潛艦系統鑑定之最佳輸入設計

Optimal Input Design for Submarine System Identification

周士閔(Shih-Min Chou)

指導教授 ： 郭振華

國立臺灣大學/工學院/工程科學及海洋工程學研究所/碩士(2004年)

https://doi.org/10.6342/NTU.2004.00594

摘要

潛艦為因應不同深度航行，避敵或攻擊之需要，必須具備高度的操控性能，而其主要基礎則在於建立掌握潛艦操控運動數學模式及其相關流體動力係數之能力，所以在潛艦運動數學模式中，流體動力係數的正確性對於潛艦的控制操控性能影響甚鉅。本篇論文以非線性估測器理論為基礎提出對潛艦的流體動力係數作即時系統識別的研究，實際結合待估測的未知參數與雜訊的關係，降低系統識別的不確定性。此外，提出最佳輸入設計，在即時系統識別過程中，控制潛艦運動的路徑有利於提昇識別參數的準確性。最後利用模擬比較最佳輸入與隨機白色二值輸入(PRBS)證明本文所提出潛艦系統鑑定之最佳輸入設計能夠準確識別潛艦的流體動力係數。

關鍵字

系統鑑定 ； 最佳輸入 ； 水下載具

並列摘要

The accuracy of hydrodynamic coefficients in a submarine vehicle’s dynamic model strongly affects the dynamic performance of its control system. This thesis presents a mutual-information-based observability metric for the on-line dynamic parameter identification of a submarine vehicle. The method provides practical means of estimation unknown parameters and plant noises using a nonlinear observer, as well as estimating the uncertainty associated with the parameters. A metric for selecting optimal input signals for parameter identification is also proposed. The trajectory of the submarine is controlled so that the identification procedure favors parameters that have the greatest uncertainty at any given time. Optimal rudder/elevator deflections for identifying the hydrodynamic coefficients of the submarine are demonstrated using computer simulations. The estimated values are compared with the Pseudo-Random-Binary-Sequence input signals that are commonly used in system identification. This algorithm for selecting optimal inputs is found to be efficient and robust to noises.

並列關鍵字

Underwater Vehicles ； System identification ； Optimal inputs

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