English  |  正體中文  |  简体中文  |  Items with full text/Total items : 28611/40652
Visitors : 763435      Online Users : 70
RC Version 4.0 © Powered By DSPACE, MIT. Enhanced by NTU Library IR team.
Scope Adv. Search

Please use this identifier to cite or link to this item: http://ntour.ntou.edu.tw:8080/ir/handle/987654321/5984

Title: 船舶運動模擬系統
Ship Motion Simulator
Authors: David Lin
Contributors: NTOU:Department of Computer Science and Engineering
Keywords: 物理引擎;船舶運動;虛擬實境
Physics engine;Ship motion;Virtual reality
Date: 2005
Issue Date: 2011-06-22T08:42:11Z
Abstract: 摘要   物理模擬引擎為遊戲以及虛擬實境系統中不可或缺的一部份,其主要是用於計算物體經由外力影響所造成的運動以及形變。本論文中將船舶視為一漂浮於海面之上的剛體,且提出ㄧ適用於船舶航行模擬之物理模形。船舶的運動含六個自由度運動:起伏、橫搖、縱搖、縱移、橫移、平擺,這些運動可以分成兩類,其一為與波浪激盪力有關的運動,另一為與船舶推進力、舵力、海流、風力等有關的運動,要計算運動量的大小之前,首先要計算作用於船舶之上的作用力,然後基於牛頓運動定律可以計算出加速度再以此求出速度,最後運動量可以經由速度與時間間隔相乘來獲得,且可依此更新船舶方位與位置。 在相同的環境狀況下,不同型態的船舶之運動並不ㄧ致,為了考慮這些現象我們將船舶分為三類:窄船、平板船、細長船。船舶主要是藉由船長、船寬、吃水以及波長之間的比值來分類,為了呈現船舶各自的特性,我們使用不同的參數組合來表示船舶受力作用時的反應,並以此提出ㄧ簡易的機制用於操縱及模擬船舶運動。
Abstract Physics engines are vital components for games and virtual reality systems. They are used to calculate motions and deformation of objects due to external or internal forces. In this article, simple physical models are presented for simulating ship motions. In our procedures, a ship is treated as a rigid body floating on sea surface. Its motions compose of six degree of freedom: pitch, heave, roll, surge, sway, and yaw. These motions are classified into two categories. The first three movements are assumed to be induced by sea waves, and the last three ones are influenced by ship propellers, rudders, currents, and winds. To compute the magnitudes of motions, the forces acting on the ship are estimated first. Then, based on Newton’s laws, accelerations are computed and used to modify velocities. Finally, the motion magnitudes are obtained by multiplying the velocities with the time step. In turn, the orientation and position of ship are updated. Under the same environmental condition, motions of different ships are different, depending on their shapes. To accommodate the effects of ship shapes, we divide ships into three types: Thin Ship, Flat Ship, and Slender Ship. A ship is classified according to the ratios between its length, breadth, and module depth. To model the character of the ship, several coefficients are associated with it to express its reactions when encountered forces. Therefore a simple mechanism for handling and modeling ships is established.
URI: http://ethesys.lib.ntou.edu.tw/cdrfb3/record/#G0M93570028
Appears in Collections:

Files in This Item:

There are no files associated with this item.

All items in NTOUR are protected by copyright, with all rights reserved.


著作權政策宣告: 本網站之內容為國立臺灣海洋大學所收錄之機構典藏,無償提供學術研究與公眾教育等公益性使用,請合理使用本網站之內容,以尊重著作權人之權益。
網站維護: 海大圖資處 圖書系統組
DSpace Software Copyright © 2002-2004  MIT &  Hewlett-Packard  /   Enhanced by   NTU Library IR team Copyright ©   - Feedback