關鍵字

Unified Least-Squares Adjustment ； Sequential Adjustment ； Sensitivity Analysis ； Frame Transformation ； Deformation Analysis ； Wireless Sensor Network ； Structure Heath Monitoring

參考文獻

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