第六章 結論與未來展望
6.2 未來展望
由有限元素分析模擬偵測損傷例中可知，欲以結構模態曲率理論偵測其損傷 需要擁有足夠之通道數與取得精確之模態振形，基於這些原因，吾人提出些許之 建議可供未來研究之參考：
1. 由 6.1 節中結論所提到，若能自動化過篩選系統特徵根，則可提升識別 模態振形之速率；此外如能先將含雜訊之輸出響應配合系統識別前處理 等相關濾訊過程，則可增加識別模態振形之精確度。
2. 本文考慮之損傷偵測狀況為含雜訊輸出響應下識別結構之模態參數而並 未考慮有輸入外力之情況，根據系統識別相關文獻[19-28]，理論上以 ARX 模型同樣也可識別出結構之模態參數後搭配模態曲率理論進行損 傷偵測，此部分本研究中未嘗試過相關之模擬。
3. 本文所使用數值處理之方式中僅於立方雲線可有增進偵測損傷之成效，
或許仍存在其餘更為良好之數值處理方法。
4. 可嘗試模態曲率法對不同形式結構之適用性，本研究中僅針對懸臂樑結 構探討其損傷偵測之內容，理論上對於不同之結構形式可假設相應之邊 界條件與初始狀況，此部分則未進行相關之模擬。
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5. 本文以模態振形透過中央差分法計算模態曲率，此外模態曲率也與結構 之撓曲應變有著直接的關係，可藉由應變之量測以得到模態曲率；Chance 曾在相關研究中表示，若改以量測應變間接得到模態曲率，對於模態曲 率而言有較好之精確度[31]。
6. 損傷偵測相關研究之終極目標是為了對結構使用壽命作出正確的評斷，
而本文中所介紹之損傷偵測內容可達到對受損位置之定位，對於結構受 損程度與估算其剩餘使用壽命並未作深入之研究，但於參考資料[8]中有 提出以假設結構材料性能之劣化程度為時間之線性函數之前提下，以損 傷因子之假設估算結構剩餘使用壽命，若可搭配相關理論並取得實驗數 據則可接續探討此部分。
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