比較SRIM、SSI及RLS於結構系統識別中最佳化模式參數之決定

Determine the Optimal Model Parameters Using SRIM、SSI and RLS Methods on Structural System Identification

簡劭純(Shao-Chun Chien)

指導教授 ： 羅俊雄

國立臺灣大學/工學院/土木工程學研究所/碩士(2008年)

https://doi.org/10.6342/NTU.2008.00054

摘要

系統識別乃是從結構量測而得之輸出入資料中，利用數學模型鑑定結構系統特性及推算結構力學模型。本文之目的在於將各種系統識別方法中所需求得之未知參數作有系統性的規劃，使不同的使用者都能有一套詳細的流程及定義可以參考。在此我們介紹三種識別方法，分別是信息矩陣之系統實現理論 (System Realization using Information Matrix ，SRIM) 、隨機次空間運算法(Stochastic Subspace Identification method ，SSI)以及使用ARX模型之遞迴最小平方法(Recursive Least Squares ，RLS)，分別根據各方法中的參數作一完整的選取準則，同時以模態物理參數(自然頻率、阻尼比及模態振型)作為各方法間比較的依據。

為了驗證本文提出識別步驟之可行性及有效性，首先我們選擇一模擬之三層樓結構來作為測試及說明。同時也將此技術應用至各種振動台之實驗以及真實結構物-中央百世大樓均能有良好之識別結果。

關鍵字

系統識別 ； 信息矩陣之系統實現理論 ； 隨機次空間運算法 ； 遞迴最小平方法 ； 模態物理參數

並列摘要

System identification is a procedure to determine the system characteristics of structure and the parameters of mathematical model for structural mechanics from measured input and output data.. The purpose of this paper is to identify ways in various systems of unknown parameters required to seek a systematic planning,so that different users can have a detailed process and the definition of reference.
Here, we introduced three identification methods, respectively are System Realization using Information Matrix (SRIM)、Stochastic Subspace Identification method(SSI) and Recursive Least Squares with ARX model (RLS), Were in accordance with the parameters in the way for a complete selection criteria, to modal physical parameters (natural frequency, damping ratio and the mode shape) as the basis for comparison between the methods.

In order to verify the steps proposed in this paper to identify the feasibility and effectiveness, first of all, we choose a simulated three floors of the structure as a test and description. Application of this technology but also to all kinds of shaking table and the real test of the structure - the central Bai-shin building can have good results of the identification.

並列關鍵字

System identification ； System Realization using Information Matrix (SRIM) ； Stochastic Subspace Identification method(SSI) ； Recursive Least Squares with ARX model (RLS) ； modal physical parameters

參考文獻

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