繫纜式水下滑翔機之動力學研究

On the Dynamics of a Cable-connected Underwater Glider

洪柏棟(Bo-Dong Hong)

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(2022年)

https://doi.org/10.6342/NTU202201115

摘要

水下滑翔機是一種利用改變自身浮力大小在水中移動的自主式水下載具，通常會搭載浮力引擎以及移動質量塊，浮力引擎為水下滑翔機的動力單元，移動質量塊可以在水下滑翔機運動時改變其姿態。本研究將水下滑翔機連接纜線，針對繫纜式水下滑翔機於水中的運動以及浮出水面後與波浪之間的交互關係推導運動方程式。本研究利用克希霍夫方程式推導基礎的水下滑翔機運動方程式，離散化的纜線運動方程式則由質量集總法推導而得；為了瞭解滑翔機於水面上與波浪的交互作用，本研究估算滑翔機受到的波浪激發力，並且利用比例濕參數修正運動方程式。於實作上，本研究設計、製造了繫纜式水下滑翔機試驗機以進行水槽實驗，將實驗結果與運動方程式數值分析進行比較，結果顯示本研究所推導的運動方程式具有一定的可參考性。最後本研究調整數值分析中的各個參數（纜線連接位置、纜線長度限制、波浪規格與滑翔機浮心與重心間距離）以了解繫纜式水下滑翔機在浮出水面的過程中的動態響應、並提出滑翔機重浮心間距離與波高之關係表，作為繫纜式水下滑翔機設計時的參考。本研究所提出的繫纜式水下滑翔機可作為通訊浮標，為水下載具的通訊提供一個更具有彈性的選擇。

關鍵字

水下滑翔機動力學 ； 離散化纜線模型 ； 浮體動力學 ； 波浪激發力

並列摘要

Underwater glider is an autonomous underwater vehicle that moves in the water by altering buoyancy. An underwater glider is usually equipped with a buoyancy engine and a moving mass mechanism. The buoyancy engine can change the buoyancy of the underwater glider, and the moving mechanism can adjust the posture of the underwater glider. The study connects the underwater glider with a cable and discusses the motion of the cable-connected underwater glider in the water and on the water surface. A six-degree-of-freedom motion equation of the underwater glider is derived based on Kirchhoff's equation, added with fluid forces effects. The cable model is derived using lumped mass method. The coupled motion equation of a glider in ascending is derived, and wave excitation force acting the glider body is considered when the glider is floating on the surface. A cable-connected underwater glider testbed is designed and manufactured to examine the dynamic behaviors of the glider. Water tank experiments are conducted using the glider released from a cable reel underwater and ascending to the water surface. The experiment results show that the motion of the cable-connected underwater glider could be predicted well by numerical simulations using the dynamic model derived in this work. Finally, the dynamic model is used to examine design parameters such as the cable connection position, the tension in the cable, and the distance between the center of gravity and the center of buoyancy. The cable-connected glider proposed in the study can be applied in underwater vehicle communication as a type of communication buoy and provides a more flexible choice for underwater vehicle communication.

並列關鍵字

underwater glider motion equation ； discretized cable model ； floating body dynamics ； wave excitation force

參考文獻

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